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University of Georgia
1.
Stibrich, Nathan Joseph.
Focal point extrapolation procedures: extension to the coupled cluster singles, doubles, triples, and perturbative quadruples CCSDT(Q) level of theory.
Degree: MS, Chemistry, 2008, University of Georgia
URL: http://purl.galileo.usg.edu/uga_etd/stibrich_nathan_j_200808_ms 
► The high level of accuracy obtained with present computational chemistry methods is rapidly increasing with faster computing, more efficient codes, and higher levels of theory…
(more)
▼ The high level of accuracy obtained with present computational chemistry methods is rapidly increasing with faster computing, more efficient codes, and higher levels of theory becoming available for general use. Chemical accuracy is within the field’s grasp for most small molecules. However, some investigations warrant even higher accuracy that that. In this work, the recently implemented coupled cluster with singles, doubles, triples, and perturbative quadruples [CCSDT(Q)] level of theory is exploited under the focal point scheme to attain very accurate properties for the HCCO radical and implications for its further utility are discussed.
Advisors/Committee Members: Henry F. Schaefer.
Subjects/Keywords: Ab initio
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APA (6th Edition):
Stibrich, N. J. (2008). Focal point extrapolation procedures: extension to the coupled cluster singles, doubles, triples, and perturbative quadruples CCSDT(Q) level of theory. (Masters Thesis). University of Georgia. Retrieved from http://purl.galileo.usg.edu/uga_etd/stibrich_nathan_j_200808_ms
Chicago Manual of Style (16th Edition):
Stibrich, Nathan Joseph. “Focal point extrapolation procedures: extension to the coupled cluster singles, doubles, triples, and perturbative quadruples CCSDT(Q) level of theory.” 2008. Masters Thesis, University of Georgia. Accessed March 29, 2020.
http://purl.galileo.usg.edu/uga_etd/stibrich_nathan_j_200808_ms.
MLA Handbook (7th Edition):
Stibrich, Nathan Joseph. “Focal point extrapolation procedures: extension to the coupled cluster singles, doubles, triples, and perturbative quadruples CCSDT(Q) level of theory.” 2008. Web. 29 Mar 2020.
Vancouver:
Stibrich NJ. Focal point extrapolation procedures: extension to the coupled cluster singles, doubles, triples, and perturbative quadruples CCSDT(Q) level of theory. [Internet] [Masters thesis]. University of Georgia; 2008. [cited 2020 Mar 29].
Available from: http://purl.galileo.usg.edu/uga_etd/stibrich_nathan_j_200808_ms.
Council of Science Editors:
Stibrich NJ. Focal point extrapolation procedures: extension to the coupled cluster singles, doubles, triples, and perturbative quadruples CCSDT(Q) level of theory. [Masters Thesis]. University of Georgia; 2008. Available from: http://purl.galileo.usg.edu/uga_etd/stibrich_nathan_j_200808_ms
University of Georgia
2.
Bera, Partha Pratim.
Ab initio quantum chemical predictions of structures, energetics and physical properties: from environmentally active molecules to small clusters to dna base pairs.
Degree: PhD, Chemistry, 2007, University of Georgia
URL: http://purl.galileo.usg.edu/uga_etd/bera_partha_p_200705_phd
► Ab initio quantum chemistry (AIQC) methods have been employed in order to investigate small environmentally active triatomic NO2 to large DNA base pairs in this…
(more)
▼ Ab initio quantum chemistry (AIQC) methods have been employed in order to investigate small environmentally active triatomic NO2 to large DNA base pairs in this thesis. The reliability of predicting structures, energetics and physical properties of molecular systems are discussed with an eye on the applicability of density functional theory and highly correlated
methods. Structures and spectroscopic parameters are predicted for several excited electronic states of NO2. An unbiased stochastic method to search for minima on the potential energy surfaces of molecules or clusters is developed and applied to variety of molecules. Biologically
important topic of DNA damage by radiation is also addressed by predicting the gas phase radicals and ions and their molecular properties.
Advisors/Committee Members: Henry F. Schaefer, III.
Subjects/Keywords: ab initio
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APA (6th Edition):
Bera, P. P. (2007). Ab initio quantum chemical predictions of structures, energetics and physical properties: from environmentally active molecules to small clusters to dna base pairs. (Doctoral Dissertation). University of Georgia. Retrieved from http://purl.galileo.usg.edu/uga_etd/bera_partha_p_200705_phd
Chicago Manual of Style (16th Edition):
Bera, Partha Pratim. “Ab initio quantum chemical predictions of structures, energetics and physical properties: from environmentally active molecules to small clusters to dna base pairs.” 2007. Doctoral Dissertation, University of Georgia. Accessed March 29, 2020.
http://purl.galileo.usg.edu/uga_etd/bera_partha_p_200705_phd.
MLA Handbook (7th Edition):
Bera, Partha Pratim. “Ab initio quantum chemical predictions of structures, energetics and physical properties: from environmentally active molecules to small clusters to dna base pairs.” 2007. Web. 29 Mar 2020.
Vancouver:
Bera PP. Ab initio quantum chemical predictions of structures, energetics and physical properties: from environmentally active molecules to small clusters to dna base pairs. [Internet] [Doctoral dissertation]. University of Georgia; 2007. [cited 2020 Mar 29].
Available from: http://purl.galileo.usg.edu/uga_etd/bera_partha_p_200705_phd.
Council of Science Editors:
Bera PP. Ab initio quantum chemical predictions of structures, energetics and physical properties: from environmentally active molecules to small clusters to dna base pairs. [Doctoral Dissertation]. University of Georgia; 2007. Available from: http://purl.galileo.usg.edu/uga_etd/bera_partha_p_200705_phd
University of Georgia
3.
Li, Chenyang.
Applications of coupled cluster theory on infrared spectroscopy and the development of multireference driven similarity renormalization group.
Degree: PhD, Chemistry, 2015, University of Georgia
URL: http://purl.galileo.usg.edu/uga_etd/li_chenyang_201505_phd
► Ab initio quantum chemistry has evolved into a matured field, with tools capable of providing reliable predictions of molecular properties. Notwithstanding the progress, much effort…
(more)
▼ Ab initio quantum chemistry has evolved into a matured field, with tools capable of providing reliable predictions of molecular properties. Notwithstanding the progress, much effort has been investigated in developing methodologies that address very challenging systems. Herein, three studies are presented, including both the application and development of electronic structure theory. First, a study on nonahydridorhenate dianion and molecular potassium and sodium rhenium hydride is reported using coupled cluster theory. Second, the potential energy surface of the methylene internal rotation is carefully investigated for n-propyl radical. The fundamental vibrational frequencies are predicted using second-order vibrational perturbation theory, and energy levels of the methylene torsional motion are also determined. Third, a multireference generalization of the driven similarity renormalization group is introduced. A perturbative analysis of the corresponding equations leads to an efficient and intruder-free multireference perturbation theory.
Advisors/Committee Members: Henry F. Schaefer, III.
Subjects/Keywords: ab initio quantum chemistry
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APA (6th Edition):
Li, C. (2015). Applications of coupled cluster theory on infrared spectroscopy and the development of multireference driven similarity renormalization group. (Doctoral Dissertation). University of Georgia. Retrieved from http://purl.galileo.usg.edu/uga_etd/li_chenyang_201505_phd
Chicago Manual of Style (16th Edition):
Li, Chenyang. “Applications of coupled cluster theory on infrared spectroscopy and the development of multireference driven similarity renormalization group.” 2015. Doctoral Dissertation, University of Georgia. Accessed March 29, 2020.
http://purl.galileo.usg.edu/uga_etd/li_chenyang_201505_phd.
MLA Handbook (7th Edition):
Li, Chenyang. “Applications of coupled cluster theory on infrared spectroscopy and the development of multireference driven similarity renormalization group.” 2015. Web. 29 Mar 2020.
Vancouver:
Li C. Applications of coupled cluster theory on infrared spectroscopy and the development of multireference driven similarity renormalization group. [Internet] [Doctoral dissertation]. University of Georgia; 2015. [cited 2020 Mar 29].
Available from: http://purl.galileo.usg.edu/uga_etd/li_chenyang_201505_phd.
Council of Science Editors:
Li C. Applications of coupled cluster theory on infrared spectroscopy and the development of multireference driven similarity renormalization group. [Doctoral Dissertation]. University of Georgia; 2015. Available from: http://purl.galileo.usg.edu/uga_etd/li_chenyang_201505_phd
Universidade de Brasília
4.
Elton Anderson Santos de Castro.
Estudo teórico da adsorção em aluminossilicatos.
Degree: 2007, Universidade de Brasília
URL: http://bdtd.bce.unb.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=2713
► Foram realizados cálculos de mecânica molecular, semi-empíricos e ab initio para o estudo de sistemas baseados em caulinita. As posições e freqüências dos hidrogênios foram…
(more)
▼ Foram realizados cálculos de mecânica molecular, semi-empíricos e
ab initio para o estudo de sistemas baseados em caulinita. As posições e freqüências dos hidrogênios foram estudadas na estrutura da caulinita. As posições dos hidrogênios são polêmicas, principalmente os hidrogênios entre as folhas octaédrica e tetraédrica. Também estudou-se a interação deste argilomineral com os hidrocarbonetos monoaromáticos benzeno, tolueno, etilbenzeno, o-xileno e pxileno, bem como com os metais pesados Cd2+, Cu2+, Zn2+, Hg2+ e Ni2+. A caulinita é conhecida pela sua capacidade adsorvente para moléculas orgânicas e metais pesados, sendo importante em técnicas de remediação ambiental. Modelos de aglomerados com 1, 2 e 3 unidades (Al2Si2O9H4) foram usados para estudar o desempenho dos conjuntos de base. A geometria da caulinita foi parcialmente otimizada. Para a otimização da posição do hidrogênio interno empregou-se os métodos RHF/3-21G* e B3LYP/3-21G* com 2 e 3 unidades (Al2Si2O9H4) da caulinita. O método híbrido ONIOM também foi usado com 3 unidades (Al2Si2O9H4) e RHF/3-21G* (ou B3LYP/3-21G*) na camada alta e 12 unidades (Al2Si2O9H4) e o campo de força Dreiding na camada baixa de teoria. Quando comparados com os valores experimentais, os resultados dos cálculos indicam que o ONIOM2(B3LYP/3-21G*:Dreiding) dá os melhores valores para a distância O-H e ângulos r e l, 0,993Å, 114,8 e 107,6, respectivamente. Os cálculos de freqüência para os hidrogênios externos e internos com o modelo de 3 unidades (Al2Si2O9H4) mostram que o método RHF/3-21G* se aproxima mais dos resultados experimentais do que os semi-empíricos AM1 e PM3. Estes três métodos apontam para um estiramento da hidroxila interna num número de onda menor do que os das hidroxilas externas. Os espectros teóricos produzidos com o AM1 mostram que há uma redução nas intensidades das bandas de estiramento das hidroxilas externas quando estas interagem com as moléculas BTEX. Também foi encontrado um deslocamento nas bandas de estiramento C-H destas moléculas. As energias de interação, obtidas com os métodos AM1, RHF e B3LYP para os complexos BTEX-Caulinita, sugerem que a adsorção acontece preferencialmente pela superfície hidroxilada da caulinita, ao invés da superfície dos oxigênios. Os métodos de Mülliken e ChelpG indicam que ocorre uma redistribuição nas cargas dos átomos mais próximos das superfícies da caulinita, ficando os hidrogênios mais eletronegativos e os carbonos, mais eletropositivos. Os mapas de potencial eletrostático para os complexos BTEX-Caulinita mostram também uma redistribuição de densidade quando as moléculas interagem com a superfície do argilomineral, corroborando com os resultados de Mülliken e ChelpG. Os orbitais moleculares do benzeno, tolueno e o-xileno adsorvidos pela caulinita sugerem que esta interação acontece através da nuvem p dos compostos aromáticos com as hidroxilas externas da caulinita. Para o estudo dos complexos de metais pesados-caulinita foi usado o ONIOM2(HF/3-21G*:UFF) e ONIOM2(B3LYP/3-21G*:UFF). Para estes modelos da caulinita de 2…
Advisors/Committee Members: Ricardo Gargano, Sílvia Cláudia Loureiro Dias, João Batista Lopes Martins, Jose Roberto dos Santos Politi, Elson Longo.
Subjects/Keywords: caulinita; adsorção; ab initio; QUIMICA
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APA (6th Edition):
Castro, E. A. S. d. (2007). Estudo teórico da adsorção em aluminossilicatos. (Thesis). Universidade de Brasília. Retrieved from http://bdtd.bce.unb.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=2713
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Castro, Elton Anderson Santos de. “Estudo teórico da adsorção em aluminossilicatos.” 2007. Thesis, Universidade de Brasília. Accessed March 29, 2020.
http://bdtd.bce.unb.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=2713.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Castro, Elton Anderson Santos de. “Estudo teórico da adsorção em aluminossilicatos.” 2007. Web. 29 Mar 2020.
Vancouver:
Castro EASd. Estudo teórico da adsorção em aluminossilicatos. [Internet] [Thesis]. Universidade de Brasília; 2007. [cited 2020 Mar 29].
Available from: http://bdtd.bce.unb.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=2713.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Castro EASd. Estudo teórico da adsorção em aluminossilicatos. [Thesis]. Universidade de Brasília; 2007. Available from: http://bdtd.bce.unb.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=2713
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Georgia
5.
Mullinax, Jimmy Wayne.
On the performance of density cumulant functional theory for capturing static correlation effects and ab initio computational studies of C2F4 and Ge4H4.
Degree: PhD, Chemistry, 2016, University of Georgia
URL: http://purl.galileo.usg.edu/uga_etd/mullinax_jimmy_w_201608_phd
► The performance of density cumulant functional theory (DCT) for capturing static correlation effects is reported and discussed. In this respect, DCT is competitive with the…
(more)
▼ The performance of density cumulant functional theory (DCT) for capturing static correlation effects is reported and discussed. In this respect, DCT is competitive with the popular coupled-cluster methods CCSD and CCSD(T), and the DCT natural orbital occupation numbers provide a convenient diagnostic for the appearance of multireference effects. In addition,
ab initio computational studies of tetrafluoroethylene (C2F4) and tetragermacyclobutadiene (Ge4H4) are reported. First, a theoretical investigation of the low-lying electronic states and conical intersections of C2F4 provides a complementary description of nonadiabatic processes that were recently probed by femtosecond photoionization spectroscopy. Second, a coupled-cluster study of the ground-state potential energy surface of Ge4H4 demonstrates its preference for unusual bonding arrangements in contrast to the planar ring structure of cyclobutadiene (C4H4).
Advisors/Committee Members: Henry F. Schaefer, III.
Subjects/Keywords: ab initio quantum chemistry
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APA (6th Edition):
Mullinax, J. W. (2016). On the performance of density cumulant functional theory for capturing static correlation effects and ab initio computational studies of C2F4 and Ge4H4. (Doctoral Dissertation). University of Georgia. Retrieved from http://purl.galileo.usg.edu/uga_etd/mullinax_jimmy_w_201608_phd
Chicago Manual of Style (16th Edition):
Mullinax, Jimmy Wayne. “On the performance of density cumulant functional theory for capturing static correlation effects and ab initio computational studies of C2F4 and Ge4H4.” 2016. Doctoral Dissertation, University of Georgia. Accessed March 29, 2020.
http://purl.galileo.usg.edu/uga_etd/mullinax_jimmy_w_201608_phd.
MLA Handbook (7th Edition):
Mullinax, Jimmy Wayne. “On the performance of density cumulant functional theory for capturing static correlation effects and ab initio computational studies of C2F4 and Ge4H4.” 2016. Web. 29 Mar 2020.
Vancouver:
Mullinax JW. On the performance of density cumulant functional theory for capturing static correlation effects and ab initio computational studies of C2F4 and Ge4H4. [Internet] [Doctoral dissertation]. University of Georgia; 2016. [cited 2020 Mar 29].
Available from: http://purl.galileo.usg.edu/uga_etd/mullinax_jimmy_w_201608_phd.
Council of Science Editors:
Mullinax JW. On the performance of density cumulant functional theory for capturing static correlation effects and ab initio computational studies of C2F4 and Ge4H4. [Doctoral Dissertation]. University of Georgia; 2016. Available from: http://purl.galileo.usg.edu/uga_etd/mullinax_jimmy_w_201608_phd
Penn State University
6.
Morrow, Christin Palombo.
A Computational Study of the Dissolution of Aluminosilicate
Minerals.
Degree: MS, Chemistry, 2008, Penn State University
URL: https://etda.libraries.psu.edu/catalog/9077
► The reactions of aluminosilicate clusters with water are investigated using ab-initio calculations. Reaction mechanisms for silicon terminated, Si-Obr-Al, sites as well as aluminum terminated, Al-Obr-Si,…
(more)
▼ The reactions of aluminosilicate clusters with water
are investigated using ab-initio calculations. Reaction mechanisms
for silicon terminated, Si-Obr-Al, sites as well as aluminum
terminated, Al-Obr-Si, sites were determined using
B3LYP/6-311+G(d,p) calculations. The calculated barrier heights for
protonated and neutral Al-Obr-Si sites are predicted to be lower
than those for Si-Obr-Si and Si-Obr-Al sites which mimics the
dissolution of these minerals, and the Si-Obr-Al dissolution
reactions proceeded in fundamentally the same fashion as those for
Si-Obr-Si [S. Nangia and B. J. Garrison, J. Phys. Chem. A 2008,
112, 2027]. The barrier heights for the rate determining step for
these reactions are calculated using the B3LYP, PBE1PBE, and M05-2X
functionals in combination with the 6-311+G(d,p) and MG3S basis
sets, and trends seen in the mechanistic calculations are repeated
with each computational method.
Subjects/Keywords: aluminosilicate; ab-initio; mechanism;
dissolution
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APA (6th Edition):
Morrow, C. P. (2008). A Computational Study of the Dissolution of Aluminosilicate
Minerals. (Masters Thesis). Penn State University. Retrieved from https://etda.libraries.psu.edu/catalog/9077
Chicago Manual of Style (16th Edition):
Morrow, Christin Palombo. “A Computational Study of the Dissolution of Aluminosilicate
Minerals.” 2008. Masters Thesis, Penn State University. Accessed March 29, 2020.
https://etda.libraries.psu.edu/catalog/9077.
MLA Handbook (7th Edition):
Morrow, Christin Palombo. “A Computational Study of the Dissolution of Aluminosilicate
Minerals.” 2008. Web. 29 Mar 2020.
Vancouver:
Morrow CP. A Computational Study of the Dissolution of Aluminosilicate
Minerals. [Internet] [Masters thesis]. Penn State University; 2008. [cited 2020 Mar 29].
Available from: https://etda.libraries.psu.edu/catalog/9077.
Council of Science Editors:
Morrow CP. A Computational Study of the Dissolution of Aluminosilicate
Minerals. [Masters Thesis]. Penn State University; 2008. Available from: https://etda.libraries.psu.edu/catalog/9077
Cornell University
7.
Schwarz, Kathleen.
Partitioning Molecular And Surface Environments: Practice And Approximations
.
Degree: 2014, Cornell University
URL: http://hdl.handle.net/1813/37083
► The physics of complex environments, though poorly understood, plays a critical role in a wide range of systems from the biological to the technological. Despite…
(more)
▼ The physics of complex environments, though poorly understood, plays a critical role in a wide range of systems from the biological to the technological. Despite the importance of these systems, they are poorly understood. The large required simulation size of complex environments currently makes them unsuitable for direct
ab initio calculations, yet inexpensive methods such as molecular modeling can be too approximate to describe the relevant chemical interactions. One resolution to this problem is to accurately describe specific interactions, and to inexpensively approximate interactions which are less relevant. The objective of this thesis is to determine to what extent one can partition systems into a molecule or surface treated at one level of theory, and a surrounding fluid or other molecular environment treated with another theory. I explore varying levels of theory, using different theories depending on the properties of the system and type of problem, and I address conflicts that arise from these choices when working to calculate properties of real systems. In the first project of the thesis, I strategically explore very different levels of theory for the solvent and solute to subvert the typical relationship found in computational work between cost and accuracy. In this thesis chapter, I combine a simple continuum description of a fluid with highly accurate quantum Monte Carlo calculations, to find solvation free energies of molecules. I find that this approach successfully preserves the accuracy of quantum Monte Carlo, while creating a framework for future calculations with more complicated fluid models. In the next two chapters, I investigate the continuum between expensive calculations of realistic systems, and inexpensive idealized systems. I examine the properties of lithium-sulfur battery systems and defects in pentacene thin films, using established polarizable continuum methods and density-functional theory, exploring the extent to which experimental realities alter the relevant observables. I am able to produce idealized voltammograms that capture key aspects of the battery experiments, and I also identify an experimentally observed defect in the pentacene. In the last chapter, I investigate the creation of a whole crystal from the sum of its parts, as I develop approximations of the dielectric matrix in molecular crystals. I successfully apply this to two crystals, creating dielectric band structures from molecular calculations that very closely resemble those from the entire crystal.
Advisors/Committee Members: Hennig, Richard G. (committeeMember), Hoffmann, Roald (committeeMember), Arias, Tomas A. (committeeMember).
Subjects/Keywords: ab initio electronic structure;
solvation
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APA (6th Edition):
Schwarz, K. (2014). Partitioning Molecular And Surface Environments: Practice And Approximations
. (Thesis). Cornell University. Retrieved from http://hdl.handle.net/1813/37083
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Schwarz, Kathleen. “Partitioning Molecular And Surface Environments: Practice And Approximations
.” 2014. Thesis, Cornell University. Accessed March 29, 2020.
http://hdl.handle.net/1813/37083.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Schwarz, Kathleen. “Partitioning Molecular And Surface Environments: Practice And Approximations
.” 2014. Web. 29 Mar 2020.
Vancouver:
Schwarz K. Partitioning Molecular And Surface Environments: Practice And Approximations
. [Internet] [Thesis]. Cornell University; 2014. [cited 2020 Mar 29].
Available from: http://hdl.handle.net/1813/37083.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Schwarz K. Partitioning Molecular And Surface Environments: Practice And Approximations
. [Thesis]. Cornell University; 2014. Available from: http://hdl.handle.net/1813/37083
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Mississippi State University
8.
Collier, Willard Earl.
A COMPUTATIONAL INVESTIGATION OF SOME POLYCALICENES AS NOVEL NONBENZENOID AROMATIC MOLECULES AND THE STRANGE CASE OF THE CYCLOPROPENYL ANION.
Degree: PhD, Chemistry, 2009, Mississippi State University
URL: http://sun.library.msstate.edu/ETD-db/theses/available/etd-04022009-213437/
;
► Polycalicenes are novel nonbenzenoid aromatic hydrocarbons made from calicene subunits. A host of related polycalicenes are possible by varying the number of calicenes and…
(more)
▼ Polycalicenes are novel nonbenzenoid aromatic hydrocarbons made from calicene subunits. A host of related polycalicenes are possible by varying the number of calicenes and the bonding motif of the calicenes (e.g. head-to-tail versus head-to-head). Polycalicenes might posses interesting and useful electrical, magnetic, and optical properties. Especially intriguing is that while calicene has never been synthesized, bicalicene 2, where two calicenes are bonded head-to-tail, has been synthesized by Yoshida et al. and found to be aromatic despite having a peripheral 16 ð electron count.
This study details a computational investigation of the aromaticity of some planar polycalicenes using the nucleus independent chemical shift (NICS) criterion of aromaticity. NICS values were calculated with HF/6-31+G(d,p) and B3LYP/6-31+G(d,p). Bicalicene 3, where two calicenes are bonded head-to-head, was shown to have a triplet ground state which required the calculation of NICS values using UB3LYP/6-31+G(d,p).
Also, the aromaticities of some belted polycalicenes were evaluated using NICS values calculated at 6-31G(d,p). The smaller basis set was used due to the increasing number of basis functions for the larger belted polycalicenes.
In addition, the electronic ground and excited states of the planar polycalicenes were also calculated. The electronic ground states were assigned using HF/6-31+G(d,p) and B3LYP/6-31+G(d,p). CCSD(T)/6-31G(d,p) calculations were used to confirm assignments. The electronic excited states were calculated using time dependent density functional theory (TDDFT) and B3LYP/6-31+G(d,p).
Recently, the reliability of the NICS criterion was questioned when it was claimed NICS found the cyclopropenyl anion to be aromatic. One part of this study details the examination of this claim and concluded that the earlier work was in error. The error was proven to arise from the failure to employ diffuse basis functions in the earlier work.
Advisors/Committee Members: Earl G.Alley (committee member), Charles U. Pittman, Jr. (chair), Steven R. Gwaltney (committee member), Andrzej Sygula (committee member), Stephen C. Foster (committee member).
Subjects/Keywords: aromaticity; NICS; ab initio
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APA (6th Edition):
Collier, W. E. (2009). A COMPUTATIONAL INVESTIGATION OF SOME POLYCALICENES AS NOVEL NONBENZENOID AROMATIC MOLECULES AND THE STRANGE CASE OF THE CYCLOPROPENYL ANION. (Doctoral Dissertation). Mississippi State University. Retrieved from http://sun.library.msstate.edu/ETD-db/theses/available/etd-04022009-213437/ ;
Chicago Manual of Style (16th Edition):
Collier, Willard Earl. “A COMPUTATIONAL INVESTIGATION OF SOME POLYCALICENES AS NOVEL NONBENZENOID AROMATIC MOLECULES AND THE STRANGE CASE OF THE CYCLOPROPENYL ANION.” 2009. Doctoral Dissertation, Mississippi State University. Accessed March 29, 2020.
http://sun.library.msstate.edu/ETD-db/theses/available/etd-04022009-213437/ ;.
MLA Handbook (7th Edition):
Collier, Willard Earl. “A COMPUTATIONAL INVESTIGATION OF SOME POLYCALICENES AS NOVEL NONBENZENOID AROMATIC MOLECULES AND THE STRANGE CASE OF THE CYCLOPROPENYL ANION.” 2009. Web. 29 Mar 2020.
Vancouver:
Collier WE. A COMPUTATIONAL INVESTIGATION OF SOME POLYCALICENES AS NOVEL NONBENZENOID AROMATIC MOLECULES AND THE STRANGE CASE OF THE CYCLOPROPENYL ANION. [Internet] [Doctoral dissertation]. Mississippi State University; 2009. [cited 2020 Mar 29].
Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-04022009-213437/ ;.
Council of Science Editors:
Collier WE. A COMPUTATIONAL INVESTIGATION OF SOME POLYCALICENES AS NOVEL NONBENZENOID AROMATIC MOLECULES AND THE STRANGE CASE OF THE CYCLOPROPENYL ANION. [Doctoral Dissertation]. Mississippi State University; 2009. Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-04022009-213437/ ;
9.
Subênia Karine de Medeiros.
Sistemas Nanoestruturados: Heteroestruturas Quasi-Periódicas de Nitretos e Cálculos Ab initio em Polimorfos CaCO3.
Degree: 2007, Universidade Federal do Rio Grande do Norte
URL: http://bdtd.bczm.ufrn.br/tedesimplificado//tde_busca/arquivo.php?codArquivo=1189
► The physical properties and the excitations spectrum in oxides and semiconductors materials are presented in this work, whose the first part presents a study on…
(more)
▼ The physical properties and the excitations spectrum in oxides and semiconductors materials are presented in this work, whose the first part presents a study on the confinement of optical phonons in artificial systems based on III-V nitrides, grown in periodic and quasiperiodic forms. The second part of this work describes the Ab initio calculations which were carried out to obtain the optoeletronic properties of Calcium Oxide (CaO) and Calcium Carbonate (CaCO3) crystals. For periodic and quasi-periodic superlattices, we present some dynamical properties related to confined optical phonons (bulk and surface), obtained through simple theories, such as the dielectric continuous model, and using techniques such as the transfer-matrix method. The localization character of confined optical phonon modes, the magnitude of the bands in the spectrum and the power laws of these structures are presented as functions of the generation number of sequence. The ab initio calculations have been carried out using the CASTEP software (Cambridge Total Sequential Energy Package), and they were based on ultrasoft-like pseudopotentials and Density Functional Theory (DFT). Two dierent geometry optimizations have been eectuated for CaO crystals and CaCO3 polymorphs, according to LDA (local density approximation) and GGA (generalized gradient approximation) approaches, determining several properties, e. g. lattice parameters, bond length, electrons density, energy band structures, electrons density of states, eective masses and optical properties, such as dielectric constant, absorption, reectivity, conductivity and refractive index. Those results were employed to investigate the confinement of excitons in spherical [email protected] and [email protected] quantum dots and in calcium carbonate nanoparticles, and were also employed in investigations of the photoluminescence spectra of CaCO3 crystal
As propriedades físicas e o espectro de excitações em materiais óxidos e semicondutores são apresentados neste trabalho, composto primeiramente por um estudo sobre o confinamento de fonons ópticos em sistemas artificiais baseados em nitretos III-V, crescidos periodicamente e quasi-periodicamente. A segunda parte deste trabalho descreve cálculos de primeiros princípios realizados para a obtenção de propriedades optoeletrônicas em cristais de Óxido de Cálcio (CaO) e Carbonato de Cálcio (CaCO3). Para as super- redes periódicas e quasi-periódicas apresentamos aqui algumas propriedades dinâmicas relacionadas a fonons ópticos (de volume e de superfície) confinados obtidos através de teorias simples como o modelo do dielétrico contínuo e a utilização de técnicas como a aproximação da matriz transferência. O caráter de localização dos modos de fonons ópticos confinados, a magnitude das bandas no espectro e a lei de escalas dessas estruturas como função do número de geração das sequências substitucionais são apresentadas. Os cálculos ab initio foram realizados utilizando o software CASTEP (Cambridge Sequential Total Energy Package) baseados nos métodos de…
Advisors/Committee Members: Ewerton Wagner Caetano, Valder Nogueira Freire, Dory Hélio Aires de Lima Anselmo, Luciano Rodrigues da Silva, Eudenilson Lins de Albuquerque.
Subjects/Keywords: Ab initio; Heteroestruturas; Hidretos; Nanoescalas; FISICA; Heterostructures; Hydrides; Ab initio; Nanoscales
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APA (6th Edition):
Medeiros, S. K. d. (2007). Sistemas Nanoestruturados: Heteroestruturas Quasi-Periódicas de Nitretos e Cálculos Ab initio em Polimorfos CaCO3. (Thesis). Universidade Federal do Rio Grande do Norte. Retrieved from http://bdtd.bczm.ufrn.br/tedesimplificado//tde_busca/arquivo.php?codArquivo=1189
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Medeiros, Subênia Karine de. “Sistemas Nanoestruturados: Heteroestruturas Quasi-Periódicas de Nitretos e Cálculos Ab initio em Polimorfos CaCO3.” 2007. Thesis, Universidade Federal do Rio Grande do Norte. Accessed March 29, 2020.
http://bdtd.bczm.ufrn.br/tedesimplificado//tde_busca/arquivo.php?codArquivo=1189.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Medeiros, Subênia Karine de. “Sistemas Nanoestruturados: Heteroestruturas Quasi-Periódicas de Nitretos e Cálculos Ab initio em Polimorfos CaCO3.” 2007. Web. 29 Mar 2020.
Vancouver:
Medeiros SKd. Sistemas Nanoestruturados: Heteroestruturas Quasi-Periódicas de Nitretos e Cálculos Ab initio em Polimorfos CaCO3. [Internet] [Thesis]. Universidade Federal do Rio Grande do Norte; 2007. [cited 2020 Mar 29].
Available from: http://bdtd.bczm.ufrn.br/tedesimplificado//tde_busca/arquivo.php?codArquivo=1189.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Medeiros SKd. Sistemas Nanoestruturados: Heteroestruturas Quasi-Periódicas de Nitretos e Cálculos Ab initio em Polimorfos CaCO3. [Thesis]. Universidade Federal do Rio Grande do Norte; 2007. Available from: http://bdtd.bczm.ufrn.br/tedesimplificado//tde_busca/arquivo.php?codArquivo=1189
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
10.
Florence Pereira Novais Antunes.
Estudo ab initio da adsorção de organofosforados em TiO2 e Ti(1-x)ZrxO2.
Degree: 2010, Universidade Federal de Juiz de Fora
URL: http://www.bdtd.ufjf.br/tde_busca/arquivo.php?codArquivo=739
► O estudo da degradação de organofosforados é de suma importância tanto na área ambiental quanto na de defesa química. Tem sido descrito na literatura exaustivos…
(more)
▼ O estudo da degradação de organofosforados é de suma importância tanto na área ambiental quanto na de defesa química. Tem sido descrito na literatura exaustivos estudos sobre degradação de organofosforados relacionados à agricultura. Um desses estudos leva em conta o uso da luz na degradação de um dos organofosforados mais usados na agricultura como pesticida, o paration. O processo chamado de fotocátalise heterogênea, envolve a ativação de um semicondutor (geralmente TiO2) por luz solar ou artificial. A absorção de fótons com energia superior à energia de bandgap resulta na promoção de um elétron da banda de valência para banda de condução com geração concomitante de um buraco (hole) na banda de valência. Estes buracos mostram potenciais suficientemente positivos, capazes de formar radicais hidroxila a partir de moléculas de água adsorvidas na superfície do semicondutor, os quais podem subseqüentemente oxidar contaminantes orgânicos. O objetivo deste trabalho foi determinar a influência da substituição de titânio por zircônio em TiO2 na adsorção de organofosforados, que é uma das etapas de degradação desses compostos. Para isso foram determinadas as estruturas, propriedades eletrônicas e vibracionais de organofosforados adsorvidos em TiO2 (101) anatase e Ti(1-x)ZrxO2. Os compostos estudados e adsorvidos são: Paration, Sarin e VX. A idéia foi propor uma técnica bem descrita experimentalmente para degradação do paration, para possível detoxificação de organofosforados usados como armas químicas, no caso, o Sarin e o VX. Foi feito o estudo da adsorção dos organofosforados em titânia substituída com zircônio na proporção Ti(1-x)ZrxO2, levando em conta que modificações na estrutura do catalisador aumentam a atividade fotocatalítica. Cálculos feitos verificam a contribuição energética da etapa de adsorção e comparando com a estrutura do catalisador puro foi possível obter melhora nesta etapa. Foram obtidas energias de fisissorção e quimissorção nas diferentes posições possíveis. O tipo de adsorção foi confirmado com estudos de diferença de carga eletrônica. Foi obtido também o estudo de frequência vibracional. A partir dos resultados, concluiu-se que a adsorção se processou de maneira mais efetiva nos casos em que foi usado o catalisador com zircônio, com energia de adsorção de -25,71kcal/mol, para o p-VX adsorvido. Em titânia pura a energia de adsorção de p-VX foi de -18,14kcal/mol. As diferenças de densidade de carga eletrônica também confirmaram os resultados
The study of degradation of organophosphorous is critical both in the environmental area as in chemical defense. Has been described in the literature studies on degradation of organophosphorous related to agriculture. One of the study considers the use of light in a degradation of the organophosphorous pesticide used in agriculture: the parathion. The process called heterogeneous photocatalysis involves the activation of a semiconductor (usually TiO 2) by sunlight or artificial. The absorption of photons with energy higher than the energy band gap results in…
Advisors/Committee Members: Itamar Borges Junior, Clarissa Oliveira da Silva, Socrates de Oliveira Dantas, Alexandre Amaral Leitao.
Subjects/Keywords: adsorção; FISICO-QUIMICA; ab initio; organofosforados; adsorption; ab initio; organophosphorous
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APA (6th Edition):
Antunes, F. P. N. (2010). Estudo ab initio da adsorção de organofosforados em TiO2 e Ti(1-x)ZrxO2. (Thesis). Universidade Federal de Juiz de Fora. Retrieved from http://www.bdtd.ufjf.br/tde_busca/arquivo.php?codArquivo=739
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Antunes, Florence Pereira Novais. “Estudo ab initio da adsorção de organofosforados em TiO2 e Ti(1-x)ZrxO2.” 2010. Thesis, Universidade Federal de Juiz de Fora. Accessed March 29, 2020.
http://www.bdtd.ufjf.br/tde_busca/arquivo.php?codArquivo=739.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Antunes, Florence Pereira Novais. “Estudo ab initio da adsorção de organofosforados em TiO2 e Ti(1-x)ZrxO2.” 2010. Web. 29 Mar 2020.
Vancouver:
Antunes FPN. Estudo ab initio da adsorção de organofosforados em TiO2 e Ti(1-x)ZrxO2. [Internet] [Thesis]. Universidade Federal de Juiz de Fora; 2010. [cited 2020 Mar 29].
Available from: http://www.bdtd.ufjf.br/tde_busca/arquivo.php?codArquivo=739.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Antunes FPN. Estudo ab initio da adsorção de organofosforados em TiO2 e Ti(1-x)ZrxO2. [Thesis]. Universidade Federal de Juiz de Fora; 2010. Available from: http://www.bdtd.ufjf.br/tde_busca/arquivo.php?codArquivo=739
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Universidade Federal do Maranhão
11.
ANDRÉ HADAD CORTEZ.
PROPRIEDADES ELETRÔNICAS DE NANOFIOS DE SI-GE COM SEQUENCIAMENTO DE FIBONACCI E RANDÔMICO.
Degree: 2012, Universidade Federal do Maranhão
URL: http://www.tedebc.ufma.br//tde_busca/arquivo.php?codArquivo=891
► In this work we address a theoretical calculation of the electronic spectra in Si-Ge atomic chain that is arranged in a Fibonacci quasi-periodic sequence, by…
(more)
▼ In this work we address a theoretical calculation of the electronic spectra in Si-Ge atomic chain that is arranged in a Fibonacci quasi-periodic sequence, by using semi-empirical quantum method based on Hückel extended model. We apply the Fibonacci substitutional sequences in the atomic building blocks A(Si) and B(Ge) through the in ation rule or recursion relation. In our ab initio calculations we use only a single point which is the suficient condition to consider all the orbitals and charge distribution across the entire system. Although the calculations presented here are more complete than the models adopted in the literature which take into account the electronic interaction, up to the second and third neighbors, an interesting property remains in their electronic spectra: the fractality (which is the main signature of this kind of system). We discuss this fractality of the spectra and we compare them with the randomic arrangement of Si-Ge atomic chain, and with previous results based on the tight-binding approximation of Schorödinger equation considering until the nearest neighbor.
Neste trabalho abordamos um cálculo teórico dos espectros eletrônicos em cadeia atômica de Si-Ge que e organizado em uma sequência Fibonacci quasi-periódica, usando o método semi-emíprico com base no modelo quântico Hückel estendido. Nos aplicamos as sequências substitucional de Fibonacci nos blocos de construção atômica A(Si) e B(Ge) através da relação de recursão. Em nossos cálculos ab initio, usamos apenas um único ponto, que é a condição suficiente para considerar todos os orbitais e a distribuição de cargas em todo o sistema. Embora os cálculos apresentados aqui sejam mais completos do que os modelos adotados na literatura que levam em conta a interação eletrônica, ate segundos e terceiros vizinhos, uma propriedade interessante permanece em seus espectros eletrônicos: a fractalidade (que e a assinatura principal deste tipo de sistema). Discutimos essa fractalidade dos espectros e as comparamos com os espectros de cadeia atômica randômica de Si-Ge, e, também, com os resultados prévios baseados na aproximação tight-binding da equação Schorödinger considerando até o vizinho mais próximo.
Advisors/Committee Members: David Lima Azevedo.
Subjects/Keywords: Nanofios; Finonacci; Fractalidade; Ab initio; FISICA; Nanowires; Ab initio; Fibonacci; Fractality
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CSE |
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APA (6th Edition):
CORTEZ, A. H. (2012). PROPRIEDADES ELETRÔNICAS DE NANOFIOS DE SI-GE COM SEQUENCIAMENTO DE FIBONACCI E RANDÔMICO. (Thesis). Universidade Federal do Maranhão. Retrieved from http://www.tedebc.ufma.br//tde_busca/arquivo.php?codArquivo=891
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
CORTEZ, ANDRÉ HADAD. “PROPRIEDADES ELETRÔNICAS DE NANOFIOS DE SI-GE COM SEQUENCIAMENTO DE FIBONACCI E RANDÔMICO.” 2012. Thesis, Universidade Federal do Maranhão. Accessed March 29, 2020.
http://www.tedebc.ufma.br//tde_busca/arquivo.php?codArquivo=891.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
CORTEZ, ANDRÉ HADAD. “PROPRIEDADES ELETRÔNICAS DE NANOFIOS DE SI-GE COM SEQUENCIAMENTO DE FIBONACCI E RANDÔMICO.” 2012. Web. 29 Mar 2020.
Vancouver:
CORTEZ AH. PROPRIEDADES ELETRÔNICAS DE NANOFIOS DE SI-GE COM SEQUENCIAMENTO DE FIBONACCI E RANDÔMICO. [Internet] [Thesis]. Universidade Federal do Maranhão; 2012. [cited 2020 Mar 29].
Available from: http://www.tedebc.ufma.br//tde_busca/arquivo.php?codArquivo=891.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
CORTEZ AH. PROPRIEDADES ELETRÔNICAS DE NANOFIOS DE SI-GE COM SEQUENCIAMENTO DE FIBONACCI E RANDÔMICO. [Thesis]. Universidade Federal do Maranhão; 2012. Available from: http://www.tedebc.ufma.br//tde_busca/arquivo.php?codArquivo=891
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Universidade do Rio Grande do Norte
12.
Medeiros, Subênia Karine de.
Sistemas Nanoestruturados: Heteroestruturas Quasi-Periódicas de Nitretos e Cálculos Ab initio em Polimorfos
CaCO3
.
Degree: 2007, Universidade do Rio Grande do Norte
URL: http://repositorio.ufrn.br/handle/123456789/16649
► The physical properties and the excitations spectrum in oxides and semiconductors materials are presented in this work, whose the first part presents a study on…
(more)
▼ The physical properties and the excitations spectrum in oxides and semiconductors materials are presented in this work, whose the first part presents a study on the confinement of optical phonons in artificial systems based on III-V nitrides, grown in periodic and quasiperiodic forms. The second part of this work describes the
Ab initio calculations which were carried out to obtain the optoeletronic properties of Calcium Oxide (CaO) and Calcium Carbonate (CaCO3) crystals. For periodic and quasi-periodic superlattices, we present some dynamical properties related to confined optical phonons (bulk and surface), obtained through simple theories, such as the dielectric continuous model, and using techniques such as the transfer-matrix method. The localization character of confined optical phonon modes, the magnitude of the bands in the spectrum and the power laws of these structures are presented as functions of the generation number of sequence.
The
ab initio calculations have been carried out using the CASTEP software (Cambridge Total Sequential Energy Package), and they were based on ultrasoft-like pseudopotentials and Density Functional Theory (DFT). Two di®erent geometry optimizations have been e®ectuated for CaO crystals and CaCO3 polymorphs, according to LDA (local density approximation) and GGA (generalized gradient approximation) approaches, determining several properties, e. g. lattice parameters, bond length, electrons density, energy band structures, electrons density of states, e®ective masses and optical properties, such as dielectric constant, absorption, re°ectivity, conductivity and refractive index. Those results were employed to investigate the confinement of excitons in spherical
[email protected] and
[email protected] quantum dots and in calcium carbonate nanoparticles, and were also
employed in investigations of the photoluminescence spectra of CaCO3 crystal
Advisors/Committee Members: Albuquerque, Eudenilson Lins de (advisor), CPF:05011124487 (advisor), http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4783172H5 (advisor), Freire, Valder Nogueira (advisor), CPF:12105473334 (advisor), http://lattes.cnpq.br/8647922327100953 (advisor).
Subjects/Keywords: Heteroestruturas;
Hidretos;
Ab initio;
Nanoescalas;
Heterostructures;
Hydrides;
Ab initio;
Nanoscales
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APA ·
Chicago ·
MLA ·
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CSE |
Export
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Manager
APA (6th Edition):
Medeiros, S. K. d. (2007). Sistemas Nanoestruturados: Heteroestruturas Quasi-Periódicas de Nitretos e Cálculos Ab initio em Polimorfos
CaCO3
. (Thesis). Universidade do Rio Grande do Norte. Retrieved from http://repositorio.ufrn.br/handle/123456789/16649
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Medeiros, Subênia Karine de. “Sistemas Nanoestruturados: Heteroestruturas Quasi-Periódicas de Nitretos e Cálculos Ab initio em Polimorfos
CaCO3
.” 2007. Thesis, Universidade do Rio Grande do Norte. Accessed March 29, 2020.
http://repositorio.ufrn.br/handle/123456789/16649.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Medeiros, Subênia Karine de. “Sistemas Nanoestruturados: Heteroestruturas Quasi-Periódicas de Nitretos e Cálculos Ab initio em Polimorfos
CaCO3
.” 2007. Web. 29 Mar 2020.
Vancouver:
Medeiros SKd. Sistemas Nanoestruturados: Heteroestruturas Quasi-Periódicas de Nitretos e Cálculos Ab initio em Polimorfos
CaCO3
. [Internet] [Thesis]. Universidade do Rio Grande do Norte; 2007. [cited 2020 Mar 29].
Available from: http://repositorio.ufrn.br/handle/123456789/16649.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Medeiros SKd. Sistemas Nanoestruturados: Heteroestruturas Quasi-Periódicas de Nitretos e Cálculos Ab initio em Polimorfos
CaCO3
. [Thesis]. Universidade do Rio Grande do Norte; 2007. Available from: http://repositorio.ufrn.br/handle/123456789/16649
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
13.
Khalil, Hossain.
Highly accurate studies of the rovibronic states of small size radicals : Etudes très précises des états rovibroniques des radicaux de petites tailles.
Degree: Docteur es, Chimie, 2012, Université Paris-Est
URL: http://www.theses.fr/2012PEST1028
► Des calculs ab initio basés sur des méthodes hautement corrélées ont été utilisés pour étudier la structure rovibronique et la spectroscopie des radicaux de 2…
(more)
▼ Des calculs ab initio basés sur des méthodes hautement corrélées ont été utilisés pour étudier la structure rovibronique et la spectroscopie des radicaux de 2 à 4 atomes. Pour les molécules CaO, OH, CaH, CaO+ et CaO-, les constantes spectroscopiques calculées sont en accord avec les données expérimentales. L'étude de ces fragments diatomiques est essentielle pour comprendre la structure électronique des isomères du monohydroxyde de calcium (CaOH-HCaO). Le système le plus complexe, parmi ces radicaux diatomiques, est le monoxyde de calcium CaO en raison de la densité élevée des premiers états électroniques. Les énergies rovibrationnelles de ces états ont été calculées sur la base des énergies potentielles obtenues avec un niveau élevé de précision, en tenant compte des couplages entre les moments angulaires et du couplage spin-orbite. Nos résultats sont très proches des résultats expérimentaux. La complexité de l'étude d'un tel système est aussi présente dans le radical ketenyl HCCO à cause de l'effet Renner-Teller qui couple l'état fondamental et le premier état excité. L'effet Renner-Teller dans HCCO a été étudié à l'aide d'une approche variationnelle traitant tous les degrés de liberté. Les coordonnées de valence ont été utilisées pour construire les deux surfaces d'énergie potentielle à six dimensions. Les niveaux rovibroniques les plus bas ont été obtenus pour différentes valeurs du moment angulaire total
Highly correlated ab initio methodologies were used to investigate the rovibronic structure and the spectroscopy of 2 to 4 atoms radicals. For the CaO, OH, CaH, CaO+ and CaO− molecules, our computed spectroscopic constants are in good agreement with the experimental ones. The study of these diatomic fragments is essential to investigate the calcium monohydroxide isomers (CaOH-HCaO). The most complex system among these diatomic radicals is the calcium monoxide radical CaO due to high density low lying electronic states. The rovibrational energies of these states have been calculated, based on the potential energies obtained at high level of accuracy, taking into account the angular momentum and spin orbit couplings and found to be in a very good agreement with the experimental results. The complexity in studying such a system is again present in the ketenyl radical HCCO with highly coupled ground and first excited states. The Renner-Teller effect of HCCO is studied using a variational approach including all degrees of freedom. Valence coordinates have been used to fit both potential energy surfaces varying the six degrees of freedom. The low-lying rovibronic levels have been determined for different values of the total angular momentum
Advisors/Committee Members: Destandau-Léonard, Céline (thesis director).
Subjects/Keywords: Ab initio; Spectroscopie; Rovibronique; Ab initio; Spectroscopy; Rovibronic
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CSE |
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Manager
APA (6th Edition):
Khalil, H. (2012). Highly accurate studies of the rovibronic states of small size radicals : Etudes très précises des états rovibroniques des radicaux de petites tailles. (Doctoral Dissertation). Université Paris-Est. Retrieved from http://www.theses.fr/2012PEST1028
Chicago Manual of Style (16th Edition):
Khalil, Hossain. “Highly accurate studies of the rovibronic states of small size radicals : Etudes très précises des états rovibroniques des radicaux de petites tailles.” 2012. Doctoral Dissertation, Université Paris-Est. Accessed March 29, 2020.
http://www.theses.fr/2012PEST1028.
MLA Handbook (7th Edition):
Khalil, Hossain. “Highly accurate studies of the rovibronic states of small size radicals : Etudes très précises des états rovibroniques des radicaux de petites tailles.” 2012. Web. 29 Mar 2020.
Vancouver:
Khalil H. Highly accurate studies of the rovibronic states of small size radicals : Etudes très précises des états rovibroniques des radicaux de petites tailles. [Internet] [Doctoral dissertation]. Université Paris-Est; 2012. [cited 2020 Mar 29].
Available from: http://www.theses.fr/2012PEST1028.
Council of Science Editors:
Khalil H. Highly accurate studies of the rovibronic states of small size radicals : Etudes très précises des états rovibroniques des radicaux de petites tailles. [Doctoral Dissertation]. Université Paris-Est; 2012. Available from: http://www.theses.fr/2012PEST1028
14.
Maatouk, Amira.
Étude de la croissance des nanotubes de carbone catalysée par le fer : Structures and properties of small iron-doped carbon clusters.
Degree: Docteur es, Chimie, 2012, Université Paris-Est
URL: http://www.theses.fr/2012PEST1147
► L’étude de réactions chimiques, tout comme le calcul de propriétés thermodynamiques, sont des enjeux capitaux de la chimie moderne. L’évolution des instruments et techniques expérimentales…
(more)
▼ L’étude de réactions chimiques, tout comme le calcul de propriétés thermodynamiques, sont des enjeux capitaux de la chimie moderne. L’évolution des instruments et techniques expérimentales permet des mesures de plus en plus précises de ces grandeurs, pour des systèmes de plus en plus complexes. L’intérêt croissant pour l’étude du milieu interstellaire et des atmosphères planétaires se révèle également être un défi très important dans les décennies à venir. Les difficultés rencontrées lors de l’analyse de ces expériences (ou mesures), nécessitent souvent l’intervention de simulations numériques de manière à éclairer ces observations. Une autre utilisation du calcul est de prédire des paramètres moléculaires et spectroscopiques d’espèces instables difficiles à produire au laboratoire. Les outils actuels de la chimie théorique
ab initio sont des moyens précieux pour la prédiction et l’interprétation de résultats expérimentaux ou de mesures astrophysiques et atmosphériques. Ces techniques de simulation ont connu des développements importants au cours des dernières décennies. Les progrès récents en matière de calculs d’interaction de configurations de grande taille permettent d’inclure une grande partie de l’énergie de corrélation. Le temps de calcul et la taille mémoire des ordinateurs restent cependant des limites importantes qui ne permettent pas d’effectuer des interactions de configurations totales dans une base suffisamment grande pour contenir la physique des systèmes étudiés au delà de petites molécules. Cet état de fait conduit à s’intéresser à des méthodes moins coûteuses comme celles des perturbations, les interactions de configurations tronquées et le Coupled Cluster, permettant d’inclure une partie de la corrélation électronique à un coût moins élevé en temps de calcul. Ce sont ces méthodes qui ont été utilisées dans ce travail pour déterminer théoriquement les paramètres moléculaires et spectroscopiques des systèmes MgO, MgO+, FeC2, FeC2+ et FeC2- avec le maximum de précision possible.Dans un premier temps, nous avons étudié la molécule MgO. C’est un système de choix car, il permet de s’initier aux méthodes de calcul
ab initio sur les systèmes moléculaires les plus simples (diatomiques), de tester et de comprendre ces méthodes (différentes approximations, validité, précision, …) et de bien interpréter les résultats obtenus (formation de la liaison chimique et des états moléculaires, leur symétrie, leurs couplages, leur stabilité, leur spectroscopie, …) surtout qu’il a fait l’objet de plusieurs études théoriques et expérimentales. Pour profiter de notre savoir-faire pour les molécules diatomiques nous avons étudié le système MgO+ qui a fait l’objet de notre deuxième article que sera présenté en annexe.Dans un second temps, nous avons visé les systèmes moléculaires de type FenCm afin de comprendre la croissance et la dynamique des nanotubes de carbone catalysée par le Fer. Le système diatomique FeC fait l’objet de plusieurs études théoriques et expérimentales. La plus récente est celle fourni par Demeter Tzeli…
Advisors/Committee Members: Hochlaf, Majdi (thesis director).
Subjects/Keywords: Ab initio; Structure électronique; Spectroscopie; Ab initio; Electronic structure; Spectroscopy
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APA (6th Edition):
Maatouk, A. (2012). Étude de la croissance des nanotubes de carbone catalysée par le fer : Structures and properties of small iron-doped carbon clusters. (Doctoral Dissertation). Université Paris-Est. Retrieved from http://www.theses.fr/2012PEST1147
Chicago Manual of Style (16th Edition):
Maatouk, Amira. “Étude de la croissance des nanotubes de carbone catalysée par le fer : Structures and properties of small iron-doped carbon clusters.” 2012. Doctoral Dissertation, Université Paris-Est. Accessed March 29, 2020.
http://www.theses.fr/2012PEST1147.
MLA Handbook (7th Edition):
Maatouk, Amira. “Étude de la croissance des nanotubes de carbone catalysée par le fer : Structures and properties of small iron-doped carbon clusters.” 2012. Web. 29 Mar 2020.
Vancouver:
Maatouk A. Étude de la croissance des nanotubes de carbone catalysée par le fer : Structures and properties of small iron-doped carbon clusters. [Internet] [Doctoral dissertation]. Université Paris-Est; 2012. [cited 2020 Mar 29].
Available from: http://www.theses.fr/2012PEST1147.
Council of Science Editors:
Maatouk A. Étude de la croissance des nanotubes de carbone catalysée par le fer : Structures and properties of small iron-doped carbon clusters. [Doctoral Dissertation]. Université Paris-Est; 2012. Available from: http://www.theses.fr/2012PEST1147
Brno University of Technology
15.
Pleskot, Ondřej.
Prvoprincipiální studium stability krystalů pevných látek
.
Degree: 2014, Brno University of Technology
URL: http://hdl.handle.net/11012/33291
► Práce se zabývá modelováním elektronové struktury v krystalech pevných látek. Konkrétně jsou prvoprincipiálním kódem VASP spočteny hustoty valenčních elektronů a hustoty stavů tří krystalů, reprezentující…
(more)
▼ Práce se zabývá modelováním elektronové struktury v krystalech pevných látek. Konkrétně jsou prvoprincipiálním kódem VASP spočteny hustoty valenčních elektronů a hustoty stavů tří krystalů, reprezentující tři typy vazeb. Jedná se o vazbu kovovou v krystalu hliníku, o vazbu kovalentní v krystalu diamantu a o vazbu iontovou v krystalu soli kamenné. Z vypočtených hodnot napětí a energie jsou následně určeny některé makroskopické parametry krystalů, jako jsou rovnovážný mřížkový parametr, modul objemové pružnosti a mez pevnosti při izotropním tahu.; This work deals with a modeling of an electronic structure of solid crystals. Specifically, densities of valence electrons, and the density of states are calculated using first-principles code VASP for three crystals representing three different types of bonding. These are the metal bonding in a crystal of aluminum, the covalent bonding in a diamond crystal, and an ionic bonding in the crystal of rock salt. From calculated values of stress and crystal energy are then determined some macroscopic parameters of crystals, such as the equilibrium lattice parameter, the bulk modulus and the theoretical strength under isotropic tension.
Advisors/Committee Members: Černý, Miroslav (advisor).
Subjects/Keywords: Ab initio;
prvoprincipiální;
VASP;
Ab initio;
first-principles;
VASP
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APA (6th Edition):
Pleskot, O. (2014). Prvoprincipiální studium stability krystalů pevných látek
. (Thesis). Brno University of Technology. Retrieved from http://hdl.handle.net/11012/33291
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Pleskot, Ondřej. “Prvoprincipiální studium stability krystalů pevných látek
.” 2014. Thesis, Brno University of Technology. Accessed March 29, 2020.
http://hdl.handle.net/11012/33291.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Pleskot, Ondřej. “Prvoprincipiální studium stability krystalů pevných látek
.” 2014. Web. 29 Mar 2020.
Vancouver:
Pleskot O. Prvoprincipiální studium stability krystalů pevných látek
. [Internet] [Thesis]. Brno University of Technology; 2014. [cited 2020 Mar 29].
Available from: http://hdl.handle.net/11012/33291.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Pleskot O. Prvoprincipiální studium stability krystalů pevných látek
. [Thesis]. Brno University of Technology; 2014. Available from: http://hdl.handle.net/11012/33291
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
16.
Iagupov, Ilia.
Numerical design of meta-materials for photovoltaic applications : Design numérique de métamatériaux pour des applications photovoltaïques.
Degree: Docteur es, Physique de la matière condensée, 2018, Université Paris-Saclay (ComUE)
URL: http://www.theses.fr/2018SACLX117
► Le but de la thèse était de simuler le spectre d'absorption de méta-matériaux pour les applications photovoltaïques. Par méta-matériaux, nous entendons une assemblée d'objets de…
(more)
▼ Le but de la thèse était de simuler le spectre d'absorption de méta-matériaux pour les applications photovoltaïques. Par méta-matériaux, nous entendons une assemblée d'objets de taille nanométrique situés à distance mésoscopique. L'idée sous-jacente est qu'en modifiant la taille du nano-objet et l'arrangement géométrique, on peut ajuster le seuil d'absorption. Pour calculer ces quantités, j'ai utilisé l'état de l'art du formalisme, c'est-à-dire des méthodes
ab initio.La première étape du travail a été dédiée au calcul de l'absorption d'un objet isolé (tranche de silicium, graphène, hBN). Dans le cadre de codes périodiques, on utilise une supercellule avec du vide pour isoler l'objet, et une méthode a été développée précédemment dans le groupe de Spectroscopie Théorique du LSI, pour obtenir des résultats indépendants du vide. Elle est appelée Selected-G, et a été appliquée avec succès aux surfaces de silicium. Pour une tranche isolée, une expression modifiée du potentiel coulombien dans l'espace réciproque, appelé "slab potential", doit être utilisée. Pour valider l'utilisation du potentiel de slab pour le calcul de la matrice diélectrique microscopique, j'ai simulé les spectres de perte d'énergie d'électrons pour des empilements de quelques plans de graphène, et reproduit avec succès les données expérimentales disponibles. Cela a offert la possibilité d'étudier la dispersion du plasmon d'un plan de graphène, et discuter la nature des excitations électroniques dans ce système (transitions interband ou plasmon 2D).La second étape a été consacrée à l'étude du spectre d'absorption d'une assemblée de tranches en interaction. Comme il a été mis en évidence que le formalisme de supercellule agit comme une théorie de matériau moyen avec du vide, avec l'effet erroné d'avoir des spectres dépendant de la taille de la supercellule, j'ai renversé la procédure pour extraire le spectre de la tranche en interaction, affranchi du problème du vide. La faisabilité a été démontrée sur les tranches de hBN, dont le caractère semi-conducteur à large bande interdite évite les instabilités numériques.Cela a permis de comprendre la raison pour laquelle l'absorption de la tranche en interaction de silicium apparaît à plus basse énergie que celle du matériau massif: cela vient de la présence des états de surface dans la bande interdite de la structure de bandes du massif. Néanmoins, la différence avec la tranche isolée doit être encore étudiée.La troisième partie a été dédiée à l'étude de matériaux utilisés, ou candidats, aux applications photovoltaïques comme InP et InSe. J'ai étudié dans un premier temps les structures de bandes des massifs. Pour corriger la sous-estimation de la bande interdite calculée dans l'approximation de la densité locale (LDA), j'ai calculé les corrections GW, et utilisé la fonctionnelle d'échange et corrélation de Heyd-Scuseria-Ernzerhof (HSE). Le spectre d'absorption de InP massif a été calculé en résolvant l'équation de Bethe-Salpeter, qui permet de tenir compte des effets excitoniques. Comme ce calcul est très…
Advisors/Committee Members: Véniard, Valérie (thesis director).
Subjects/Keywords: Ab-initio; Métamatériaux; Photovoltaïque numérique; Ab-initio; Metamaterials; Photovoltaics; 621.312 44
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MLA ·
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CSE |
Export
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APA (6th Edition):
Iagupov, I. (2018). Numerical design of meta-materials for photovoltaic applications : Design numérique de métamatériaux pour des applications photovoltaïques. (Doctoral Dissertation). Université Paris-Saclay (ComUE). Retrieved from http://www.theses.fr/2018SACLX117
Chicago Manual of Style (16th Edition):
Iagupov, Ilia. “Numerical design of meta-materials for photovoltaic applications : Design numérique de métamatériaux pour des applications photovoltaïques.” 2018. Doctoral Dissertation, Université Paris-Saclay (ComUE). Accessed March 29, 2020.
http://www.theses.fr/2018SACLX117.
MLA Handbook (7th Edition):
Iagupov, Ilia. “Numerical design of meta-materials for photovoltaic applications : Design numérique de métamatériaux pour des applications photovoltaïques.” 2018. Web. 29 Mar 2020.
Vancouver:
Iagupov I. Numerical design of meta-materials for photovoltaic applications : Design numérique de métamatériaux pour des applications photovoltaïques. [Internet] [Doctoral dissertation]. Université Paris-Saclay (ComUE); 2018. [cited 2020 Mar 29].
Available from: http://www.theses.fr/2018SACLX117.
Council of Science Editors:
Iagupov I. Numerical design of meta-materials for photovoltaic applications : Design numérique de métamatériaux pour des applications photovoltaïques. [Doctoral Dissertation]. Université Paris-Saclay (ComUE); 2018. Available from: http://www.theses.fr/2018SACLX117
17.
Chauvin, Sophie.
Cobaltates in the high-doping regime : Insights from first-principles calculations and extended dynamical mean-field theory : Etude des cobaltates fortement dopés par calculs premiers : Principes et théorie du champ moyen dynamique étendue.
Degree: Docteur es, Physique, 2016, Université Paris-Saclay (ComUE)
URL: http://www.theses.fr/2016SACLX110
► Comme de nombreux autres oxydes de métaux de transition lamellaires, les cobaltates dopés au sodium, NaxCoO2, présentent un riche diagramme de phase. Les nombreuses instabilités…
(more)
▼ Comme de nombreux autres oxydes de métaux de transition lamellaires, les cobaltates dopés au sodium, NaxCoO2, présentent un riche diagramme de phase. Les nombreuses instabilités (magnétiques, de charge) qui les caractérisent seraient notamment le fruit des corrélations électroniques. Dans cette thèse, nous nous intéressons au cas fortement dopé x=2/3 (proche de la limite de l'isolant de bande). Expérimentalement, ce composé est sujet à une disproportion de charge locale sur les atomes de cobalt, ce qui en fait un terrain d'étude privilégié pour le calcul des fonctions de corrélation de charge. Le traitement théorique de ce système est difficile a bien des égards. D'abord, la corrélation électronique demande de recourir à des approximations avancées. Ensuite, le système est sensible aux détails microscopiques, tels que transcrits dans la structure électronique réelle. Dans cette thèse, nous abordons ces deux aspects, à travers un approche sur modèle et une approche
ab initio.Nous examinons d'abord l'effet des corrélations au niveau d'un modèle sur réseau triangulaire, pertinent pour les cobaltates. La compétition entre les interactions de Coulomb locale et non-locale sur un modèle de Hubbard étendu donne lieu à des fluctuations de charge, que nous traitons grâce à la théorie du champ moyen dynamique étendue. Nous dressons le diagramme de phase de notre modèle en fonction des interactions locales et non-locales. Celui-ci présente une transition du second ordre entre un état métallique homogène et une phase ordonnée de charge. Nous calculons les observables à une et deux particules dans la phase homogène, et nous déterminons l'effet des corrélations sur ces deux types d'observables. Nous interprétons ces résultats comme des conséquences du fort dopage. Nous identifions une région du diagramme de phase où la partie statique de l'interaction de Coulomb écrantée devient négative. Enfin, nous montrons comment incorporer un terme de Fock non-local à ces calculs, et nous détaillons son effet sur le diagramme de phase et sur les observables physiques.En complément de notre approche sur modèle, nous étudions les détails microscopiques du matériau réel grâce à la théorie de la fonctionnelle de la densité. Nous analysons le rôle de l'hybridation avec l’oxygène et des processus de saut électronique sur la structure de bandes pour les plans de cobalt-oxygène. Nous clarifions l'effet de certains paramètres physiques, tels que le dopage au sodium, l'arrangement cristallin ou le magnétisme, sur la structure électronique. Puis nous calculons la susceptibilité de charge selon les premiers principes, selon des approximations suggérées par notre étude de modèle sur réseau.La comparaison entre les calculs sur modèle et
ab initio montre que ces approches se complètent l'une l'autre. D'une part, le modèle permet de dégager les approximations pertinentes pour le calcul des fonctions de corrélation de charge. D'autre part, les calculs
ab initio et la compréhension des processus microscopiques sont le préalable à la construction d'un modèle…
Advisors/Committee Members: Biermann, Silke (thesis director).
Subjects/Keywords: Corrélations; Cobaltates; Ab initio; Correlations; Cobaltates; Ab initio
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APA (6th Edition):
Chauvin, S. (2016). Cobaltates in the high-doping regime : Insights from first-principles calculations and extended dynamical mean-field theory : Etude des cobaltates fortement dopés par calculs premiers : Principes et théorie du champ moyen dynamique étendue. (Doctoral Dissertation). Université Paris-Saclay (ComUE). Retrieved from http://www.theses.fr/2016SACLX110
Chicago Manual of Style (16th Edition):
Chauvin, Sophie. “Cobaltates in the high-doping regime : Insights from first-principles calculations and extended dynamical mean-field theory : Etude des cobaltates fortement dopés par calculs premiers : Principes et théorie du champ moyen dynamique étendue.” 2016. Doctoral Dissertation, Université Paris-Saclay (ComUE). Accessed March 29, 2020.
http://www.theses.fr/2016SACLX110.
MLA Handbook (7th Edition):
Chauvin, Sophie. “Cobaltates in the high-doping regime : Insights from first-principles calculations and extended dynamical mean-field theory : Etude des cobaltates fortement dopés par calculs premiers : Principes et théorie du champ moyen dynamique étendue.” 2016. Web. 29 Mar 2020.
Vancouver:
Chauvin S. Cobaltates in the high-doping regime : Insights from first-principles calculations and extended dynamical mean-field theory : Etude des cobaltates fortement dopés par calculs premiers : Principes et théorie du champ moyen dynamique étendue. [Internet] [Doctoral dissertation]. Université Paris-Saclay (ComUE); 2016. [cited 2020 Mar 29].
Available from: http://www.theses.fr/2016SACLX110.
Council of Science Editors:
Chauvin S. Cobaltates in the high-doping regime : Insights from first-principles calculations and extended dynamical mean-field theory : Etude des cobaltates fortement dopés par calculs premiers : Principes et théorie du champ moyen dynamique étendue. [Doctoral Dissertation]. Université Paris-Saclay (ComUE); 2016. Available from: http://www.theses.fr/2016SACLX110
University of Georgia
18.
Sari, Levent.
Applications of the coupled-cluster theory on the novel H, Si, C, and Ge containing small molecules : effects of scalar relativity.
Degree: PhD, Chemistry, 2003, University of Georgia
URL: http://purl.galileo.usg.edu/uga_etd/sari_levent_200305_phd
► The highly correlated ab initio coupled-cluster theories have been employed on the ground and rst excited electronic states of the HCSi and HCGe tri-atomic molecules,…
(more)
▼ The highly correlated
ab initio coupled-cluster theories have been employed on
the ground and rst excited electronic states of the HCSi and HCGe tri-atomic
molecules, and on the ground electronic states of the GeC2, Si2H3, and Si2H4. The
main reason for the choice of these molecules is that very little or even nothing is
known about the structure, energetic, and other rst and second order molecular
properties. Also, these molecules are of interest because of their potential applications in semiconductors and optoelectronics, in surface growth processes, and their possible existence in the circumstellar atmospheres of evolved carbon stars. Large basis sets (e.g. TZ3P(2f,2d)+2diff and cc-pVQZ) have been employed in conjunction with the very sophisticated quantum mechanical methods such as CCSD(T),
CCSD(2), and CCSDT. Equation of motion coupled cluster theories were employed in order to determine some excited state properties, which cannot be determined using standard quantum mechanical methods due to possible variational collapses. Challenging problems such as characterization of the Renner-Teller splitting in the
ground ~X 2 states of HCSi and HCGe, determination of the true ground state equilibrium geometry for the elusive GeC2, and searching the unanticipated mono- and
di-bridged isomers of the Si2H3 and Si2H4 molecules have been focused. Investigation
of the e ects of the scalar relativistic corrections on some molecular properties as
well as on the Renner-Teller splitting has been another focus of interest throughout
the study. In some cases, corrections due to zero-point vibrational energies (ZPVE)
and core-valence interactions have been determined in order to predict reliable spectroscopic constants. The theoretical predictions for the HCSi and HCGe tri-atomic
molecules were compared with the few existent experimental and theoretical works
in literature. It has been observed that coupled cluster theory in conjunction with
large basis sets is able to predict bond distances within 0.1 and energetic properties within 1 kcal/mol accuracy. Inclusion of the scalar relativistic corrections even produced better estimates. The equilibrium geometry for the GeC2 molecule in its ground state is predicted to be L-Shaped rather than T-shaped as in the case of SiC2. For the structural predictions on the Si2H3 and Si2H4 molecules, collaboration with the Harvard experimentalists showed excellent agreements.
Advisors/Committee Members: Henry F. Schaefer.
Subjects/Keywords: Ab initio methods
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APA (6th Edition):
Sari, L. (2003). Applications of the coupled-cluster theory on the novel H, Si, C, and Ge containing small molecules : effects of scalar relativity. (Doctoral Dissertation). University of Georgia. Retrieved from http://purl.galileo.usg.edu/uga_etd/sari_levent_200305_phd
Chicago Manual of Style (16th Edition):
Sari, Levent. “Applications of the coupled-cluster theory on the novel H, Si, C, and Ge containing small molecules : effects of scalar relativity.” 2003. Doctoral Dissertation, University of Georgia. Accessed March 29, 2020.
http://purl.galileo.usg.edu/uga_etd/sari_levent_200305_phd.
MLA Handbook (7th Edition):
Sari, Levent. “Applications of the coupled-cluster theory on the novel H, Si, C, and Ge containing small molecules : effects of scalar relativity.” 2003. Web. 29 Mar 2020.
Vancouver:
Sari L. Applications of the coupled-cluster theory on the novel H, Si, C, and Ge containing small molecules : effects of scalar relativity. [Internet] [Doctoral dissertation]. University of Georgia; 2003. [cited 2020 Mar 29].
Available from: http://purl.galileo.usg.edu/uga_etd/sari_levent_200305_phd.
Council of Science Editors:
Sari L. Applications of the coupled-cluster theory on the novel H, Si, C, and Ge containing small molecules : effects of scalar relativity. [Doctoral Dissertation]. University of Georgia; 2003. Available from: http://purl.galileo.usg.edu/uga_etd/sari_levent_200305_phd
University of Georgia
19.
Yan, Ge.
Applications of modern quantum mechanical theories: from propargyl and hydroxyformyl radicals to adamantane.
Degree: PhD, Chemistry, 2005, University of Georgia
URL: http://purl.galileo.usg.edu/uga_etd/yan_ge_200508_phd
► Modern quantum mechanical theories, including high-level ab initio methods and density functional theory, have been applied to a variety of molecular systems. The first work…
(more)
▼ Modern quantum mechanical theories, including high-level
ab initio methods and density functional theory, have been applied to a variety of molecular systems. The first work performs a comprehensive anharmonic vibrational analysis of propargyl radical. A highly-accurate quartic force field was constructed with coupled-cluster including singles and doubles and perturbatively applied triple excitations [CCSD(T)] using the aug’-cc-pVTZ basis set, complemented with a quadratic force field extrapolated to the complete basis set limit using cc-pVXZ (X=T, Q, 5) basis sets. Fundamental vibrational frequencies were computed with the complete quartic force field based on vibrational perturbation theory. In the second work, accurate electron affinities and ionization potentials of trans- and cis-hydroxyformyl radicals were determined via systematic
ab initio investigations. State-of-the-art
ab initio electronic structure theories combined with aug-cc-p(C)VXZ (X=2-6) basis sets were utilized to extrapolate to the complete basis set full configuration interaction limit via the focal point analysis method. Core-correlation effects, special relativity, zero-point vibrational energy, and diagonal Born-Oppenheimer corrections were explicitly incorporated in the results to -1provide accuracy to the level of 0.1 kcal mol. The last work examines optimal structures, energetics, and harmonic vibrational frequencies of adamantane and a variety of its derivatives using four different density functional methods and the DZP++ basis set. Electronic affinities, ionization potentials and other properties have been predicted.
Advisors/Committee Members: Henry F. Schaefer, III.
Subjects/Keywords: ab initio Method
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APA (6th Edition):
Yan, G. (2005). Applications of modern quantum mechanical theories: from propargyl and hydroxyformyl radicals to adamantane. (Doctoral Dissertation). University of Georgia. Retrieved from http://purl.galileo.usg.edu/uga_etd/yan_ge_200508_phd
Chicago Manual of Style (16th Edition):
Yan, Ge. “Applications of modern quantum mechanical theories: from propargyl and hydroxyformyl radicals to adamantane.” 2005. Doctoral Dissertation, University of Georgia. Accessed March 29, 2020.
http://purl.galileo.usg.edu/uga_etd/yan_ge_200508_phd.
MLA Handbook (7th Edition):
Yan, Ge. “Applications of modern quantum mechanical theories: from propargyl and hydroxyformyl radicals to adamantane.” 2005. Web. 29 Mar 2020.
Vancouver:
Yan G. Applications of modern quantum mechanical theories: from propargyl and hydroxyformyl radicals to adamantane. [Internet] [Doctoral dissertation]. University of Georgia; 2005. [cited 2020 Mar 29].
Available from: http://purl.galileo.usg.edu/uga_etd/yan_ge_200508_phd.
Council of Science Editors:
Yan G. Applications of modern quantum mechanical theories: from propargyl and hydroxyformyl radicals to adamantane. [Doctoral Dissertation]. University of Georgia; 2005. Available from: http://purl.galileo.usg.edu/uga_etd/yan_ge_200508_phd
University of Georgia
20.
Wang, Suyun.
Ab initio quantum mechanical applications to molecular systems from triatomics to nucleic acid bases.
Degree: PhD, Chemistry, 2006, University of Georgia
URL: http://purl.galileo.usg.edu/uga_etd/wang_suyun_200605_phd
► Ab initio quantum mechanical computational techniques have been applied to questions in various molecular systems from triatomics to nucleic acid (NA) bases. For triatomic copper…
(more)
▼ Ab initio quantum mechanical computational techniques have been applied to questions in various molecular systems from triatomics to nucleic acid (NA) bases. For triatomic copper hydroxide (CuOH), a range of
ab initio methods have been employed to investigate the ground and two lowest-lying singlet excited electronic states. The 11optimized geometrical parameters for the A' and 1 A" states agree fairly well with 1available experimental values. However, the 2 A' structure is in poor agreement with experiment. The predicted adiabatic excitation energies are also inconsistent with 11experiment for the 2 A' and 1 A" states. All theoretical methods show lower adiabatic 1-1excitation energies for the 1 A" state (53.1 kcal mol) than those for the corresponding 1-112 A' state (57.6 kcal mol), suggesting that the 1 A" state might be the first singlet 1excited state while the 2 A' state might be the second singlet excited state. Extensive
ab initio methods have been used to study the triatomic PCN / PNC species and the transition state of the exothermic PNC ’ PCN reaction. Both PCN and 3-3-PNC are linear with £ ground states, and linear PNC ( £) is predicted to lie 13.5 -1kcal mol [with zero-point vibrational energy (ZPVE) correction] above linear PCN ~X~X 3-3( £). The isomerization transition state is found to be cyclic PCN ( A3) with angles ¸e (PCN) = 82.2¡, ¸e (CNP) = 63.1¡, and ¸e (NPC) = 34.7¡. The isomerization -13-barrier is predicted to be 35.7 kcal mol relative to linear PCN ( £). With respect to the NA bases, the
ab initio Hartree-Fock (HF) and second-order M¿ller-Plesset perturbation (MP2) methods have been applied to analyze the nonplanarity of the NA base amino group. New benchmark predictions have been obtained at the cc-pCVQZ and aug-cc-pVQZ MP2 levels of theory for adenine, guanine, cytosine, thymine, and uracil. Three out of the five NA bases, namely adenine, guanine, and cytosine, are intrinsically nonplanar due to the existence of pyramidal amino groups. Guanine is much more nonplanar than adenine and cytosine. The predicted classical barriers to planarization are 0.020 (adenine), 0.742 (guanine), and 0.032 (cytosine) kcal -1mol.
Advisors/Committee Members: Henry F. Schaefer.
Subjects/Keywords: Ab Initio Method
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APA (6th Edition):
Wang, S. (2006). Ab initio quantum mechanical applications to molecular systems from triatomics to nucleic acid bases. (Doctoral Dissertation). University of Georgia. Retrieved from http://purl.galileo.usg.edu/uga_etd/wang_suyun_200605_phd
Chicago Manual of Style (16th Edition):
Wang, Suyun. “Ab initio quantum mechanical applications to molecular systems from triatomics to nucleic acid bases.” 2006. Doctoral Dissertation, University of Georgia. Accessed March 29, 2020.
http://purl.galileo.usg.edu/uga_etd/wang_suyun_200605_phd.
MLA Handbook (7th Edition):
Wang, Suyun. “Ab initio quantum mechanical applications to molecular systems from triatomics to nucleic acid bases.” 2006. Web. 29 Mar 2020.
Vancouver:
Wang S. Ab initio quantum mechanical applications to molecular systems from triatomics to nucleic acid bases. [Internet] [Doctoral dissertation]. University of Georgia; 2006. [cited 2020 Mar 29].
Available from: http://purl.galileo.usg.edu/uga_etd/wang_suyun_200605_phd.
Council of Science Editors:
Wang S. Ab initio quantum mechanical applications to molecular systems from triatomics to nucleic acid bases. [Doctoral Dissertation]. University of Georgia; 2006. Available from: http://purl.galileo.usg.edu/uga_etd/wang_suyun_200605_phd
Addis Ababa University
21.
GETASEW, MULUALEM.
AB–INITIO CALCULATIONS OF STRUCTURAL AND ELECTRONIC PROPERTIES OF A BeXZn1-XSe TERNARY ALLOY
.
Degree: 2013, Addis Ababa University
URL: http://etd.aau.edu.et/dspace/handle/123456789/760
► We have used the ab-initio SIESTA code within the framework of DFT, LDA method to calculate the structural and electronic properties of BexZn1-xSe alloy for…
(more)
▼ We have used the
ab-
initio SIESTA code within the framework of DFT, LDA method
to calculate the structural and electronic properties of BexZn1-xSe alloy for different
compositions x = 0.0, 0.33, 0.66, and 1.0. The system is modelled in various possible
configurations using a large 54-atom supercell. It is noteworthy to mention that the
determination of structural and electronic properties of a BexZn1-xSe ternary alloy at x
= 0.33 and 0.66 have not been reported earlier to the best of our knowledge. We
analyze composition effect on lattice constants, bulk modulus, pressure derivative,
bandgap, and density of states. Deviations of the lattice constant from Vegard’s law
and the bulk modulus from linear concentration dependence are observed. It was
deduced that increasing the Be composition in the alloy increases the hardness of the
materials. In addition, the calculated band structures showed that the bandgap
undergoes a direct-to-indirect transition at the composition of 0.84. The bandgap is
found to vary non-linearly with Be composition. Using the approach of Bernard and
Zunger, the microscopic origins of bandgap bowing is also explained. It is concluded
that the energy bandgap bowing is primarily due to volume deformation effect.
Furthermore, the structural phase transformations of ZnSe under high pressure are
also studied by similar method. It is found that ZnSe undergoes a first-order phase
transition from the zinc blende structure to the rock salt structure at approximately
13.75 GPa. The ground state properties of the phases of ZnSe are also calculated. Our
results are in good agreements with experimental observations.
Advisors/Committee Members: Prof. Javed Mazher (advisor).
Subjects/Keywords: ab-initio SIESTA code;
DFT;
LDA
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APA (6th Edition):
GETASEW, M. (2013). AB–INITIO CALCULATIONS OF STRUCTURAL AND ELECTRONIC PROPERTIES OF A BeXZn1-XSe TERNARY ALLOY
. (Thesis). Addis Ababa University. Retrieved from http://etd.aau.edu.et/dspace/handle/123456789/760
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
GETASEW, MULUALEM. “AB–INITIO CALCULATIONS OF STRUCTURAL AND ELECTRONIC PROPERTIES OF A BeXZn1-XSe TERNARY ALLOY
.” 2013. Thesis, Addis Ababa University. Accessed March 29, 2020.
http://etd.aau.edu.et/dspace/handle/123456789/760.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
GETASEW, MULUALEM. “AB–INITIO CALCULATIONS OF STRUCTURAL AND ELECTRONIC PROPERTIES OF A BeXZn1-XSe TERNARY ALLOY
.” 2013. Web. 29 Mar 2020.
Vancouver:
GETASEW M. AB–INITIO CALCULATIONS OF STRUCTURAL AND ELECTRONIC PROPERTIES OF A BeXZn1-XSe TERNARY ALLOY
. [Internet] [Thesis]. Addis Ababa University; 2013. [cited 2020 Mar 29].
Available from: http://etd.aau.edu.et/dspace/handle/123456789/760.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
GETASEW M. AB–INITIO CALCULATIONS OF STRUCTURAL AND ELECTRONIC PROPERTIES OF A BeXZn1-XSe TERNARY ALLOY
. [Thesis]. Addis Ababa University; 2013. Available from: http://etd.aau.edu.et/dspace/handle/123456789/760
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Ruhr Universität Bochum
22.
Bialon, Arthur.
The iron-boron system : ordered structures and point
defects.
Degree: 2013, Ruhr Universität Bochum
URL: http://nbn-resolving.de/urn/resolver.pl?urn=urn:nbn:de:hbz:294-38641
► In der vorliegenden Dissertation wurde die Bildung von binären und ternären Phasen aus Übergangsmetallen und p-Block- Elementen mit Hilfe von Strukturkarten und das Eisen-Bor-System im…
(more)
▼ In der vorliegenden Dissertation wurde die Bildung
von binären und ternären Phasen aus Übergangsmetallen und p-Block-
Elementen mit Hilfe von Strukturkarten und das Eisen-Bor-System im
Speziellen mit Dichtefunktionaltheorie in Hinblick auf
Phasenbildung und Verhalten von Bor-Defekten in Eisen untersucht.
Die verschiedenen Kristallstrukturen konnten mit Hilfe von
Ordnungsparametern, basierend auf einer Polyeder-Analyse, in klar
abgegrenzte Bereiche in 2D Strukturkarten platziert werden. Die
Untersuchung des Eisen-Bor-System mit Dichtefunktionaltheorie im
Hinblick auf Phasenbildung weist auf neue, bisher unbekannte Phasen
bei hohen Bor-Anteilen hin. Das Verhalten von Bor-Defekten in
bcc-Eisen hinsichtlich Mobilität, elastischen Konstanten und
Wechselwirkungen mit anderen Punktdefekten ist stark von der
Position von Bor im Eisen abhängig: substitutionell ähnelt es einer
Fehlstelle und bindet andere Punktdefekte, interstitiell ähnelt es
Kohlenstoff/Stickstoff und wirkt abstoßend.
Advisors/Committee Members: Physik und Astronomie.
Subjects/Keywords: Dichtefunktionalformalismus; Ab-initio-Rechnung;
Kristallstruktur; Kristallstrukturanalyse;
Gitterbaufehler
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APA (6th Edition):
Bialon, A. (2013). The iron-boron system : ordered structures and point
defects. (Thesis). Ruhr Universität Bochum. Retrieved from http://nbn-resolving.de/urn/resolver.pl?urn=urn:nbn:de:hbz:294-38641
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Bialon, Arthur. “The iron-boron system : ordered structures and point
defects.” 2013. Thesis, Ruhr Universität Bochum. Accessed March 29, 2020.
http://nbn-resolving.de/urn/resolver.pl?urn=urn:nbn:de:hbz:294-38641.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Bialon, Arthur. “The iron-boron system : ordered structures and point
defects.” 2013. Web. 29 Mar 2020.
Vancouver:
Bialon A. The iron-boron system : ordered structures and point
defects. [Internet] [Thesis]. Ruhr Universität Bochum; 2013. [cited 2020 Mar 29].
Available from: http://nbn-resolving.de/urn/resolver.pl?urn=urn:nbn:de:hbz:294-38641.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Bialon A. The iron-boron system : ordered structures and point
defects. [Thesis]. Ruhr Universität Bochum; 2013. Available from: http://nbn-resolving.de/urn/resolver.pl?urn=urn:nbn:de:hbz:294-38641
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Louisiana State University
23.
McKenzie, Matthew Edward.
Computational studies on fatty acid synthesis: from mechanisms to drug design.
Degree: PhD, Chemistry, 2009, Louisiana State University
URL: etd-06112009-104535
;
https://digitalcommons.lsu.edu/gradschool_dissertations/1998
► The first committed steps of the Fatty Acid synthesis pathway involves the de/carboxylation reactions of biotin. By understanding this step, potential novel antimicrobial agents could…
(more)
▼ The first committed steps of the Fatty Acid synthesis pathway involves the de/carboxylation reactions of biotin. By understanding this step, potential novel antimicrobial agents could be discovered. The current tools of drug discovery can only help the research in finding and modifying potential hits. Finding a lead candidate from these programs are often equated to finding a needle in a haystack, which is due to the many assumptions used in molecular docking. The fundamental reaction kinetics can not be described by these techniques and a detailed study of the decarboxylation reaction is investigated using ab initio molecular dynamics. In this particular study, Car-Parrinello molecular dynamics is used and how the biotin model is protonated was found to play an important role in its reaction barrier. Although stable in low acidic solutions, a crucial nitrogen protonation is shown to have the lowest free energy barrier which could play a pivotal role in the enzymatic mechanism. The molecular docking knowledge of potential ligand inhibitors via a low level modeling technique connected to high level quantum mechanical reaction modeling provides a synergistic route in the search for inhibitors.
Subjects/Keywords: molecular dynamics; drug design; ab initio; reactions
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APA (6th Edition):
McKenzie, M. E. (2009). Computational studies on fatty acid synthesis: from mechanisms to drug design. (Doctoral Dissertation). Louisiana State University. Retrieved from etd-06112009-104535 ; https://digitalcommons.lsu.edu/gradschool_dissertations/1998
Chicago Manual of Style (16th Edition):
McKenzie, Matthew Edward. “Computational studies on fatty acid synthesis: from mechanisms to drug design.” 2009. Doctoral Dissertation, Louisiana State University. Accessed March 29, 2020.
etd-06112009-104535 ; https://digitalcommons.lsu.edu/gradschool_dissertations/1998.
MLA Handbook (7th Edition):
McKenzie, Matthew Edward. “Computational studies on fatty acid synthesis: from mechanisms to drug design.” 2009. Web. 29 Mar 2020.
Vancouver:
McKenzie ME. Computational studies on fatty acid synthesis: from mechanisms to drug design. [Internet] [Doctoral dissertation]. Louisiana State University; 2009. [cited 2020 Mar 29].
Available from: etd-06112009-104535 ; https://digitalcommons.lsu.edu/gradschool_dissertations/1998.
Council of Science Editors:
McKenzie ME. Computational studies on fatty acid synthesis: from mechanisms to drug design. [Doctoral Dissertation]. Louisiana State University; 2009. Available from: etd-06112009-104535 ; https://digitalcommons.lsu.edu/gradschool_dissertations/1998
University of Tennessee – Knoxville
24.
Li, Congyi.
Characterization of Radiation Effects and <i>Ab Initio</i> Modeling of Defects in a High Entropy Alloy for Nuclear Power Application.
Degree: 2018, University of Tennessee – Knoxville
URL: https://trace.tennessee.edu/utk_graddiss/5005
► A novel Co-free NiFeMnCr HEA was synthesized for both ion and neutron irradiation studies. 3 and 5.8MeV heavy ion irradiations were conducted at room temperature…
(more)
▼ A novel Co-free NiFeMnCr HEA was synthesized for both ion and neutron irradiation studies. 3 and 5.8MeV heavy ion irradiations were conducted at room temperature and 400 – 700 °C from 0.03 to 10dpa. Post-irradiation examination included x-ray diffraction, nanoindentation hardness and transmission electron microscopy. The HEA exhibited quantitatively superior radiation resistance than conventional alloys, including suppressed void swelling and solute segregation.Neutron irradiation was conducted at 60 °C from 0.1 to 1dpa. Microhardness, electrical resistivity and positron annihilation spectroscopy measurements were performed at room temperature before and after isochronal annealing up to 700°C on the neutron-irradiated samples. The HEA retains fundamental stability after neutron irradiation. Compared with metals and conventional alloys, the HEA showed similar annealing trend of hardness and vacancy-type of defects. On the other hand, this HEA showed unique annealing trend of electrical resistivity. The large radiation induced resistivity increase (>10 μΩ∙cm) did not recover up to 700 °C, suggesting short range ordering phenomena may be critical in radiation effects of HEA.In parallel, ab initio modeling was conducted to establish a solid foundation for multiscale modeling of HEA as well as to reveal unique defect physics of HEA. Magnetic structure was computed based on coherent potential. Vacancy energetics were computed by Vienna Ab initio Simulation Package (VASP). Modeling results shows that it is reasonable to neglect magnetic interactions. The statistical distribution of vacancy formation energy is weakly dependent upon either the chemical species of the atom site associated with the vacancy, or local chemical environment. The calculated migration energy values show a large spread, varying between 0.55 to 1.68eV, although the mean value is comparable to that of conventional austenitic alloys. Finally, positron lifetime of bulk HEA, mono-vacancy and small vacancy clusters were computed by a finite element based ab initio package to facilitate the interpretation of experimental results from positron annihilation spectroscopy.
Subjects/Keywords: Radiation Effect; Alloy; Ab initio Modeling
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APA (6th Edition):
Li, C. (2018). Characterization of Radiation Effects and <i>Ab Initio</i> Modeling of Defects in a High Entropy Alloy for Nuclear Power Application. (Doctoral Dissertation). University of Tennessee – Knoxville. Retrieved from https://trace.tennessee.edu/utk_graddiss/5005
Chicago Manual of Style (16th Edition):
Li, Congyi. “Characterization of Radiation Effects and <i>Ab Initio</i> Modeling of Defects in a High Entropy Alloy for Nuclear Power Application.” 2018. Doctoral Dissertation, University of Tennessee – Knoxville. Accessed March 29, 2020.
https://trace.tennessee.edu/utk_graddiss/5005.
MLA Handbook (7th Edition):
Li, Congyi. “Characterization of Radiation Effects and <i>Ab Initio</i> Modeling of Defects in a High Entropy Alloy for Nuclear Power Application.” 2018. Web. 29 Mar 2020.
Vancouver:
Li C. Characterization of Radiation Effects and <i>Ab Initio</i> Modeling of Defects in a High Entropy Alloy for Nuclear Power Application. [Internet] [Doctoral dissertation]. University of Tennessee – Knoxville; 2018. [cited 2020 Mar 29].
Available from: https://trace.tennessee.edu/utk_graddiss/5005.
Council of Science Editors:
Li C. Characterization of Radiation Effects and <i>Ab Initio</i> Modeling of Defects in a High Entropy Alloy for Nuclear Power Application. [Doctoral Dissertation]. University of Tennessee – Knoxville; 2018. Available from: https://trace.tennessee.edu/utk_graddiss/5005
25.
Azarias, Cloé.
Modeling azacalixphyrin macrocycles : Modélisation de macrocycles de la famille des azacalixphyrines.
Degree: Docteur es, Chimie théorique, physique, analytique, 2018, Nantes
URL: http://www.theses.fr/2018NANT4021
► Cette thèse porte sur la modélisation des propriétés structurales, aromatiques et spectroscopiques d'une nouvelle classe de macrocycles alternatifs aux porphyrines, les azacalixphyrines (ACPs). Ces macrocycles…
(more)
▼ Cette thèse porte sur la modélisation des propriétés structurales, aromatiques et spectroscopiques d'une nouvelle classe de macrocycles alternatifs aux porphyrines, les azacalixphyrines (ACPs). Ces macrocycles conjugués, synthétisés et caractérisés pour la première fois en 2010 par le groupe d’Olivier Siri à Marseille, ont montré des propriétés exceptionnelles (structure, absorption, tautomérie, et complexation). Cette thèse vise à proposer de nouveaux dérivés aux propriétés améliorées, notamment en ce qui concerne leur absorption, en utilisant les outils offerts par la chimie théorique. Parmi toutes les approches ab initio permettant de modéliser les ACPs, la théorie fonctionnelle de la densité (DFT) et sa forme dépendante du temps (TDDFT) ont été principalement appliquées, bien que des calculs utilisant des méthodes alternatives aient également été effectués, notamment à l'aide du formalisme Bethe-Salpeter (BSE/evGW) dans le cadre d'une collaboration avec l'équipe du Dr. Xavier Blase à Grenoble. Trois stratégies chimiques ont été évaluées: (i) l’extension de la délocalisation des électrons en fusionnant plusieurs unités ACP; (ii) la substitution de l’ACP via l'addition de groupes électroactifs; et (iii) le couplage du macrocycle avec un fluorophore présentant une absorption complémentaire afin d'absorber la lumière sur une plus grande gamme du spectre et déclencher des processus de transfert d'énergie entre les sous-unités. Les deux premiers axes ont été réalisés en collaboration avec l'équipe d’Olivier Siri alors que le dernier est le fruit d'une collaboration avec le groupe de Benedetta Mennucci à Pise.
This thesis focuses on the modeling of the structural, aromatic, and spectroscopic properties of a new class of macrocycles alternative to porphyrins, i.e., azacalixphyrins (ACPs). These conjugated macrocycles have first been synthesized and characterized in 2010 by Siri’s group in Marseille and revealed exceptional features (structure, NIR absorption, tautomerism, and complexation). This thesis aimed at using ab initio methods to propose new ACP derivatives with improved properties with a focus on their absorption. The Density Functional Theory (DFT) and Time- Dependent DFT (TD-DFT) methods have been predominantly applied, although alternative wavefunction-based theories [the second-order Coupled-Cluster, CC2, and the Algebraic Diagrammatic Construction, ADC(2)] as well as the Bethe-Salpeter formalism, BSE/evGW, have also been used. Three major directions to develop new ACP derivatives have been investigated: (i) the extension of the ACP -conjugation path by fusing several ACP moieties leading to multimers; (ii) chemical modifications of the ACP unit by addition of electroactive groups; and (iii) coupling of the ACP moiety with a fluorophore presenting a complementary absorption spectrum in order to improve the light harvesting and to trigger excitation energy transfer processes. The two former axes have been investigated in collaboration with Siri’s team whereas the latter has arisen from a collaboration…
Advisors/Committee Members: Jacquemin, Denis (thesis director), Lasorne, Benjamin (thesis director).
Subjects/Keywords: Calculs ab initio; Azacalixphyrine; TD-DFT; DFT
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APA (6th Edition):
Azarias, C. (2018). Modeling azacalixphyrin macrocycles : Modélisation de macrocycles de la famille des azacalixphyrines. (Doctoral Dissertation). Nantes. Retrieved from http://www.theses.fr/2018NANT4021
Chicago Manual of Style (16th Edition):
Azarias, Cloé. “Modeling azacalixphyrin macrocycles : Modélisation de macrocycles de la famille des azacalixphyrines.” 2018. Doctoral Dissertation, Nantes. Accessed March 29, 2020.
http://www.theses.fr/2018NANT4021.
MLA Handbook (7th Edition):
Azarias, Cloé. “Modeling azacalixphyrin macrocycles : Modélisation de macrocycles de la famille des azacalixphyrines.” 2018. Web. 29 Mar 2020.
Vancouver:
Azarias C. Modeling azacalixphyrin macrocycles : Modélisation de macrocycles de la famille des azacalixphyrines. [Internet] [Doctoral dissertation]. Nantes; 2018. [cited 2020 Mar 29].
Available from: http://www.theses.fr/2018NANT4021.
Council of Science Editors:
Azarias C. Modeling azacalixphyrin macrocycles : Modélisation de macrocycles de la famille des azacalixphyrines. [Doctoral Dissertation]. Nantes; 2018. Available from: http://www.theses.fr/2018NANT4021
University of Illinois – Chicago
26.
Buurma, Christopher F.
Application of ab-initio Methods to Grain Boundaries and Point Defects for Poly-CdTe Solar Cells.
Degree: 2015, University of Illinois – Chicago
URL: http://hdl.handle.net/10027/19477
► CdTe is a material well-suited to solar cell applications due to its 1.5 eV direct bandgap and high optical absorption. To meet energy demands, CdTe…
(more)
▼ CdTe is a material well-suited to solar cell applications due to its 1.5 eV direct bandgap and high optical absorption. To meet energy demands, CdTe solar cells must be produced at a low-cost and with high throughput which often demands the use of non-ideal polycrystalline CdTe. As a result of careful process control, current thin-film poly-CdTe cells have been shown to be somewhat defect tolerant with proven industry success.
Yet despite this success poly-CdTe cells are still far from their predicted Shockley-Queisser theoretical limits. The next generation cells must demonstrate higher open-circuit voltages, fill factors, and longer minority carrier lifetimes. Playing a major role in doping, defect migration, carrier recombination, and current transport are 2D extended defects both within grains and between grains as grain boundaries (GBs). A further understanding of these defects is needed which exhibit either high symmetry such as the CSL structures or those mixed or random GBs with low symmetry. Their corresponding formation and electronic behavior will be needed to develop methods to mitigate their effects and instead promote higher doping with less minority carrier recombination.
Predictions and guidance on electronic and thermodynamic properties can be obtained from model atomic structures within the framework of
ab-
initio density-functional theory. Bulk point defect formation energies were determined for comparison to calculations of point defects along GB structures. Model atomic structures of GBs can also be created rapidly and over a wide parameter space using the Grain Boundary Genie code developed for this project. Commonly observed low-angle and special coincident grain boundaries structures were created and a subset relaxed to determine their local strain environment and interfacial energy with for comparison to STEM observations. Additionally, a series of random angle or ‘mixed’ grain boundaries were created and investigated corresponding to possible interfaces between grains that cannot be observed in STEM.
Advisors/Committee Members: Sivananthan, Sivalingam (advisor), Chan, Maria K. (committee member), Grein, Christoph (committee member), Klie, Robert (committee member), Metzger, Wyatt (committee member).
Subjects/Keywords: CdTe; Solar; ab-initio; Grain Boundary
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APA (6th Edition):
Buurma, C. F. (2015). Application of ab-initio Methods to Grain Boundaries and Point Defects for Poly-CdTe Solar Cells. (Thesis). University of Illinois – Chicago. Retrieved from http://hdl.handle.net/10027/19477
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Buurma, Christopher F. “Application of ab-initio Methods to Grain Boundaries and Point Defects for Poly-CdTe Solar Cells.” 2015. Thesis, University of Illinois – Chicago. Accessed March 29, 2020.
http://hdl.handle.net/10027/19477.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Buurma, Christopher F. “Application of ab-initio Methods to Grain Boundaries and Point Defects for Poly-CdTe Solar Cells.” 2015. Web. 29 Mar 2020.
Vancouver:
Buurma CF. Application of ab-initio Methods to Grain Boundaries and Point Defects for Poly-CdTe Solar Cells. [Internet] [Thesis]. University of Illinois – Chicago; 2015. [cited 2020 Mar 29].
Available from: http://hdl.handle.net/10027/19477.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Buurma CF. Application of ab-initio Methods to Grain Boundaries and Point Defects for Poly-CdTe Solar Cells. [Thesis]. University of Illinois – Chicago; 2015. Available from: http://hdl.handle.net/10027/19477
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Colorado School of Mines
27.
LaCount, Michael D.
Energy pooling upconversion in free space and optical cavities.
Degree: PhD, Physics, 2017, Colorado School of Mines
URL: http://hdl.handle.net/11124/170985
► The ability to efficiently convert the wavelength of light has value in a wide range of disciplines that include the fields of photovoltaics, plant growth,…
(more)
▼ The ability to efficiently convert the wavelength of light has value in a wide range of disciplines that include the fields of photovoltaics, plant growth, optics and medicine. The processes by which such transformations are carried out are known as upconversions and downconversions. There are several ways to up/down convert light, each with its own attributes, issues, and competing mechanisms. Most are associated with one-body or two-body processes. Three-body dynamics are also possible though, going by the names of quantum cutting (downconversion) and energy pooling (upconversion). These use virtual excited electronic states to mediate conversions as has been experimentally realized using lanthanide ions embedded in wide bandgap materials. The use of lanthanides to convert light is not ideal due to their relative scarcity, toxicity, and the limited range of light frequencies that can be absorbed and emitted. Organic molecules, on the other hand, are typically non-toxic, are made up of abundant elements, and can be designed with tailored spectral properties. At issue is whether or not they can be used to carry out efficient energy pooling, the central question to be answered in this thesis. The research presented here draws on a perturbative quantum electrodynamics framework previously established for generic energy pooling. It was used to develop a computational methodology for determining the rate of energy pooling and its competing processes. This, in turn, draws on a combination of time-dependent density functional theory, quantum electrodynamics, and perturbation theory to generate the requisite material property data. This computational model was applied to two test systems consisting of stilbene-fluorescein and hexabenzocoronene-oligothiophene. The stilbene-fluorescein system was found to have a maximum energy pooling rate efficiency (as compared to competing processes) of 17% and the hexabenzocoronene-oligothiophene system was found to have a maximum energy pooling rate efficiency of 99%. This demonstrates that the energy pooling rate can be made faster than its competing processes. Based on the results of this study, a set of design rules was developed to optimize the rate efficiency of energy pooling. Prior to this research, no attempt had been made to determine if energy pooling could be made to out-pace competing processes – i.e. whether or not a molecular system could be designed to utilize energy pooling as an efficient means of upconversion. This initial investigation was part of a larger effort involving a team of researchers at the University of Colorado, Boulder and at the National Renewable Energy Laboratory. After establishing our computational proof-of-concept, we collectively used the new design rules to select an improved system for energy pooling. This consisted of rhodamine 6G and stilbene-420. These molecules were fabricated into a thin film, and the maximum internal quantum yield was measured to be 36% under sufficiently high intensity light. To further increase the efficiency of…
Advisors/Committee Members: Lusk, Mark T. (advisor), Carr, Lincoln D. (committee member), Durfee, Charles G. (committee member), Sellinger, Alan (committee member).
Subjects/Keywords: Cavity; Perturbation; Upconversion; Kinetic; Ab initio; QED
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APA (6th Edition):
LaCount, M. D. (2017). Energy pooling upconversion in free space and optical cavities. (Doctoral Dissertation). Colorado School of Mines. Retrieved from http://hdl.handle.net/11124/170985
Chicago Manual of Style (16th Edition):
LaCount, Michael D. “Energy pooling upconversion in free space and optical cavities.” 2017. Doctoral Dissertation, Colorado School of Mines. Accessed March 29, 2020.
http://hdl.handle.net/11124/170985.
MLA Handbook (7th Edition):
LaCount, Michael D. “Energy pooling upconversion in free space and optical cavities.” 2017. Web. 29 Mar 2020.
Vancouver:
LaCount MD. Energy pooling upconversion in free space and optical cavities. [Internet] [Doctoral dissertation]. Colorado School of Mines; 2017. [cited 2020 Mar 29].
Available from: http://hdl.handle.net/11124/170985.
Council of Science Editors:
LaCount MD. Energy pooling upconversion in free space and optical cavities. [Doctoral Dissertation]. Colorado School of Mines; 2017. Available from: http://hdl.handle.net/11124/170985
Universidade Estadual de Campinas
28.
Amorim, Edgard Pacheco Moreira.
Propriedades mecânicas e eletrônicas de nanofios de cobre e ouro
.
Degree: 2010, Universidade Estadual de Campinas
URL: http://repositorio.unicamp.br/jspui/handle/REPOSIP/277683
► Resumo: A necessidade de ampliar a capacidade de processamento computacional produziu um intenso esforço científico e tecnológico para produzir circuitos eletrônicos cada vez menores. Recentemente,…
(more)
▼ Resumo: A necessidade de ampliar a capacidade de processamento computacional produziu um intenso esforço científico e tecnológico para produzir circuitos eletrônicos cada vez menores. Recentemente, resultados experimentais e teóricos estabeleceram que nanofios de cobre e ouro sob tensão evoluem para cadeias atômicas, o menor condutor possível. Neste trabalho, utilizando dinâmica molecular tight-binding observamos a evolução dinâmica de nanofios de cobre sob tensão nas direções cristalográficas [100], [110] e [111] elongando-os até a ruptura. As estruturas obtidas antes da ruptura foram usadas para iniciar os cálculos de primeiros-princípios baseado na teoria do funcional da densidade nas aproximações de densidade local e gradiente generalizado (LDA e GGA) até observamos novamente a ruptura. O nanofio elongado na direção [111] foi dopado com impurezas de H, B, C, N, O, S e N2 e elongado para verificarmos como as impurezas afetam suas propriedades estruturais e eletrônicas. Constatamos um efeito mecanoquímico devido a inserção de N e N2 que formam ligações p-d estáveis e muito fortes, causando o rearranjo das pontas adicionando mais átomos a cadeia atômica linear, sugerindo que nanofios unidimensionais maiores poderiam ser obtidos se produzidos em atmosferas nitrogenadas. Observamos as diferenças e similaridades na evolução dinâmica de nanofios de cobre e ouro elongados na direção [111]. Em ambos os metais, o primeiro rearranjo significativo ocorre devido a um átomo do interior do nanofio que vai para sua superfície. Objetivando compreender melhor este efeito, consideramos suas configurações ocas ou de camada única. Comparamos as forças calculadas suportadas pelos nanofios e mostramos que os nanofios de parede única podem suportar forças maiores antes do seu primeiro rearranjo estrutural em ambos os metais comparados aos nanofios originais. Investigamos também a dependência das forças máximas sustentadas pelos nanofios de parede única com respeito ao diâmetro. Nossos resultados sugerem que nanofios de cobre suportam mais tensão uniaxial do que os de ouro além de evoluir para cadeias atômicas lineares menores, indicando uma menor maleabilidade do cobre comparado ao ouro, como observado no sólido macroscópico. Experimentos mostraram que nanofios de ouro formados ao longo da direção [110] reconstroem sob tensão como estruturas helicoidais. Através de sua evolução dinâmica, nossos cálculos mostram que estes nanofios intrinsecamente tornam-se helicoidais devido aos planos (111) compactos que formam um ângulo com a direção de elongação mantendo o registro do seu arranjo angular inicial, além da tendência dos átomos do interior migrarem para sua superfície reconstruindo-a como {111} que é a superfície de mais baixa energia livre. Estes nanofios evoluem sob tensão formando cadeias atômicas lineares mais longas do que nanofios elongados em outras direções porque suas pontas são menos simétricas. Na configuração próxima a ruptura, estudamos a estrutura eletrônica de átomos de diferentes coordenações com cálculos
ab-
initio na…
Advisors/Committee Members: Silva, Edison Zacarias da, 1952- (advisor), Antonelli, Alex (committee member), Vitiello, Silvio Antonio Sachetto (committee member), Latge, Andrea Brito (committee member), Miranda, Caetano Rodrigues (committee member).
Subjects/Keywords: Nanofios;
Dinâmica molecular;
Ab initio;
Cobre;
Ouro
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APA (6th Edition):
Amorim, E. P. M. (2010). Propriedades mecânicas e eletrônicas de nanofios de cobre e ouro
. (Thesis). Universidade Estadual de Campinas. Retrieved from http://repositorio.unicamp.br/jspui/handle/REPOSIP/277683
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Amorim, Edgard Pacheco Moreira. “Propriedades mecânicas e eletrônicas de nanofios de cobre e ouro
.” 2010. Thesis, Universidade Estadual de Campinas. Accessed March 29, 2020.
http://repositorio.unicamp.br/jspui/handle/REPOSIP/277683.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Amorim, Edgard Pacheco Moreira. “Propriedades mecânicas e eletrônicas de nanofios de cobre e ouro
.” 2010. Web. 29 Mar 2020.
Vancouver:
Amorim EPM. Propriedades mecânicas e eletrônicas de nanofios de cobre e ouro
. [Internet] [Thesis]. Universidade Estadual de Campinas; 2010. [cited 2020 Mar 29].
Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/277683.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Amorim EPM. Propriedades mecânicas e eletrônicas de nanofios de cobre e ouro
. [Thesis]. Universidade Estadual de Campinas; 2010. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/277683
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Universidade Estadual de Campinas
29.
Autreto, Pedro Alves da Silva, 1983-.
Do metal ao carbono : propriedades estruturais e de transporte de novas nanoestruturas
.
Degree: 2011, Universidade Estadual de Campinas
URL: http://repositorio.unicamp.br/jspui/handle/REPOSIP/277660
► Resumo: A nanotecnologia teve seu início simbólico na apresentação de 1959 do Prêmio Nobel Richard Feynman: \"Há muito espaço lá embaixo\". Nesta palestra Feynman destaca…
(more)
▼ Resumo: A nanotecnologia teve seu início simbólico na apresentação de 1959 do Prêmio Nobel Richard Feynman: \"Há muito espaço lá embaixo\". Nesta palestra Feynman destaca as possibilidades de criação de novos materiais, desenhados para possuírem determinadas propriedades eletrônicas e estruturais. Desde então, grandes avanços têm sido feitos e estruturas antes nunca imaginadas têm sido observadas e produzidas. Estas são compostas dos mais diferentes materiais, desde os metais até carbono. Como exemplo de compostos de metais temos os nanofios, as cadeias atômicas lineares e mais atualmente o menor nanotubo de prata. Compostos por carbono também têm recebido grande atenção, como o grafeno. Assim a busca por novas estruturas com propriedades únicas tem se tornado incessante nas últimas décadas. Isso tem tornado cada vez mais importantes às ferramentas teóricas, uma vez que elas podem tanto ajudar na caracterização de novas estruturas, como também as prever, como poderiam ser formadas, qual seria a sua geometria, quais condições seriam necessárias para a sua formação ou demais características eletrônicas. Neste contexto, apresentamos nesta tese, o estudo destas novas nanoestruturas iniciando pelos fatores que influenciam na formação de cadeias atômicas lineares cm nanofios de platina e como a temperatura pode ser essencial para a presença de distâncias anômalas em nanofios de ouro. Cálculos de transporte também foram efetuados para nanofios de ouro e prata, com o fim de correlacionar possíveis geometrias encontradas em experimentos de HRTEM com os perfis de condutância obtidos em experimentos MCBJ. Estudos da evolução do estiramento de nanofios de prata prosseguem com a análise da formação e transporte transporte do menor nanotubo de seção quadrada formada por prata. Formação e estrutura eletrônica de estrutura de carbono topologicamente idêntica a este tubo de prata foi também proposta. Por fim, estudamos as formações do grafano e do fluorografano, a partir da hidrogenação e fluoração de membranas de grafeno, respectivamente; Abstract: Nanotechnology had its symbolical beginning at the 1959\'s Nobel Prize awarder Richard Feynman\'s lecture: \"There is Plenty of Roam at the Bottom\". In this lecture, Feynman highlights the possibilities of creating new materials, designed to have specific electronic and structural properties. Ever since, great advances have been made and structures never dreamed before have been detected and synthesized. These are composed of very many different materials, from metals to carbon. As an example of metal made compounds, we have the nanowires, the linear atomic chains and more recently the smallest silver nanotube. Carbon made compounds have also received great attention; a great example is the graphene. This made the theoretical tools become increasingly important, since they can help both in the characterization of the new structures and in forecasting new ones, how could them be produced, what would its geometry be, which conditions would be necessary for its formation and the other…
Advisors/Committee Members: Galvão, Douglas Soares, 1961- (advisor), Rino, Jose Pedro (committee member), Nunes, Ricardo Wagner (committee member), Rodrigues, Varlei (committee member), Pirota, Kleber Roberto (committee member).
Subjects/Keywords: Nanofios;
Nanotubos;
Estrutura eletrônica;
Ab initio;
Grafeno
Record Details
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Record Details
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❌
APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Autreto, Pedro Alves da Silva, 1. (2011). Do metal ao carbono : propriedades estruturais e de transporte de novas nanoestruturas
. (Thesis). Universidade Estadual de Campinas. Retrieved from http://repositorio.unicamp.br/jspui/handle/REPOSIP/277660
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Autreto, Pedro Alves da Silva, 1983-. “Do metal ao carbono : propriedades estruturais e de transporte de novas nanoestruturas
.” 2011. Thesis, Universidade Estadual de Campinas. Accessed March 29, 2020.
http://repositorio.unicamp.br/jspui/handle/REPOSIP/277660.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Autreto, Pedro Alves da Silva, 1983-. “Do metal ao carbono : propriedades estruturais e de transporte de novas nanoestruturas
.” 2011. Web. 29 Mar 2020.
Vancouver:
Autreto, Pedro Alves da Silva 1. Do metal ao carbono : propriedades estruturais e de transporte de novas nanoestruturas
. [Internet] [Thesis]. Universidade Estadual de Campinas; 2011. [cited 2020 Mar 29].
Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/277660.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Autreto, Pedro Alves da Silva 1. Do metal ao carbono : propriedades estruturais e de transporte de novas nanoestruturas
. [Thesis]. Universidade Estadual de Campinas; 2011. Available from: http://repositorio.unicamp.br/jspui/handle/REPOSIP/277660
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Georgia Tech
30.
Plaisance, Brandon P.
First principles approach to identification of potential ferroelectric and multiferroic molecular materials.
Degree: MS, Chemical and Biomolecular Engineering, 2016, Georgia Tech
URL: http://hdl.handle.net/1853/55039
► Flexible electronics have garnered much interest over the past several decades. Hybrid organic-inorganic materials, such as metal-organic frameworks, offer a unique opportunity to encompass the…
(more)
▼ Flexible electronics have garnered much interest over the past several decades. Hybrid organic-inorganic materials, such as metal-organic frameworks, offer a unique opportunity to encompass the effective electronic properties of the inorganic material and the flexible nature of the organic with the potential of enhancing other desirable properties, such as the contributing multiferroicity. Using a first principles approach, the goal of this thesis is to serve as a guide for identifying potential ferroelectric and multiferroic metal-organic frameworks. This is done through a screening method of metal-organic frameworks based on their geometry; certain symmetry operators cannot be present in a ferroelectric material. We report the theoretical spontaneous polarization for several dozens of MOFs in which ferroelectricity has not previously been tested, and further we discuss the likelihood that these materials could be engineered to have either increased polarization or added ferromagnetism, the latter of which would lead to multiferroicity.
Advisors/Committee Members: Sholl, David S. (advisor), Walton, Krista S. (committee member), Maldovan, Martin (committee member).
Subjects/Keywords: Ferroelectricity; Multiferroicity; Metal-organic frameworks; Ab initio
Record Details
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APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Plaisance, B. P. (2016). First principles approach to identification of potential ferroelectric and multiferroic molecular materials. (Masters Thesis). Georgia Tech. Retrieved from http://hdl.handle.net/1853/55039
Chicago Manual of Style (16th Edition):
Plaisance, Brandon P. “First principles approach to identification of potential ferroelectric and multiferroic molecular materials.” 2016. Masters Thesis, Georgia Tech. Accessed March 29, 2020.
http://hdl.handle.net/1853/55039.
MLA Handbook (7th Edition):
Plaisance, Brandon P. “First principles approach to identification of potential ferroelectric and multiferroic molecular materials.” 2016. Web. 29 Mar 2020.
Vancouver:
Plaisance BP. First principles approach to identification of potential ferroelectric and multiferroic molecular materials. [Internet] [Masters thesis]. Georgia Tech; 2016. [cited 2020 Mar 29].
Available from: http://hdl.handle.net/1853/55039.
Council of Science Editors:
Plaisance BP. First principles approach to identification of potential ferroelectric and multiferroic molecular materials. [Masters Thesis]. Georgia Tech; 2016. Available from: http://hdl.handle.net/1853/55039
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Open Access Theses and Dissertations