subject:(Density functional theory)

University of Georgia

1. Zhang, Jun. Application of the density functional theory: from biomolecules to transition metal complexes.

Degree: PhD, Chemistry, 2007, University of Georgia

URL: http://purl.galileo.usg.edu/uga_etd/zhang_jun_200712_phd

► Density functional theory (DFT), as the most popular method in the modern quantum chemistry field, has been applied to two molecular systems. The first work… (more)

Subjects/Keywords: Density Functional Theory

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APA (6^th Edition):

Zhang, J. (2007). Application of the density functional theory: from biomolecules to transition metal complexes. (Doctoral Dissertation). University of Georgia. Retrieved from http://purl.galileo.usg.edu/uga_etd/zhang_jun_200712_phd

Chicago Manual of Style (16^th Edition):

Zhang, Jun. “Application of the density functional theory: from biomolecules to transition metal complexes.” 2007. Doctoral Dissertation, University of Georgia. Accessed February 27, 2020. http://purl.galileo.usg.edu/uga_etd/zhang_jun_200712_phd.

MLA Handbook (7^th Edition):

Zhang, Jun. “Application of the density functional theory: from biomolecules to transition metal complexes.” 2007. Web. 27 Feb 2020.

Vancouver:

Zhang J. Application of the density functional theory: from biomolecules to transition metal complexes. [Internet] [Doctoral dissertation]. University of Georgia; 2007. [cited 2020 Feb 27]. Available from: http://purl.galileo.usg.edu/uga_etd/zhang_jun_200712_phd.

Council of Science Editors:

Zhang J. Application of the density functional theory: from biomolecules to transition metal complexes. [Doctoral Dissertation]. University of Georgia; 2007. Available from: http://purl.galileo.usg.edu/uga_etd/zhang_jun_200712_phd

University of Georgia

2. Kim, Sunghwan. Applications of density functional theory: radiation-induced DNA damage.

Degree: PhD, Chemistry, 2007, University of Georgia

URL: http://purl.galileo.usg.edu/uga_etd/kim_sunghwan_200705_phd

► Exposure to high-energy radiation can cause mutations in living organisms by generating lethal lesions in DNA strands. Density functional theory has been employed to study… (more)

▼ Exposure to high-energy radiation can cause mutations in living organisms by generating lethal lesions in DNA strands. Density functional theory has been employed to study microhydration effects on formation of the anions of three pyrimidine nucleic acid bases (NABs), thymine, uracil, and cytosine, which are thought to play an important role in the radiation-induced DNA damage process, by explicitly considering various structures of complexes of the three bases with up to five water molecules at the B3LYP/DZP++ level of theory. For all three bases, both the adiabatic electron affinities (AEAs) and vertical detachment energies (VDEs) are found to increase with the number of hydrating water molecules, implying that formation of the anions of the NABs are energetically favorable, although the anions of the NABs in the gas phase are not bound or weakly bound at most. For a given hydration number, uracil is predicted to have the largest electron affinities, while cytosine has the smallest. The methyl group of thymine is found to lower the AEA by 0.04 eV, compared to the AEA of uracil. These results are qualitatively consistent with available experimental results from photodetachment-photoelectron spectroscopy studies of Schiedt et al. [Chem. Phys. 239, 511 (1998)]. The hydrogen-abstracted radicals from the adenine-uracil base pair have also been studied at the B3LYP/DZP++ level of theory. The radical arising from removal of an amino hydrogen of the adenine moiety which forms a hydrogen bond with the uracil O4 atom resulted í1in a significant decrease in the base pair dissociation energy (5.9 kcal mol). This radical is more likely to dissociate into the two isolated bases than to recover the hydrogen bond with the O4 atom through the N6-H bond rotation along the C6-N6 bond. On the contrary, removal of the uracil N3 hydrogen atom does not affect the base pair dissociation energy of the resulting radical, due to electron density transfer from the adenine N1 atom to the uracil N3 atom. Advisors/Committee Members: Henry F. Schaefer, III.

Subjects/Keywords: Density functional theory

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APA (6^th Edition):

Kim, S. (2007). Applications of density functional theory: radiation-induced DNA damage. (Doctoral Dissertation). University of Georgia. Retrieved from http://purl.galileo.usg.edu/uga_etd/kim_sunghwan_200705_phd

Chicago Manual of Style (16^th Edition):

Kim, Sunghwan. “Applications of density functional theory: radiation-induced DNA damage.” 2007. Doctoral Dissertation, University of Georgia. Accessed February 27, 2020. http://purl.galileo.usg.edu/uga_etd/kim_sunghwan_200705_phd.

MLA Handbook (7^th Edition):

Kim, Sunghwan. “Applications of density functional theory: radiation-induced DNA damage.” 2007. Web. 27 Feb 2020.

Vancouver:

Kim S. Applications of density functional theory: radiation-induced DNA damage. [Internet] [Doctoral dissertation]. University of Georgia; 2007. [cited 2020 Feb 27]. Available from: http://purl.galileo.usg.edu/uga_etd/kim_sunghwan_200705_phd.

Council of Science Editors:

Kim S. Applications of density functional theory: radiation-induced DNA damage. [Doctoral Dissertation]. University of Georgia; 2007. Available from: http://purl.galileo.usg.edu/uga_etd/kim_sunghwan_200705_phd

3. wang, lei. Flow Equation Approach to the Hybrid DFT – Anderson Model Description of Actinide Compounds.

Degree: PhD, Physics, 2016, Brown University

URL: https://repository.library.brown.edu/studio/item/bdr:674096/

► Safe storage and disposal of spent fuel rods from nuclear power plants calls for the ability to model actinide complexes and compounds in the environment.… (more)

Subjects/Keywords: Density Functional Theory

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APA (6^th Edition):

wang, l. (2016). Flow Equation Approach to the Hybrid DFT – Anderson Model Description of Actinide Compounds. (Doctoral Dissertation). Brown University. Retrieved from https://repository.library.brown.edu/studio/item/bdr:674096/

Chicago Manual of Style (16^th Edition):

wang, lei. “Flow Equation Approach to the Hybrid DFT – Anderson Model Description of Actinide Compounds.” 2016. Doctoral Dissertation, Brown University. Accessed February 27, 2020. https://repository.library.brown.edu/studio/item/bdr:674096/.

MLA Handbook (7^th Edition):

wang, lei. “Flow Equation Approach to the Hybrid DFT – Anderson Model Description of Actinide Compounds.” 2016. Web. 27 Feb 2020.

Vancouver:

wang l. Flow Equation Approach to the Hybrid DFT – Anderson Model Description of Actinide Compounds. [Internet] [Doctoral dissertation]. Brown University; 2016. [cited 2020 Feb 27]. Available from: https://repository.library.brown.edu/studio/item/bdr:674096/.

Council of Science Editors:

wang l. Flow Equation Approach to the Hybrid DFT – Anderson Model Description of Actinide Compounds. [Doctoral Dissertation]. Brown University; 2016. Available from: https://repository.library.brown.edu/studio/item/bdr:674096/

Wake Forest University

4. Arter, Calvin. FIRST-PRINCIPLES MODELING OF MOF74 FOR GAS SEQUESTRATION AND STORAGE APPLICATIONS.

Degree: 2016, Wake Forest University

URL: http://hdl.handle.net/10339/59283

► The problems associated with anthropogenic climate change arise from the reliance on fossil fuels for energy and the greenhouse gas emissions that are produced. A… (more)

Subjects/Keywords: Density Functional Theory

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APA (6^th Edition):

Arter, C. (2016). FIRST-PRINCIPLES MODELING OF MOF74 FOR GAS SEQUESTRATION AND STORAGE APPLICATIONS. (Thesis). Wake Forest University. Retrieved from http://hdl.handle.net/10339/59283

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Arter, Calvin. “FIRST-PRINCIPLES MODELING OF MOF74 FOR GAS SEQUESTRATION AND STORAGE APPLICATIONS.” 2016. Thesis, Wake Forest University. Accessed February 27, 2020. http://hdl.handle.net/10339/59283.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Arter, Calvin. “FIRST-PRINCIPLES MODELING OF MOF74 FOR GAS SEQUESTRATION AND STORAGE APPLICATIONS.” 2016. Web. 27 Feb 2020.

Vancouver:

Arter C. FIRST-PRINCIPLES MODELING OF MOF74 FOR GAS SEQUESTRATION AND STORAGE APPLICATIONS. [Internet] [Thesis]. Wake Forest University; 2016. [cited 2020 Feb 27]. Available from: http://hdl.handle.net/10339/59283.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Arter C. FIRST-PRINCIPLES MODELING OF MOF74 FOR GAS SEQUESTRATION AND STORAGE APPLICATIONS. [Thesis]. Wake Forest University; 2016. Available from: http://hdl.handle.net/10339/59283

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of New South Wales

5. Pham, Anh. Theoretical investigation of novel spin-polarized materials for spintronic applications.

Degree: Materials Science & Engineering, 2014, University of New South Wales

URL: http://handle.unsw.edu.au/1959.4/54145 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:13290/SOURCE02?view=true

► Development of spin-polarized materials is important for the realization of spintronic devices. Two approaches are taken: (i) investigating magnetism in diluted magnetic semiconductors (DMSs), and… (more)

▼ Development of spin-polarized materials is important for the realization of spintronic devices. Two approaches are taken: (i) investigating magnetism in diluted magnetic semiconductors (DMSs), and (ii) developing novel 2D materials with intrinsic spin currents. The focus of this thesis is to study these two classes of materials using the density functional (DFT) theory.The first part focuses on ZnO based DMS. The systematic study of C/N doped ZnO with defects shows that ZnO:C exhibits ferromagnetism, but dopant complex C2 tends to inhibit this property. Most importantly, the computational method plays a key role in studying DMS. Due to the popularity of hydrogenated ZnO:Co, this system is tested using the different methods. The DFT+U method shows a very specific configuration of hydrogenated Co complex can generate ferromagnetism. The inadequacies of traditional method are further exposed when the dopant geometry is compared between the hybrid functional method and normal DFT. The hybrid method includes the Fock exchange which significantly improves the description of long-range inter-atomic forces in the geometry relaxation yielding a more accurate description. The second part focuses on the study of novel 2D materials with. The studies are devoted to increase the band gap of of novel 2D materials. In silicene and germanene, it is shown that the adsorption and substitution of Tl can increase the bandgaps to 0.29 eV at a small doping limit of ~2%. In addition, Tl can also tune the conductivity of silicene from n to p types depending on the doping sites, and preserving the high mobility of the undoped structure. Furthermore, the author also predicts several new wide bandgap quantum spin Hall insulator (QSHI). QSHI is a novel material with an insulating bulk state and spin-polarized metallic edges. By modifying the surfaces through hydrogenation, the orbital interactions of Bi, Pb, Cr, Mo, and W in the low energy level are confined on two dimensional resulting in novel QSHI with giant gap and strongly correlated property. These results represent important contribution to the study of spintronic materials. First, the understanding between the theoretical method and magnetic properties in semiconductors can help to accurately predict new spintronic materials. Most importantly, the study in orbital engineering of 2D materials with hydrogenation provides new insights into the nature topological materials which have practical applications for the next generation of electronic devices. Advisors/Committee Members: Li, Sean, Materials Science & Engineering, Faculty of Science, UNSW.

Subjects/Keywords: Magnetism; Density functional theory; Spintronics

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APA (6^th Edition):

Pham, A. (2014). Theoretical investigation of novel spin-polarized materials for spintronic applications. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/54145 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:13290/SOURCE02?view=true

Chicago Manual of Style (16^th Edition):

Pham, Anh. “Theoretical investigation of novel spin-polarized materials for spintronic applications.” 2014. Doctoral Dissertation, University of New South Wales. Accessed February 27, 2020. http://handle.unsw.edu.au/1959.4/54145 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:13290/SOURCE02?view=true.

MLA Handbook (7^th Edition):

Pham, Anh. “Theoretical investigation of novel spin-polarized materials for spintronic applications.” 2014. Web. 27 Feb 2020.

Vancouver:

Pham A. Theoretical investigation of novel spin-polarized materials for spintronic applications. [Internet] [Doctoral dissertation]. University of New South Wales; 2014. [cited 2020 Feb 27]. Available from: http://handle.unsw.edu.au/1959.4/54145 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:13290/SOURCE02?view=true.

Council of Science Editors:

Pham A. Theoretical investigation of novel spin-polarized materials for spintronic applications. [Doctoral Dissertation]. University of New South Wales; 2014. Available from: http://handle.unsw.edu.au/1959.4/54145 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:13290/SOURCE02?view=true

Oregon State University

6. Schulte, Jeff B. Hard spheres within classical density functional theory and Min proteins in Escherichia coli.

Degree: PhD, Physics, 2015, Oregon State University

URL: http://hdl.handle.net/1957/55645

► This thesis reports on computational research in two different areas. I first discuss the Min-protein system found within Escherichia coli. Following this I discuss an… (more)

▼ This thesis reports on computational research in two different areas. I first discuss the Min-protein system found within Escherichia coli. Following this I discuss an extended investigation into improving free energy functionals that are used within Classical Density Functional Theory in order to model water. Chapter 2 examines the dynamics of the Min-protein system within E. Coli, which aid in regulating the process of cell division by identifying the center of the cell. While this system usually exhibits robust bipolar oscillations in a variety of cell shapes, recent experiments have shown that when the cells are mechanically deformed into wide, flattened out, irregular shapes, the spatial regularity of these oscillations breaks down. We employ widely used stochastic and deterministic models of the Min system to simulate cells with flattened shapes. The deterministic model predicts regular bipolar oscillations, in contradiction with the experimentally observed behavior, while the single molecule nature of the stochastic model, which is based on the same reaction-diffusion equations, leads to the disruption of the regular patterns of protein concentration. We further report on simulations of symmetric but flattened cell shapes, and find that it is the flattening and accompanying lateral expansion rather than the asymmetry of the cell shapes that causes the irregular oscillation behavior. Chapter 3 begins our discussion of Classical Density Functional Theory research by introducing many of the key concepts used in the following chapters. Chapter 4 investigates the value of the distribution function of an inhomogeneous hard-sphere fluid at contact. This quantity plays a critical role in statistical associating fluid theory, which is the basis of a number of recently developed classical density functionals, including ones developed within my research group. We define two averaged values for the distribution function at contact and derive formulas for each of them from the White Bear version of the fundamental measure theory functional, using an assumption of thermodynamic consistency. We test these formulas, as well as two existing formulas, against Monte Carlo simulations and find excellent agreement between the Monte Carlo data and one of our averaged distribution functions. Chapter 5 details our modifications of our recently published statistical associating fluid theory-based classical density functional theory for water, incorporating this improved distribution function at contact. We examine the effect of this alteration by studying two hard-sphere solutes and a Lennard-Jones approximation of a krypton-atom solute, and find improvement. Finally, Chapter 6 introduces an approximation for the pair distribution function of the inhomogeneous hard sphere fluid. Our approximation makes use of the new distribution function at contact referred to above. This approach achieves greater computational efficiency than previous approaches by enabling the use of exclusively fixed-kernel convolutions, which allows for an… Advisors/Committee Members: Roundy, David J. (advisor), Jansen, Henri J. (committee member).

Subjects/Keywords: Classical Density Functional Theory; Density functionals

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APA (6^th Edition):

Schulte, J. B. (2015). Hard spheres within classical density functional theory and Min proteins in Escherichia coli. (Doctoral Dissertation). Oregon State University. Retrieved from http://hdl.handle.net/1957/55645

Chicago Manual of Style (16^th Edition):

Schulte, Jeff B. “Hard spheres within classical density functional theory and Min proteins in Escherichia coli.” 2015. Doctoral Dissertation, Oregon State University. Accessed February 27, 2020. http://hdl.handle.net/1957/55645.

MLA Handbook (7^th Edition):

Schulte, Jeff B. “Hard spheres within classical density functional theory and Min proteins in Escherichia coli.” 2015. Web. 27 Feb 2020.

Vancouver:

Schulte JB. Hard spheres within classical density functional theory and Min proteins in Escherichia coli. [Internet] [Doctoral dissertation]. Oregon State University; 2015. [cited 2020 Feb 27]. Available from: http://hdl.handle.net/1957/55645.

Council of Science Editors:

Schulte JB. Hard spheres within classical density functional theory and Min proteins in Escherichia coli. [Doctoral Dissertation]. Oregon State University; 2015. Available from: http://hdl.handle.net/1957/55645

7. Lehtinen, Petri Olavi. Magnetic Nature of Intrinsic Carbon Defects.

Degree: 2005, Helsinki University of Technology

URL: http://lib.tkk.fi/Diss/2005/isbn951227521X/

►

Magnetism is a phenomenon that has been known for a very long time. Iron, cobalt, and nickel are known ferromagnetic materials. It is less known,… (more)

▼

Magnetism is a phenomenon that has been known for a very long time. Iron, cobalt, and nickel are known ferromagnetic materials. It is less known, probably because it is so unexpected, that even carbon can have ferromagnetic behaviour. Experimentally this has been confirmed on many occasions within the last decade. Ferromagnetic behaviour of carbon provides an example of the fact that magnetism is not well understood at the atomic scale. One of the aims of this thesis is to study and understand possible sources of ferromagnetism in carbon systems, thereby creating a possible foundation for the next generation of ferromagnets. Carbon itself is a very interesting substance with numerous interesting properties. In the late 1980s and early 1990s new carbon allotropes were found, such as fullerenes (bucky balls) and nanotubes (cylinders), next to the old ones (graphite and diamond). Especially nanotubes have been considered as candidates for several future applications. Whatever the fabrication process, all allotropes of carbon will have intrinsic defects, and in this thesis the role of these defects in carbon magnetism is investigated in detail. Studying magnetism requires "state-of-the-art"-methods due to the demand of high accuracy because energy differences between non-magnetic and magnetic cases are usually very small. Ab initio methods are usually the best for such studies, especially methods based on the density functional theory. Here, a state-of-art method which is based on the density functional theory and implementing projector augmented waves to model the properties of carbon is used. Adatoms and vacancies are found to have magnetic moments of 0.5 μB and 1.0 μB, respectively. In practice, however, the high mobility of adatoms on graphene at room temperature would suggest that many of them recombine with vacancies or cluster together, destroying their magnetism. Despite the indications that a barrier to vacancy-interstitial pair recombination exists, efficient recombination seems to be confirmed by He-irradiation experiments. The magnetic signal was small despite the fact that the amount of defects created by the He ions is large. Also, the effect of the changing electronic structure on the magnetic moments of adatoms and vacancies is studied with the help of nanotubes. On nanotubes, the magnetism of an adatom decreases because of the curvature and differences in electronic structures while the magnetic moment of a vacancy in all but strongly metallic tubes is destroyed. The experimental demonstration of induced ferromagnetism by proton irradiation on graphite indicates a promising direction for creating a magnetic carbon system in a controllable way. Simulations indicate that this is due to a combination of a hydrogen atom trapping at vacancies and pinning of mobile adatoms, producing magnetic C-H complexes and uncompensated vacancies.

Dissertations / Laboratory of Physics, Helsinki University of Technology, ISSN 1455-1802; 129

Advisors/Committee Members: Helsinki University of Technology, Department of Engineering Physics and Mathematics, Laboratory of Physics.

Subjects/Keywords: density functional theory; carbon; graphite; nanotube; magnetism

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APA (6^th Edition):

Lehtinen, P. O. (2005). Magnetic Nature of Intrinsic Carbon Defects. (Thesis). Helsinki University of Technology. Retrieved from http://lib.tkk.fi/Diss/2005/isbn951227521X/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Lehtinen, Petri Olavi. “Magnetic Nature of Intrinsic Carbon Defects.” 2005. Thesis, Helsinki University of Technology. Accessed February 27, 2020. http://lib.tkk.fi/Diss/2005/isbn951227521X/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Lehtinen, Petri Olavi. “Magnetic Nature of Intrinsic Carbon Defects.” 2005. Web. 27 Feb 2020.

Vancouver:

Lehtinen PO. Magnetic Nature of Intrinsic Carbon Defects. [Internet] [Thesis]. Helsinki University of Technology; 2005. [cited 2020 Feb 27]. Available from: http://lib.tkk.fi/Diss/2005/isbn951227521X/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Lehtinen PO. Magnetic Nature of Intrinsic Carbon Defects. [Thesis]. Helsinki University of Technology; 2005. Available from: http://lib.tkk.fi/Diss/2005/isbn951227521X/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Georgia

8. Wannere, Chaitanya Shridhar. Structures, energetics, and magnetic property evaluations using density functional theory.

Degree: PhD, Chemistry, 2003, University of Georgia

URL: http://purl.galileo.usg.edu/uga_etd/wannere_chaitany_200312_phd

► I have applied density functional theory (DFT) to various problems in organic and inorganic chemistry. The use of various DFT levels has rigorously been tested… (more)

▼ I have applied density functional theory (DFT) to various problems in organic and inorganic chemistry. The use of various DFT levels has rigorously been tested to assess the reliability of these methods to accurately compute structures and energies. The B3LYP DFT theory with a reasonably large basis sets is sufficiently accurate. In few cases, however, B3LYP leads to serious errors in predicting the ground state structures. Work employing the B3LYP method to investigate the reaction of phosphaethene with 1,3-dienes revealed that the structures of the reactants and products and their energies were sufficiently accurate to explain the experimental regioselectivites. Additionally the B3LYP method also accurately reproduce the 1H NMR chemical shifts. In the study regarding the stability of [4n]annulenes (antiaromatic hydrocarbons), the use of an appropriate isodesmic equation can give B3LYP stabilization energies which are in excellent agreement with those given by other methods. In these cases, results from B3LYP-DFT were sufficiently accurate and reliable. Computationally challenging for all the DFT methods was the prediction of structures and energies of [4n+2]annulenes. The widely accepted X-ray and B3LYP indicated CC bond equalized structures of [14]-, [18]-, and [22]annulenes are found to be incorrect since the computed proton chemical shifts using these geometries gave ä 1Hs which are in gross disagreement with the experimental values. Instead lower symmetry structures with CC bond alternation are given by KMLYP and BHLYP DFT methods. These lower symmetry structures are found to be more stable, as also confirmed by the CCSD(T) method, and give proton chemical shifts in excellent agreement with experimental values. Our application of the B3LYP level to various problems indicates that this method, in general, is reliable for computing accurate structures and energies. However, in a few cases caution is indicated when applying the B3LYP method, this study suggests that the KMLYP is capable of predicting structures more reliably than the B3LYP method. We also propose that data sets containing aromatic annulenes (larger than benzene) could serve as the basis for developing even better hybridizations of density functional and other methods. Advisors/Committee Members: Paul V. R. Schleyer.

Subjects/Keywords: Density Functional Theory

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APA (6^th Edition):

Wannere, C. S. (2003). Structures, energetics, and magnetic property evaluations using density functional theory. (Doctoral Dissertation). University of Georgia. Retrieved from http://purl.galileo.usg.edu/uga_etd/wannere_chaitany_200312_phd

Chicago Manual of Style (16^th Edition):

Wannere, Chaitanya Shridhar. “Structures, energetics, and magnetic property evaluations using density functional theory.” 2003. Doctoral Dissertation, University of Georgia. Accessed February 27, 2020. http://purl.galileo.usg.edu/uga_etd/wannere_chaitany_200312_phd.

MLA Handbook (7^th Edition):

Wannere, Chaitanya Shridhar. “Structures, energetics, and magnetic property evaluations using density functional theory.” 2003. Web. 27 Feb 2020.

Vancouver:

Wannere CS. Structures, energetics, and magnetic property evaluations using density functional theory. [Internet] [Doctoral dissertation]. University of Georgia; 2003. [cited 2020 Feb 27]. Available from: http://purl.galileo.usg.edu/uga_etd/wannere_chaitany_200312_phd.

Council of Science Editors:

Wannere CS. Structures, energetics, and magnetic property evaluations using density functional theory. [Doctoral Dissertation]. University of Georgia; 2003. Available from: http://purl.galileo.usg.edu/uga_etd/wannere_chaitany_200312_phd

University of Georgia

9. Li, Se. Application of quantum mechanical computational techniques: the unsatured binuclear chromium carbonyls and singlet excited electronic states of aluminum hydroxide.

Degree: PhD, Chemistry, 2004, University of Georgia

URL: http://purl.galileo.usg.edu/uga_etd/li_se_200405_phd

► Advanced quantum mechanical computational techniques have been applied to probe two disparate systems. First, density functional theory (DFT) is used to obtain the first structural… (more)

▼ Advanced quantum mechanical computational techniques have been applied to probe two disparate systems. First, density functional theory (DFT) is used to obtain the first structural characterizations of the unsaturated dichromium carbonyl complexes Cr2(CO)x (x=10, 9, 8), which may contain metal-metal multiple bonds. Chromium is unique among the first row transition metal elements in its ability to form compounds with multiple bonds in the formal metal oxidation state chromium(0). The global minimum energy structure of Cr2(CO)10 for the lowest singlet state of C2h symmetry is consistent with a model of two interacting Cr(CO)5 fragments, with chromium-chromium distances of 2.93 Å (B3LYP) or 2.83 Å (BP86). The minimum energy Cr2(CO)9 structure of Cs symmetry is predicted to have a remarkably short metal-metal bond length of 2.31 Å (B3LYP) or 2.28 Å (BP86). This chromium-chromium distance is essentially identical to that reported experimentally for the established CrºCr triple bond in (h5-Me5C5)2Cr2(CO)4. Cr2(CO)8 is predicted to have a short metal-metal bond length of 2.30 Å (B3LYP) or 2.28 Å (BP86) for the minimum energy structure of Cs symmetry. Second, extensive ab initio quantum mechanical methods have been employed to five lowest-lying electronic singlet states of astrophysically interesting AlOH, particularly for the two excited singlet states. To avoid the difficulty involved in applying multi-reference methods, we use the equation-of-motion coupled cluster method. The first singlet excited state (Ã 1A¢) is predicted to have a bond angle of 110° and to lie 114 kcal/mol (39 900 cm.1, 4.94 eV) above the ground state, whereas the second singlet excited state (B 1A²) is predicted to have a bond angle of 116° and to be located 119 kcal/mol (41 700 cm.1, 5.17 eV) above the ground state. These theoretical energy separations are in excellent agreement with the experimental values T0 (Ã 1A¢) = 114.57 kcal/mol (40 073 cm.1, 4.968 eV) and T0 (B1A²) = 119.36 kcal/mol (41 747 cm.1, 5.176 eV). Advisors/Committee Members: H. F. Schaefer.

Subjects/Keywords: Density Functional Theory

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APA (6^th Edition):

Li, S. (2004). Application of quantum mechanical computational techniques: the unsatured binuclear chromium carbonyls and singlet excited electronic states of aluminum hydroxide. (Doctoral Dissertation). University of Georgia. Retrieved from http://purl.galileo.usg.edu/uga_etd/li_se_200405_phd

Chicago Manual of Style (16^th Edition):

Li, Se. “Application of quantum mechanical computational techniques: the unsatured binuclear chromium carbonyls and singlet excited electronic states of aluminum hydroxide.” 2004. Doctoral Dissertation, University of Georgia. Accessed February 27, 2020. http://purl.galileo.usg.edu/uga_etd/li_se_200405_phd.

MLA Handbook (7^th Edition):

Li, Se. “Application of quantum mechanical computational techniques: the unsatured binuclear chromium carbonyls and singlet excited electronic states of aluminum hydroxide.” 2004. Web. 27 Feb 2020.

Vancouver:

Li S. Application of quantum mechanical computational techniques: the unsatured binuclear chromium carbonyls and singlet excited electronic states of aluminum hydroxide. [Internet] [Doctoral dissertation]. University of Georgia; 2004. [cited 2020 Feb 27]. Available from: http://purl.galileo.usg.edu/uga_etd/li_se_200405_phd.

Council of Science Editors:

Li S. Application of quantum mechanical computational techniques: the unsatured binuclear chromium carbonyls and singlet excited electronic states of aluminum hydroxide. [Doctoral Dissertation]. University of Georgia; 2004. Available from: http://purl.galileo.usg.edu/uga_etd/li_se_200405_phd

University of Georgia

10. Papas, Brian Nicholas. Benchmarking and application of density functional methods in computational chemistry.

Degree: PhD, Chemistry, 2006, University of Georgia

URL: http://purl.galileo.usg.edu/uga_etd/papas_brian_n_200605_phd

► Density Functional methods were applied to systems of chemical interest. First, the effects of integration grid quadrature choice upon energy precision were documented. This was… (more)

▼ Density Functional methods were applied to systems of chemical interest. First, the effects of integration grid quadrature choice upon energy precision were documented. This was done through application of DFT theory as implemented in five standard computational chemistry programs to a subset of the G2/97 test set of molecules. Subsequently, the neutral hydrogen-loss radicals of naphthalene, anthracene, tetracene, and pentacene and their anions where characterized using five standard DFT treatments. The global and local electron affinities were computed for the twelve radicals. The results for the 1- naphthalenyl and 2-naphthalenyl radicals were compared to experiment, and it was found that B3LYP appears to be the most reliable functional for this type of system. For the larger systems the predicted site specific adiabatic electron affinities of the radicals are 1.51 eV (1-anthracenyl), 1.46 eV (2-anthracenyl), 1.68 eV (9-anthracenyl); 1.61 eV (1-tetracenyl), 1.56 eV (2-tetracenyl), 1.82 eV (12-tetracenyl); 1.93 eV (14-pentacenyl), 2.01 eV (13-pentacenyl), 1.68 eV (1-pentacenyl), and 1.63 eV (2-pentacenyl). The global minimum for each radical does not have the same hydrogen removed as the global minimum for the analogous anion. With this in mind, the global (or most preferred site) adiabatic electron affinities are 1.37 eV (naphthalenyl), 1.64 eV (anthracenyl), 1.81 eV (tetracenyl), and 1.97 eV (pentacenyl). In later work, ten (scandium through zinc) homonuclear transition metal trimers were studied using one DFT functional. Electronic ground states and bond lengths for equilateral triangles were: Sc3 (2A1 ' , 2.83 Å), Ti3 (7E ' , 2.32), V3 (2E . , 2.06), Cr3 (17E ' , 2.92), Mn3 (16A2 ' , 2.73), Fe3 (11E . , 2.24), Co3 (6E . , 2.18), Ni3 (3A2. , 2.23), Cu3 (2E ' , 2.37), Zn3 (1A1 ' , 2.93). Vibrational frequencies, several low-lying electronic states, and trends in bond lengths and atomization energies are discussed. The predicted dissociation energies .E (M3 . M2 + M) are 49.4 kcal mol-1 (Sc3), 64.3 kcal mol-1 (Ti3), 60.7 kcal mol-1 (V3), 11.5 kcal mol-1 (Cr3), 32.4 kcal mol-1 (Mn3), 61.5 kcal mol-1 (Fe3), 78.0 kcal mol-1 (Co3), 86.1 kcal mol-1 (Ni3), 26.8 kcal mol-1 (Cu3), and 4.5 kcal mol-1 (Zn3). Advisors/Committee Members: H. F. Schaefer.

Subjects/Keywords: Density Functional Theory

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APA (6^th Edition):

Papas, B. N. (2006). Benchmarking and application of density functional methods in computational chemistry. (Doctoral Dissertation). University of Georgia. Retrieved from http://purl.galileo.usg.edu/uga_etd/papas_brian_n_200605_phd

Chicago Manual of Style (16^th Edition):

Papas, Brian Nicholas. “Benchmarking and application of density functional methods in computational chemistry.” 2006. Doctoral Dissertation, University of Georgia. Accessed February 27, 2020. http://purl.galileo.usg.edu/uga_etd/papas_brian_n_200605_phd.

MLA Handbook (7^th Edition):

Papas, Brian Nicholas. “Benchmarking and application of density functional methods in computational chemistry.” 2006. Web. 27 Feb 2020.

Vancouver:

Papas BN. Benchmarking and application of density functional methods in computational chemistry. [Internet] [Doctoral dissertation]. University of Georgia; 2006. [cited 2020 Feb 27]. Available from: http://purl.galileo.usg.edu/uga_etd/papas_brian_n_200605_phd.

Council of Science Editors:

Papas BN. Benchmarking and application of density functional methods in computational chemistry. [Doctoral Dissertation]. University of Georgia; 2006. Available from: http://purl.galileo.usg.edu/uga_etd/papas_brian_n_200605_phd

University of Exeter

11. Fujita, Naomi. Modelling of point and extended defects in Group IV semiconductors.

Degree: PhD, 2009, University of Exeter

URL: http://hdl.handle.net/10036/90563

► In this thesis first-principles calculations of point and extended defects in diamond and silicon are reported. In single crystal diamond grown by chemical vapour deposition… (more)

▼ In this thesis first-principles calculations of point and extended defects in diamond and silicon are reported. In single crystal diamond grown by chemical vapour deposition (CVD) dislocations are observed as mixed-type 45° and edge-type dislocations lying along <100> with 1/2<110> Burgers vectors. Results are presented on the core structures, core energies and electrical properties of both types of dislocations and their interaction with nitrogen is investigated. Then the focus turns to the brown diamond problem. Despite concerted research efforts, the origin of the brown colouration of diamond is still under discussion. Recently, the attention was drawn to vacancy-related defects. Experiments on type IIa diamonds indicate that the brown colour is caused by vacancy-type extended defects, however the shape and size of these defects remained unclear. In this work, the structural, electrical and optical properties of large spherical vacancy clusters and thin vacancy disks are investigated by means of density functional theory and the calculations are compared with recent experimental measurements on brown diamond. High pressure high temperature treatment (HPHT) of brown type Ia diamonds above 2000°C results in the loss of the brown colour and the formation of nitrogen-vacancy defects. The generation of such defects requires a source of mobile vacancies during the annealing process. It is suggested that the vacancy cluster model described in this thesis can explain the observed annealing behaviour since the break-up of the clusters leads to a supersaturation of mobile vacancies which readily complex with substitutional nitrogen atoms present in the material. Therefore, the effect of HPHT treatment of brown type Ia diamond is investigated by studying the formation energies of common and rare defects and estimates of their equilibrium concentrations at different annealing stages are given. Finally, an open problem also involving nitrogen, but in a different group IV semiconductor is considered. In Czochralski-silicon, nitrogen-related shallow thermal donors are formed between 500 and 750°C. Until now the exact chemical composition and atomic structure of these defects are not well established. Here, it is shown that NO and NO_2 belong to the family of nitrogen-oxygen related shallow thermal donors. Based on the law of mass action the equilibrium defect concentrations are predicted. Finally, the theoretical results are compared to recent Fourier transform infrared (FTIR) spectroscopy measurements.

Subjects/Keywords: 537.622; density functional theory : defects : diamond : silicon

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Fujita, N. (2009). Modelling of point and extended defects in Group IV semiconductors. (Doctoral Dissertation). University of Exeter. Retrieved from http://hdl.handle.net/10036/90563

Chicago Manual of Style (16^th Edition):

Fujita, Naomi. “Modelling of point and extended defects in Group IV semiconductors.” 2009. Doctoral Dissertation, University of Exeter. Accessed February 27, 2020. http://hdl.handle.net/10036/90563.

MLA Handbook (7^th Edition):

Fujita, Naomi. “Modelling of point and extended defects in Group IV semiconductors.” 2009. Web. 27 Feb 2020.

Vancouver:

Fujita N. Modelling of point and extended defects in Group IV semiconductors. [Internet] [Doctoral dissertation]. University of Exeter; 2009. [cited 2020 Feb 27]. Available from: http://hdl.handle.net/10036/90563.

Council of Science Editors:

Fujita N. Modelling of point and extended defects in Group IV semiconductors. [Doctoral Dissertation]. University of Exeter; 2009. Available from: http://hdl.handle.net/10036/90563

Victoria University of Wellington

12. Leeb, Nina. Tracking the Source of Enantioselectivity.

Degree: 2015, Victoria University of Wellington

URL: http://hdl.handle.net/10063/4906

► Enantioselectivity remains one of synthetic chemistry’s most formidable problems. It arises due to the formation of diastereomeric species in a reaction, either in the form… (more)

▼ Enantioselectivity remains one of synthetic chemistry’s most formidable problems. It arises due to the formation of diastereomeric species in a reaction, either in the form of diastereomeric intermediates or a set of diastereomeric transition states. Without control a racemic mixture is formed. A resolution method is then required to separate the enantiomers. Any given resolution method will rely on the differing energies of diastereomers to allow for their separation. Experimentally there are a myriad of different options that may be used to induce separation; for example chromatography and/or crystallisation. The actual process that occurs through- out this separation has not, however, been fully investigated in all cases. A better understanding of the process is able to provide an understanding of how resolution methods work i.e. when diastereomers occur and how great their energy differences are. This is vital in increasing the efficiency and effectiveness of any given resolution method. This theoretical study completed an investigation of the reaction pathway between the enantiomers of 2-formyl-3-hydroxyl[2.2]paracyclophane (FHPC) with (S)-valyl-(S)-valine. A subsequent investigation of an alternative resolution method, involving (R)-α-PEAM, was also conducted. This latter resolution method was proposed experimentally as a simpler method that could aid in improving the separation of the enantiomers. This investigation was carried out using Density Functional Theory (DFT) with the PBE0 functional and the triple-ζ TZVP basis set. The complete reaction profile was determined and diastereomeric intermediates and transition states for both resolution methods along two different pathways were determined; the ‘N-deprotonation Pathway’ and the ‘O-deprotonation Pathway’. The inadequacy of the first resolution method was found to be due to the presence of copper(II). Furthermore it was discovered that the re- action for both pathways would most likely proceed through the ‘O-deprotonation Pathway’ due to the barriers being lower in energy. Advisors/Committee Members: Lein, Matthias.

Subjects/Keywords: DFT; Chiral resolution; Cyclophane; Density Functional Theory

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APA (6^th Edition):

Leeb, N. (2015). Tracking the Source of Enantioselectivity. (Masters Thesis). Victoria University of Wellington. Retrieved from http://hdl.handle.net/10063/4906

Chicago Manual of Style (16^th Edition):

Leeb, Nina. “Tracking the Source of Enantioselectivity.” 2015. Masters Thesis, Victoria University of Wellington. Accessed February 27, 2020. http://hdl.handle.net/10063/4906.

MLA Handbook (7^th Edition):

Leeb, Nina. “Tracking the Source of Enantioselectivity.” 2015. Web. 27 Feb 2020.

Vancouver:

Leeb N. Tracking the Source of Enantioselectivity. [Internet] [Masters thesis]. Victoria University of Wellington; 2015. [cited 2020 Feb 27]. Available from: http://hdl.handle.net/10063/4906.

Council of Science Editors:

Leeb N. Tracking the Source of Enantioselectivity. [Masters Thesis]. Victoria University of Wellington; 2015. Available from: http://hdl.handle.net/10063/4906

University of Minnesota

13. Marell, Daniel. Understanding Organic Reaction Mechanisms Through Applications of Density-Functional Theory.

Degree: PhD, Chemistry, 2016, University of Minnesota

URL: http://hdl.handle.net/11299/182795

► The application of computational chemistry has a wide scope of utility. From large systems such as proteins or metal-organic frameworks down to the understanding of… (more)

▼ The application of computational chemistry has a wide scope of utility. From large systems such as proteins or metal-organic frameworks down to the understanding of individual bonding patterns between atoms, there are endless opportunities to explore. Further utility is gained when the insights and resources of computational chemists can be applied to systems under investigation by experimental chemists The combined information of computational details with experimental findings can lead to new understanding of the systems being investigated. The ring-opening transesterification polymerization of caprolactone with an aluminum- salen catalyst is a useful reaction for the conversion of caprolactone to polyester. Mechanistic understanding of this reaction was gained through the interrogation of this process with density functional theory. Further, the origins for rate-enhancement through modification of electron-withdrawing groups was explained through the analysis of partial atomic charges. A rate enhancement observed by altering the backbone of the catalyst was also explained through the development of a distortion framework analysis. Rieske oxygenase are a class of protein that executes a variety of chemical reactions such as oxygenations, O- and N-demethylations, oxidations, and C–C bond formations en route to the formation of medically relevant natural products. The continued elucidation of the mechanism, including the characterization of reactive species was persued. Computational work to understand the impact partial atomic charge on the aromatic system (by inclusion of fluorine substituents) had on the rate constant demonstrated a clear correlation between the partial atomic charge on the C(2) position and the rate constant for a variety of substrates. A new reaction, the hexadehydro-Diels–Alder (HDDA) reaction takes a diyne and a diynophile to create a reactive benzyne intermediate. A series of six intramolecular HDDA substrates were found to undergo this transformation at relatively similar rates. Analysis of transition state geometries, investigation of both closed-shell and diradical mechanistic pathways, as well as insight from high-level calculations provide information about the nature of this intramolecular reaction. Extension of the mechanism led to predictive capability in good agreement with a new set of substrates as well.

Subjects/Keywords: density-functional theory; polymerization; reaction mechanism

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Marell, D. (2016). Understanding Organic Reaction Mechanisms Through Applications of Density-Functional Theory. (Doctoral Dissertation). University of Minnesota. Retrieved from http://hdl.handle.net/11299/182795

Chicago Manual of Style (16^th Edition):

Marell, Daniel. “Understanding Organic Reaction Mechanisms Through Applications of Density-Functional Theory.” 2016. Doctoral Dissertation, University of Minnesota. Accessed February 27, 2020. http://hdl.handle.net/11299/182795.

MLA Handbook (7^th Edition):

Marell, Daniel. “Understanding Organic Reaction Mechanisms Through Applications of Density-Functional Theory.” 2016. Web. 27 Feb 2020.

Vancouver:

Marell D. Understanding Organic Reaction Mechanisms Through Applications of Density-Functional Theory. [Internet] [Doctoral dissertation]. University of Minnesota; 2016. [cited 2020 Feb 27]. Available from: http://hdl.handle.net/11299/182795.

Council of Science Editors:

Marell D. Understanding Organic Reaction Mechanisms Through Applications of Density-Functional Theory. [Doctoral Dissertation]. University of Minnesota; 2016. Available from: http://hdl.handle.net/11299/182795

University of New Mexico

14. Johnson, Ryan. Theoretical Studies of Transition Metal Catalysis.

Degree: Department of Chemistry and Chemical Biology, 2014, University of New Mexico

URL: https://digitalrepository.unm.edu/chem_etds/38

► Transition metal catalysis, being critical to nearly all aspects of the modern industrial world, is the focus of a series of theoretical studies which seek… (more)

Subjects/Keywords: Catalysis; Transition metals; Density functional theory

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APA (6^th Edition):

Johnson, R. (2014). Theoretical Studies of Transition Metal Catalysis. (Doctoral Dissertation). University of New Mexico. Retrieved from https://digitalrepository.unm.edu/chem_etds/38

Chicago Manual of Style (16^th Edition):

Johnson, Ryan. “Theoretical Studies of Transition Metal Catalysis.” 2014. Doctoral Dissertation, University of New Mexico. Accessed February 27, 2020. https://digitalrepository.unm.edu/chem_etds/38.

MLA Handbook (7^th Edition):

Johnson, Ryan. “Theoretical Studies of Transition Metal Catalysis.” 2014. Web. 27 Feb 2020.

Vancouver:

Johnson R. Theoretical Studies of Transition Metal Catalysis. [Internet] [Doctoral dissertation]. University of New Mexico; 2014. [cited 2020 Feb 27]. Available from: https://digitalrepository.unm.edu/chem_etds/38.

Council of Science Editors:

Johnson R. Theoretical Studies of Transition Metal Catalysis. [Doctoral Dissertation]. University of New Mexico; 2014. Available from: https://digitalrepository.unm.edu/chem_etds/38

The Ohio State University

15. Stoltzfus, Matthew W. Structure-property relationships in solid state materials: a computational approach emphasizing chemical bonding.

Degree: PhD, Chemistry, 2007, The Ohio State University

URL: http://rave.ohiolink.edu/etdc/view?acc_num=osu1190087366

► Density functional theory (DFT) calculations were performed to investigate the orbital interactions responsible for stereoactive lone pair distortions in ternary metal oxides. The calculations revealed… (more)

Subjects/Keywords: Chemistry, Inorganic; Density Functional Theory; Lone Pairs

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APA (6^th Edition):

Stoltzfus, M. W. (2007). Structure-property relationships in solid state materials: a computational approach emphasizing chemical bonding. (Doctoral Dissertation). The Ohio State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=osu1190087366

Chicago Manual of Style (16^th Edition):

Stoltzfus, Matthew W. “Structure-property relationships in solid state materials: a computational approach emphasizing chemical bonding.” 2007. Doctoral Dissertation, The Ohio State University. Accessed February 27, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1190087366.

MLA Handbook (7^th Edition):

Stoltzfus, Matthew W. “Structure-property relationships in solid state materials: a computational approach emphasizing chemical bonding.” 2007. Web. 27 Feb 2020.

Vancouver:

Stoltzfus MW. Structure-property relationships in solid state materials: a computational approach emphasizing chemical bonding. [Internet] [Doctoral dissertation]. The Ohio State University; 2007. [cited 2020 Feb 27]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1190087366.

Council of Science Editors:

Stoltzfus MW. Structure-property relationships in solid state materials: a computational approach emphasizing chemical bonding. [Doctoral Dissertation]. The Ohio State University; 2007. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=osu1190087366

University of Toledo

16. Shi, Tingting. Optoelectronic and Defect Properties in Earth Abundant Photovoltaic Materials: First-principle Calculations.

Degree: PhD, College of Natural Sciences and Mathematics, 2014, University of Toledo

URL: http://rave.ohiolink.edu/etdc/view?acc_num=toledo1418391935

► In this dissertation, a series of earth-abundant photovoltaic materials including lead halide perovskites, copper based compounds, and silicon are investigated via density functional theory (DFT).… (more)

▼ In this dissertation, a series of earth-abundant photovoltaic materials including lead halide perovskites, copper based compounds, and silicon are investigated via density functional theory (DFT). Firstly, we study the unique optoelectronic properties of perovskite CH3NH3PbI3 and CH3NH3PbBr3. First-principle calculations show that CH3NH3PbI3 perovskite solar cells exhibit remarkable optoelectronic properties that account for the high open circuit voltage (Voc) and long electron-hole diffusion lengths. Our results reveal that for intrinsic doping, dominant point defects produce only shallow levels. Therefore lead halide perovskites are expected to exhibit intrinsic low non-radiative recombination rates. The conductivity of perovskites can be tuned from p-type to n-type by controlling the growth conditions. For extrinsic defects, the p-type perovskites can be achieved by doping group-IA, -IB, or -VIA elements, such as Na, K, Rb, Cu, and O at I-rich growth conditions. We further show that despite a large band gap of 2.2 eV, the dominant defects in CH3NH3PbBr3 also create only shallow levels. The photovoltaic properties of CH3NH3PbBr3–based perovskite absorbers can be tuned via defect engineering. Highly conductive p-type CH3NH3PbBr3 can be synthesized under Br-rich growth conditions. Such CH3NH3PbBr3 may be potential low-cost hole transporting materials for lead halide perovskite solar cells. All these unique defect properties of perovskites are largely due to the strong Pb lone-pair s orbital and I p (Br p) orbital antibonding coupling and the high ionicity of CH3NH3PbX3 (X=I, Br). Secondly, we study the optoelectronic properties of Cu-V-VI earth abundant compounds. These low cost thin films may have the good electronic and optical properties. We have studied the structural, electronic and optical properties of Cu3-V-VI4 compounds. After testing four different crystal structures, enargite, wurtzite-PMCA, famatinite and zinc-blend-PMCA, we find that Cu3PS4 and Cu3PSe4 prefer energetically the enargite structure, whereas, other compounds favor the famatinite structure. Among the compounds and structures considered, enargite Cu3PSe4, and famatinite Cu3AsS4, are suitable for single junction solar cell applications due to bandgaps of 1.32 eV and 1.15 eV, respectively. Furthermore, CuSbS2 are also studied by density functional theory and HSE06 hybrid functional. The chalcostibite CuSbS2 has an indirect band gap of 1.85 eV, whereas the chalcogenide Cu3SbS4 has a direct band gap of 0.89 eV. We find that the large difference on band gaps is mainly attributed to the different Sb charge states. We further predict that the Sb charge states will affect the defect physics. Particularly, the Sb lone pair s orbitals in CuSbS2 have strong influence on the formation energies of Sb-related defects. Lastly, we have studied the atomic structure and electronic properties of aluminum (Al)-related defect complexes in silicon. We find a unique stable complex configuration consisting of an Ali and an oxygen dimer, Ali-2Oi, which introduces deep… Advisors/Committee Members: Yan, Yanfa (Advisor).

Subjects/Keywords: Physics; Perovskites solar cell, Density functional theory

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Shi, T. (2014). Optoelectronic and Defect Properties in Earth Abundant Photovoltaic Materials: First-principle Calculations. (Doctoral Dissertation). University of Toledo. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=toledo1418391935

Chicago Manual of Style (16^th Edition):

Shi, Tingting. “Optoelectronic and Defect Properties in Earth Abundant Photovoltaic Materials: First-principle Calculations.” 2014. Doctoral Dissertation, University of Toledo. Accessed February 27, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1418391935.

MLA Handbook (7^th Edition):

Shi, Tingting. “Optoelectronic and Defect Properties in Earth Abundant Photovoltaic Materials: First-principle Calculations.” 2014. Web. 27 Feb 2020.

Vancouver:

Shi T. Optoelectronic and Defect Properties in Earth Abundant Photovoltaic Materials: First-principle Calculations. [Internet] [Doctoral dissertation]. University of Toledo; 2014. [cited 2020 Feb 27]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=toledo1418391935.

Council of Science Editors:

Shi T. Optoelectronic and Defect Properties in Earth Abundant Photovoltaic Materials: First-principle Calculations. [Doctoral Dissertation]. University of Toledo; 2014. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=toledo1418391935

NSYSU

17. Chang, Ching-Sheng. A combination of Molecular dynamics, FIRE algorithm, and Density functional theory on structural and catalytic characteristics of Titania nanoparticle.

Degree: Master, Mechanical and Electro-Mechanical Engineering, 2008, NSYSU

URL: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0824108-215353

► In order to understand the structural and electronic properties of titanium oxide nanoparticles of different sizes, the FIRE algorithm combining the simulated annealing method is… (more)

Subjects/Keywords: Molecular Dynamics; Density functional theory; FIRE algorithm

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APA (6^th Edition):

Chang, C. (2008). A combination of Molecular dynamics, FIRE algorithm, and Density functional theory on structural and catalytic characteristics of Titania nanoparticle. (Thesis). NSYSU. Retrieved from http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0824108-215353

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Chang, Ching-Sheng. “A combination of Molecular dynamics, FIRE algorithm, and Density functional theory on structural and catalytic characteristics of Titania nanoparticle.” 2008. Thesis, NSYSU. Accessed February 27, 2020. http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0824108-215353.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Chang, Ching-Sheng. “A combination of Molecular dynamics, FIRE algorithm, and Density functional theory on structural and catalytic characteristics of Titania nanoparticle.” 2008. Web. 27 Feb 2020.

Vancouver:

Chang C. A combination of Molecular dynamics, FIRE algorithm, and Density functional theory on structural and catalytic characteristics of Titania nanoparticle. [Internet] [Thesis]. NSYSU; 2008. [cited 2020 Feb 27]. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0824108-215353.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Chang C. A combination of Molecular dynamics, FIRE algorithm, and Density functional theory on structural and catalytic characteristics of Titania nanoparticle. [Thesis]. NSYSU; 2008. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0824108-215353

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

NSYSU

18. Lin, Wen-huan. Decoupling of graphene from SiC(0001) surface by Au intercalation : A first-principles study.

Degree: Master, Physics, 2011, NSYSU

URL: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0214111-140556

► The atomic and electronic structures of Au-intercalated graphene buffer layer on SiC(0001) surface were investigated using first-principles calculations. The unique Dirac cone of the graphene… (more)

Subjects/Keywords: graphene; SiC; Dirac point; density functional theory

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APA (6^th Edition):

Lin, W. (2011). Decoupling of graphene from SiC(0001) surface by Au intercalation : A first-principles study. (Thesis). NSYSU. Retrieved from http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0214111-140556

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Lin, Wen-huan. “Decoupling of graphene from SiC(0001) surface by Au intercalation : A first-principles study.” 2011. Thesis, NSYSU. Accessed February 27, 2020. http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0214111-140556.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Lin, Wen-huan. “Decoupling of graphene from SiC(0001) surface by Au intercalation : A first-principles study.” 2011. Web. 27 Feb 2020.

Vancouver:

Lin W. Decoupling of graphene from SiC(0001) surface by Au intercalation : A first-principles study. [Internet] [Thesis]. NSYSU; 2011. [cited 2020 Feb 27]. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0214111-140556.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Lin W. Decoupling of graphene from SiC(0001) surface by Au intercalation : A first-principles study. [Thesis]. NSYSU; 2011. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0214111-140556

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Louisiana State University

19. Bae, Gyun-Tack. Computational studies of the properties of copper oxide clusters and the reactions of phenol and chlorinated phenols with copper oxide clusters.

Degree: PhD, Chemistry, 2009, Louisiana State University

URL: etd-11122009-113851 ; https://digitalcommons.lsu.edu/gradschool_dissertations/260

► We used ab initio simulations and calculations to study the structures and stabilities of copper oxide clusters, CunOn (n=1-8) and CuOn (n=1-6). The lowest energy… (more)

Subjects/Keywords: density functional theory; copper oxide clusters

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APA (6^th Edition):

Bae, G. (2009). Computational studies of the properties of copper oxide clusters and the reactions of phenol and chlorinated phenols with copper oxide clusters. (Doctoral Dissertation). Louisiana State University. Retrieved from etd-11122009-113851 ; https://digitalcommons.lsu.edu/gradschool_dissertations/260

Chicago Manual of Style (16^th Edition):

Bae, Gyun-Tack. “Computational studies of the properties of copper oxide clusters and the reactions of phenol and chlorinated phenols with copper oxide clusters.” 2009. Doctoral Dissertation, Louisiana State University. Accessed February 27, 2020. etd-11122009-113851 ; https://digitalcommons.lsu.edu/gradschool_dissertations/260.

MLA Handbook (7^th Edition):

Bae, Gyun-Tack. “Computational studies of the properties of copper oxide clusters and the reactions of phenol and chlorinated phenols with copper oxide clusters.” 2009. Web. 27 Feb 2020.

Vancouver:

Bae G. Computational studies of the properties of copper oxide clusters and the reactions of phenol and chlorinated phenols with copper oxide clusters. [Internet] [Doctoral dissertation]. Louisiana State University; 2009. [cited 2020 Feb 27]. Available from: etd-11122009-113851 ; https://digitalcommons.lsu.edu/gradschool_dissertations/260.

Council of Science Editors:

Bae G. Computational studies of the properties of copper oxide clusters and the reactions of phenol and chlorinated phenols with copper oxide clusters. [Doctoral Dissertation]. Louisiana State University; 2009. Available from: etd-11122009-113851 ; https://digitalcommons.lsu.edu/gradschool_dissertations/260

20. Witte, Jonathon Kendall. Development and Assessment of Electronic Structure Approaches for Non-Covalent Interactions.

Degree: Chemistry, 2017, University of California – Berkeley

URL: http://www.escholarship.org/uc/item/7mc3k8tm

► This thesis is primarily concerned with the development and assessment of electronic structure approaches for intermolecular interactions. Various aspects of existing approaches – most notably… (more)

Subjects/Keywords: Chemistry; Physics; density functional theory; electronic structure

10 more images…

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APA (6^th Edition):

Witte, J. K. (2017). Development and Assessment of Electronic Structure Approaches for Non-Covalent Interactions. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/7mc3k8tm

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Witte, Jonathon Kendall. “Development and Assessment of Electronic Structure Approaches for Non-Covalent Interactions.” 2017. Thesis, University of California – Berkeley. Accessed February 27, 2020. http://www.escholarship.org/uc/item/7mc3k8tm.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Witte, Jonathon Kendall. “Development and Assessment of Electronic Structure Approaches for Non-Covalent Interactions.” 2017. Web. 27 Feb 2020.

Vancouver:

Witte JK. Development and Assessment of Electronic Structure Approaches for Non-Covalent Interactions. [Internet] [Thesis]. University of California – Berkeley; 2017. [cited 2020 Feb 27]. Available from: http://www.escholarship.org/uc/item/7mc3k8tm.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Witte JK. Development and Assessment of Electronic Structure Approaches for Non-Covalent Interactions. [Thesis]. University of California – Berkeley; 2017. Available from: http://www.escholarship.org/uc/item/7mc3k8tm

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Virginia Tech

21. Fuhrer, Timothy J. Computational Study of the Properties and Stabilities of Endohedral Metallofullerenes.

Degree: PhD, Chemistry, 2013, Virginia Tech

URL: http://hdl.handle.net/10919/19344

► The chemistry of fullerenes, which are a class of carbon allotropes that can be prepared by vaporization of graphite in an electric arc in a… (more)

Subjects/Keywords: Fullerenes; Endohedral; Metallofullerenes; Density Functional Theory

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APA (6^th Edition):

Fuhrer, T. J. (2013). Computational Study of the Properties and Stabilities of Endohedral Metallofullerenes. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/19344

Chicago Manual of Style (16^th Edition):

Fuhrer, Timothy J. “Computational Study of the Properties and Stabilities of Endohedral Metallofullerenes.” 2013. Doctoral Dissertation, Virginia Tech. Accessed February 27, 2020. http://hdl.handle.net/10919/19344.

MLA Handbook (7^th Edition):

Fuhrer, Timothy J. “Computational Study of the Properties and Stabilities of Endohedral Metallofullerenes.” 2013. Web. 27 Feb 2020.

Vancouver:

Fuhrer TJ. Computational Study of the Properties and Stabilities of Endohedral Metallofullerenes. [Internet] [Doctoral dissertation]. Virginia Tech; 2013. [cited 2020 Feb 27]. Available from: http://hdl.handle.net/10919/19344.

Council of Science Editors:

Fuhrer TJ. Computational Study of the Properties and Stabilities of Endohedral Metallofullerenes. [Doctoral Dissertation]. Virginia Tech; 2013. Available from: http://hdl.handle.net/10919/19344

Virginia Tech

22. Li, Zheng. Accelerating Catalyst Discovery via Ab Initio Machine Learning.

Degree: PhD, Chemical Engineering, 2019, Virginia Tech

URL: http://hdl.handle.net/10919/95915

► Machine learning and deep learning techniques have revolutionized a range of industries in recent years and have huge potential to improve every aspect of our… (more)

▼ Machine learning and deep learning techniques have revolutionized a range of industries in recent years and have huge potential to improve every aspect of our daily lives. Essentially, machine-learning provides algorithms the ability to automatically discover the hidden patterns of data without being explicitly programmed. Because of this, machine learning models have gained huge successes in applications such as website recommendation systems, online fraud detection, robotic technologies, image recognition, etc. Nevertheless, implementing machine-learning techniques in the field of catalyst design remains difficult due to 2 primary challenges. The first challenge is our insufficient knowledge about the structure-property relationships for diverse material systems. Typically, developing a physically intuitive material feature method requests in-depth expert knowledge about the underlying physics of the material system and it is always an active field. The second challenge is the lack of training data in academic research. In many cases, collecting a sufficient amount of training data is not always feasible due to the limitation of computational/experimental resources. Subsequently, the machine learning model optimized with small data tends to be over-fitted and could provide biased predictions with huge uncertainties. To address the above-mentioned challenges, this thesis focus on the development of robust feature methods and strategies for a variety of catalyst systems using the density functional theory (DFT) calculations. Through the case studies in the chapters, we show that the bulk electronic structure characteristics are successful features for capturing the adsorption properties of metal alloys and metal oxides. While molecular graphs are robust features for the molecular property, e.g., energy gap, of metal-organics compounds. Besides, we demonstrate that the adaptive machine learning workflow is an effective strategy to tackle the data deficiency issue in search of perovskite catalysts for the oxygen evolution reaction. Advisors/Committee Members: Xin, Hongliang (committeechair), Achenie, Luke E. (committeechair), Deshmukh, Sanket A. (committee member), Morris, Amanda (committee member).

Subjects/Keywords: Computational catalysis; Density functional theory; Machine learning

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APA (6^th Edition):

Li, Z. (2019). Accelerating Catalyst Discovery via Ab Initio Machine Learning. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/95915

Chicago Manual of Style (16^th Edition):

Li, Zheng. “Accelerating Catalyst Discovery via Ab Initio Machine Learning.” 2019. Doctoral Dissertation, Virginia Tech. Accessed February 27, 2020. http://hdl.handle.net/10919/95915.

MLA Handbook (7^th Edition):

Li, Zheng. “Accelerating Catalyst Discovery via Ab Initio Machine Learning.” 2019. Web. 27 Feb 2020.

Vancouver:

Li Z. Accelerating Catalyst Discovery via Ab Initio Machine Learning. [Internet] [Doctoral dissertation]. Virginia Tech; 2019. [cited 2020 Feb 27]. Available from: http://hdl.handle.net/10919/95915.

Council of Science Editors:

Li Z. Accelerating Catalyst Discovery via Ab Initio Machine Learning. [Doctoral Dissertation]. Virginia Tech; 2019. Available from: http://hdl.handle.net/10919/95915

Cornell University

23. Letchworth Weaver, Kendra. Microscopically Detailed Joint Density-Functional Theory For The Electrode-Electrolyte Interface .

Degree: 2016, Cornell University

URL: http://hdl.handle.net/1813/43658

► Understanding the complex and inherently multi-scale interface between a charged electrode surface and a fluid electrolyte would inform design of more efficient and less costly… (more)

▼ Understanding the complex and inherently multi-scale interface between a charged electrode surface and a fluid electrolyte would inform design of more efficient and less costly electrochemical energy storage and conversion devices. Joint density-functional theory (JDFT) is an, in principle, exact theoretical framework which bridges the relevant length-scales by joining a fully ab initio description of the electrode with a highly efficient, yet atomically detailed classical DFT description of the liquid electrolyte structure. First, we introduce a universal approximate functional to couple any quantum- mechanical solute system with a classical DFT for any liquid and present classical density- functionals for both aqueous and non-aqueous fluids. This universal coupling functional predicts solvation energies of neutral molecules to within near-chemical accuracy of 1.5 kcal/mol and captures the qualitative and quantitative features of fluid correlation functions. We go on to explore the suitability of JDFT to describe electrochemical systems, reviewing the physics of the underlying fundamental electrochemical concepts and identifying the mapping between commonly measured electrochemical observables and microscopically computable quantities. We then introduce a simple, computationally efficient approximate functional which we find to be quite successful in capturing a priori basic electrochemical phenomena, includ- ing the capacitive Stern and diffusive Gouy-Chapman regions in the electrochemical double layer and potentials of zero charge for a series of metals. We also show that we are able to place our ab initio results directly on the scale associated with the Standard Hydrogen Electrode (SHE). Leveraging the above theoretical innovations, we then predict the voltagedependent structure and energetics of solvated ions at the interface between metal electrodes and an aqueous electrolyte, elucidating the origin of the nonlinear capacitance observed in electrochemical measurements. Finally, we discuss how JDFT calculations can determine the surface structure of a trained SrTiO3 surface under operating conditions for water-splitting and explore why this structure is correlated with higher activity than an untrained surface. We predict the specular X-ray crystal truncation rods for SrTiO3 , finding excellent agreement with experimental measurements from the Cornell High Energy Synchrotron Source (CHESS). Advisors/Committee Members: Wang,Michelle D (committeeMember), Sethna,James Patarasp (committeeMember).

Subjects/Keywords: Density-Functional Theory; Surface Chemistry; Applied Physics

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APA (6^th Edition):

Letchworth Weaver, K. (2016). Microscopically Detailed Joint Density-Functional Theory For The Electrode-Electrolyte Interface . (Thesis). Cornell University. Retrieved from http://hdl.handle.net/1813/43658

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Letchworth Weaver, Kendra. “Microscopically Detailed Joint Density-Functional Theory For The Electrode-Electrolyte Interface .” 2016. Thesis, Cornell University. Accessed February 27, 2020. http://hdl.handle.net/1813/43658.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Letchworth Weaver, Kendra. “Microscopically Detailed Joint Density-Functional Theory For The Electrode-Electrolyte Interface .” 2016. Web. 27 Feb 2020.

Vancouver:

Letchworth Weaver K. Microscopically Detailed Joint Density-Functional Theory For The Electrode-Electrolyte Interface . [Internet] [Thesis]. Cornell University; 2016. [cited 2020 Feb 27]. Available from: http://hdl.handle.net/1813/43658.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Letchworth Weaver K. Microscopically Detailed Joint Density-Functional Theory For The Electrode-Electrolyte Interface . [Thesis]. Cornell University; 2016. Available from: http://hdl.handle.net/1813/43658

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Cornell University

24. Gunceler, Deniz. Joint Density-Functional Theory For Energetics And Spectroscopy In Complex Aqueous And Nonaqueous Solvents .

Degree: 2016, Cornell University

URL: http://hdl.handle.net/1813/44292

► Solvents are of great importance in many technological applications, but are difficult to study using standard, off-the-shelf ab initio electronic structure methods. This is because… (more)

Subjects/Keywords: Density Functional Theory; Solvation; Electronic Structure

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APA (6^th Edition):

Gunceler, D. (2016). Joint Density-Functional Theory For Energetics And Spectroscopy In Complex Aqueous And Nonaqueous Solvents . (Thesis). Cornell University. Retrieved from http://hdl.handle.net/1813/44292

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Gunceler, Deniz. “Joint Density-Functional Theory For Energetics And Spectroscopy In Complex Aqueous And Nonaqueous Solvents .” 2016. Thesis, Cornell University. Accessed February 27, 2020. http://hdl.handle.net/1813/44292.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Gunceler, Deniz. “Joint Density-Functional Theory For Energetics And Spectroscopy In Complex Aqueous And Nonaqueous Solvents .” 2016. Web. 27 Feb 2020.

Vancouver:

Gunceler D. Joint Density-Functional Theory For Energetics And Spectroscopy In Complex Aqueous And Nonaqueous Solvents . [Internet] [Thesis]. Cornell University; 2016. [cited 2020 Feb 27]. Available from: http://hdl.handle.net/1813/44292.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Gunceler D. Joint Density-Functional Theory For Energetics And Spectroscopy In Complex Aqueous And Nonaqueous Solvents . [Thesis]. Cornell University; 2016. Available from: http://hdl.handle.net/1813/44292

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Cornell University

25. Zhuang, Houlong. Computational Discovery And Design Of Novel Single-Layer Materials For Electronic And Energy Applications .

Degree: 2014, Cornell University

URL: http://hdl.handle.net/1813/36085

► The last decade has seen an explosion of interest in two-dimensional materials, which now can be synthesized in either single or a few atomic layer… (more)

Subjects/Keywords: Single-layer materials; Density-functional theory; Semiconductors

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APA (6^th Edition):

Zhuang, H. (2014). Computational Discovery And Design Of Novel Single-Layer Materials For Electronic And Energy Applications . (Thesis). Cornell University. Retrieved from http://hdl.handle.net/1813/36085

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Zhuang, Houlong. “Computational Discovery And Design Of Novel Single-Layer Materials For Electronic And Energy Applications .” 2014. Thesis, Cornell University. Accessed February 27, 2020. http://hdl.handle.net/1813/36085.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Zhuang, Houlong. “Computational Discovery And Design Of Novel Single-Layer Materials For Electronic And Energy Applications .” 2014. Web. 27 Feb 2020.

Vancouver:

Zhuang H. Computational Discovery And Design Of Novel Single-Layer Materials For Electronic And Energy Applications . [Internet] [Thesis]. Cornell University; 2014. [cited 2020 Feb 27]. Available from: http://hdl.handle.net/1813/36085.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Zhuang H. Computational Discovery And Design Of Novel Single-Layer Materials For Electronic And Energy Applications . [Thesis]. Cornell University; 2014. Available from: http://hdl.handle.net/1813/36085

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Vanderbilt University

26. Driscoll, Joseph Andrew. Electron field emission in nanostructures: A first-principles study.

Degree: PhD, Physics, 2011, Vanderbilt University

URL: http://etd.library.vanderbilt.edu/available/etd-03152011-155603/ ;

► This dissertation presents the study of electron field emission from nanostructures using a first-principles computational framework. Field emission is studied under various conditions such as… (more)

▼ This dissertation presents the study of electron field emission from nanostructures using a first-principles computational framework. Field emission is studied under various conditions such as laser illumination, spin polarization, and the presence of adsorbates. Several nanostructures are considered (carbon nanowires, graphene nanoribbons, and nanotubes of varying composition) which allow general conclusions to be made. The calculations are performed using a real-space, real-time implementation of time-dependent density functional theory. In addition to field emission results, we also present rigorous evaluations of basis sets and complex absorbing potentials, both of which are needed in order to allow these demanding calculations to be performed efficiently. The best basis choice (e.g., atomic orbitals or real-space grids) depends on the structure of the system being analyzed and the physical processes involved (e.g., laser illumination). For this reason, it was important to conduct thorough tests of basis set performance, in terms of accuracy and computational efficiency. In non-periodic systems, emitted electron density can experience non-physical reflections from boundaries of the calculation volume, leading to inaccuracies. To prevent this, we used complex absorbing potentials (CAPs) to absorb density before it could reach the boundaries. We evaluate CAPs using test cases relevant to field emission calculations. Our results show that the adsorbate atoms studied significantly increase the field emission current of carbon nanotubes. We also show that short laser pulses can cause nanostructures to emit electrons with very high spatial and time resolutions. The results predict that GaN, SiC, and Si nanotubes are particularly good field emitters. The highest-current nanotube, Si, is predicted to produce currents an order of magnitude higher than BN or C nanotubes. Carbon nanotubes with various adsorbates are shown to be able to emit spin-polarized current. These are the first first-principles calculations showing spin-polarized field emission for carbon nanotubes with iron adsorbates. Finally, our results suggest that graphene nanoribbons could be extremely good field emitters. The results and computational methods discussed provide a foundation for future theoretical work in nanoscale field emission. Advisors/Committee Members: Sait Umar (committee member), Ronald Schrimpf (committee member), Sokrates Pantelides (committee member), Charles Brau (committee member), Kalman Varga (chair).

Subjects/Keywords: density functional theory; nanotubes; nanostructures; field emission

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APA (6^th Edition):

Driscoll, J. A. (2011). Electron field emission in nanostructures: A first-principles study. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://etd.library.vanderbilt.edu/available/etd-03152011-155603/ ;

Chicago Manual of Style (16^th Edition):

Driscoll, Joseph Andrew. “Electron field emission in nanostructures: A first-principles study.” 2011. Doctoral Dissertation, Vanderbilt University. Accessed February 27, 2020. http://etd.library.vanderbilt.edu/available/etd-03152011-155603/ ;.

MLA Handbook (7^th Edition):

Driscoll, Joseph Andrew. “Electron field emission in nanostructures: A first-principles study.” 2011. Web. 27 Feb 2020.

Vancouver:

Driscoll JA. Electron field emission in nanostructures: A first-principles study. [Internet] [Doctoral dissertation]. Vanderbilt University; 2011. [cited 2020 Feb 27]. Available from: http://etd.library.vanderbilt.edu/available/etd-03152011-155603/ ;.

Council of Science Editors:

Driscoll JA. Electron field emission in nanostructures: A first-principles study. [Doctoral Dissertation]. Vanderbilt University; 2011. Available from: http://etd.library.vanderbilt.edu/available/etd-03152011-155603/ ;

Vanderbilt University

27. Brock, Casey Neil. Automated Optimization of Pseudopotentials for Faster and More Accurate Plane Wave Density Functional Theory Calculations in Materials.

Degree: PhD, Interdisciplinary Materials Science, 2019, Vanderbilt University

URL: http://etd.library.vanderbilt.edu/available/etd-05162019-154431/ ;

► In principle, the properties of materials are determined by the behavior of electrons. Therefore quantum mechanical electronic structure calculations play a critical role in materials… (more)

Subjects/Keywords: pseudopotentials; density functional theory; electronic structure

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APA (6^th Edition):

Brock, C. N. (2019). Automated Optimization of Pseudopotentials for Faster and More Accurate Plane Wave Density Functional Theory Calculations in Materials. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://etd.library.vanderbilt.edu/available/etd-05162019-154431/ ;

Chicago Manual of Style (16^th Edition):

Brock, Casey Neil. “Automated Optimization of Pseudopotentials for Faster and More Accurate Plane Wave Density Functional Theory Calculations in Materials.” 2019. Doctoral Dissertation, Vanderbilt University. Accessed February 27, 2020. http://etd.library.vanderbilt.edu/available/etd-05162019-154431/ ;.

MLA Handbook (7^th Edition):

Brock, Casey Neil. “Automated Optimization of Pseudopotentials for Faster and More Accurate Plane Wave Density Functional Theory Calculations in Materials.” 2019. Web. 27 Feb 2020.

Vancouver:

Brock CN. Automated Optimization of Pseudopotentials for Faster and More Accurate Plane Wave Density Functional Theory Calculations in Materials. [Internet] [Doctoral dissertation]. Vanderbilt University; 2019. [cited 2020 Feb 27]. Available from: http://etd.library.vanderbilt.edu/available/etd-05162019-154431/ ;.

Council of Science Editors:

Brock CN. Automated Optimization of Pseudopotentials for Faster and More Accurate Plane Wave Density Functional Theory Calculations in Materials. [Doctoral Dissertation]. Vanderbilt University; 2019. Available from: http://etd.library.vanderbilt.edu/available/etd-05162019-154431/ ;

Université de Neuchâtel

28. Battaglia, Corsin. Structural and electronic properties of self-assembled nanostructures on silicon surfaces.

Degree: 2008, Université de Neuchâtel

URL: http://doc.rero.ch/record/9568

► Cette thèse présente de nouveaux résultats sur les nanostructures auto-assemblées sur surfaces de silicium étudiées par différentes techniques complémentaires: la microscopie et spectroscopie tunnel (STM/STS)… (more)

▼ Cette thèse présente de nouveaux résultats sur les nanostructures auto-assemblées sur surfaces de silicium étudiées par différentes techniques complémentaires: la microscopie et spectroscopie tunnel (STM/STS) à basse température, la diffraction dynamique d'électron de basse énergie (LEED), la spectroscopie de photoélectrons résolue en angle (ARPES) ainsi que des calculs "ab initio" réalisés dans le cadre de la théorie de la fonctionnelle de densité (DFT). A mesure que la taille des dispositifs électroniques, magnétiques et optiques s'approche du régime nanométrique, la compréhension des phénomènes quantiques présents sur les surfaces semiconductrices est de plus en plus importante pour la science et pour la technologie. Nous investiguons ici les propriétés structurales et électroniques à l'échelle atomique de la reconstruction Si(331)-(12£1), ainsi que des chaînes atomiques auto-assemblées sur la surface de Si(111). La surface de Si(331) est importante puisque c'est la seule surface plane de silicium qui présente une reconstruction stable avec une orientation comprise entre les directions (111) et (110). Après avoir optimisé la méthode de préparation de la surface, nous sommes désormais capables d'obtenir des régions de taille quasi micrométrique où l'arrangement atomique ne présente presque aucun défaut. Cette perfection sans précédent de la surface, combinée avec son anisotropie structurale prononcée, font de cette surface un candidat prometteur pour guider la croissance auto-assemblée de réseaux de nanostructures hétéro-épitaxiales. Depuis sa découverte datant de plus de 17 ans, plusieurs modèles structuraux ont été proposés. Cependant, aucun de ces modèles n'a été capable d'expliquer nos images STM à haute résolution. En exploitant la complémentarité de STM, LEED et DFT, nous proposons un nouveau modèle structural pour la reconstruction i(331)-(12£1) et discutons sa stabilité et ses propriétés électroniques. Nous nous focalisons ensuite sur les mécanismes sous-jacents de l'auto-assemblage des chaînes atomiques sur la surface de Si(111). Ces nanostructures ont suscité un énorme intérêt en raison de leurs propriétés électroniques quasi uni-dimensionnelles. En se basant sur la combinaison de nos études STM et LEED, nous proposons un nouveau modèle structural pour les chaînes atomiques induites par le Gd. Nous concluons qu'outre les adsorbats mono- et divalents, les adsorbats trivalents sont aussi capables de stabiliser des chaînes atomiques. Ceci établit les chaînes constituées de silicium du type "honeycomb" et "Seiwatz" comme blocs de construction universels dans les reconstructions de chaîne atomiques induites par les adsorbats. La systèmatique dans l'auto-assemblage est expliquée en reliant l'état de valence de l'adsorbat aux symétries accessibles des chaînes. Nous examinons encore théoriquement la stabilité des différentes phases de chaînes en utilisant des méthodes de calculs de structure électronique "ab initio" et comparons nos résultats aux expériences. Advisors/Committee Members: Philipp (Dir.).

Subjects/Keywords: density functional theory

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APA (6^th Edition):

Battaglia, C. (2008). Structural and electronic properties of self-assembled nanostructures on silicon surfaces. (Thesis). Université de Neuchâtel. Retrieved from http://doc.rero.ch/record/9568

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Battaglia, Corsin. “Structural and electronic properties of self-assembled nanostructures on silicon surfaces.” 2008. Thesis, Université de Neuchâtel. Accessed February 27, 2020. http://doc.rero.ch/record/9568.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Battaglia, Corsin. “Structural and electronic properties of self-assembled nanostructures on silicon surfaces.” 2008. Web. 27 Feb 2020.

Vancouver:

Battaglia C. Structural and electronic properties of self-assembled nanostructures on silicon surfaces. [Internet] [Thesis]. Université de Neuchâtel; 2008. [cited 2020 Feb 27]. Available from: http://doc.rero.ch/record/9568.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Battaglia C. Structural and electronic properties of self-assembled nanostructures on silicon surfaces. [Thesis]. Université de Neuchâtel; 2008. Available from: http://doc.rero.ch/record/9568

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Texas – Austin

29. -6008-5857. Advanced modeling for end-of-the-roadmap CMOS and potential beyond-CMOS applications.

Degree: PhD, Electrical and Computer engineering, 2016, University of Texas – Austin

URL: http://hdl.handle.net/2152/40264

► End-of-the-roadmap CMOS devices are explored via particle-based ensemble semi-classical Monte Carlo (MC) methods employing quantum corrections (QCs) to address quantum confinement and degenerate carrier populations.… (more)

▼ End-of-the-roadmap CMOS devices are explored via particle-based ensemble semi-classical Monte Carlo (MC) methods employing quantum corrections (QCs) to address quantum confinement and degenerate carrier populations. The significance of such QCs is illustrated through simulation of n-channel III-V and Si FinFETs. Original contributions include our treatment of far-from-equilibrium degenerate statistics and QC-based modeling of surface-roughness scattering, as well as considering quantum-confined phonon and ionized-impurity scattering in 3D. Typical MC simulations approximate degenerate carrier populations as Fermi distributions to model the Pauli-blocking (PB) of scattering to occupied final states. To allow for increasingly far-from-equilibrium non-Fermi carrier distributions in ultra-scaled and III-V devices, we instead generate the final-state occupation probabilities used for PB by sampling the local carrier populations as a function of energy and energy valley. This process is aided by the use of fractional carriers or sub-carriers, which minimizes classical carrier-carrier scattering. Quantum confinement effects are addressed through quantum-correction potentials (QCPs) generated from coupled Schrödinger-Poisson solvers, as commonly done. However, we use our valley- and orientation-dependent QCPs not just to redistribute carriers in real space, or even among energy valleys, but also to calculate confinement-dependent phonon, ionized-impurity, and surface-roughness scattering rates. Collectively, these quantum effects can substantially reduce and even eliminate otherwise expected benefits of considered InGaAs FinFETs over otherwise identical Si FinFETs, despite higher thermal velocities in InGaAs. Beyond-CMOS device concepts are also being considered for future applications. Thin-film sub-5 nm magnetic skyrmions constitute an ultimate scaling alternative for beyond-CMOS data storage technologies. These robust non-collinear spin-textures can be moved and manipulated by spin-polarized or non-spin-polarized electrical currents, which is extremely attractive for integration with current memory technologies. An innovative technique to detect isolated nano-skyrmions with a current-perpendicular-to-plane is shown, which has immediate implications for device concepts. Such a mechanism is explored by studying the atomistic electronic structure of the magnetic quasiparticles. The tunneling conductance is quite sensitive to spatial variations in the electronic structure, as a large atomistic conductance anisotropy up to 20 is found for magnetic skyrmions in Pd/Fe/Ir(111) magnetic thin-films. This spin-mixing magnetoresistance effect possibly could be incorporated in future magnetic storage technologies. Advisors/Committee Members: Register, Leonard F. (advisor), Banerjee, Sanjay K (committee member), Tutuc, Emanuel (committee member), Lee, Jack C (committee member), MacDonald, Allan H (committee member).

Subjects/Keywords: FinFETs; Skyrmions; Monte Carlo; Density-functional theory

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APA (6^th Edition):

-6008-5857. (2016). Advanced modeling for end-of-the-roadmap CMOS and potential beyond-CMOS applications. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/40264

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Author name may be incomplete

Chicago Manual of Style (16^th Edition):

-6008-5857. “Advanced modeling for end-of-the-roadmap CMOS and potential beyond-CMOS applications.” 2016. Doctoral Dissertation, University of Texas – Austin. Accessed February 27, 2020. http://hdl.handle.net/2152/40264.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

MLA Handbook (7^th Edition):

-6008-5857. “Advanced modeling for end-of-the-roadmap CMOS and potential beyond-CMOS applications.” 2016. Web. 27 Feb 2020.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Vancouver:

-6008-5857. Advanced modeling for end-of-the-roadmap CMOS and potential beyond-CMOS applications. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2016. [cited 2020 Feb 27]. Available from: http://hdl.handle.net/2152/40264.

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

Council of Science Editors:

-6008-5857. Advanced modeling for end-of-the-roadmap CMOS and potential beyond-CMOS applications. [Doctoral Dissertation]. University of Texas – Austin; 2016. Available from: http://hdl.handle.net/2152/40264

Note: this citation may be lacking information needed for this citation format:
Author name may be incomplete

University of New South Wales

30. Huang, Bosi. DFT study of tungstates for photocatalytic water splitting.

Degree: Materials Science & Engineering, 2019, University of New South Wales

URL: http://handle.unsw.edu.au/1959.4/64868

► Photocatalytic and photoelectrochemical water splitting can play an important role in future renewable energy systems by allowing solar energy to be stored in the form… (more)

▼ Photocatalytic and photoelectrochemical water splitting can play an important role in future renewable energy systems by allowing solar energy to be stored in the form of hydrogen. Tungsten oxide (WO3) has some promising properties as a photocatalytic material, but as a simple binary oxide, is has limitations on its optoelectronic properties. In order to improve the visible-light absorption efficiency for photocatalytic applications, the band gap should be further reduced. Moving to ternary compounds can be a strategic method to achieve this, as ternary compounds provide a much greater variety in compositions and hence properties. In this work, the effect of introducing a second metal cation into tungsten oxide is studied by Density Functional Theory (DFT) calculations using the HSE06 functional. The compounds investigated include AWO4 tungstates (A = Sn, Fe), M2WO6 tungstates (M = Bi, Sb), tungstite (WO3·H2O) and hydrotungstite (WO3·2H2O). The band gaps are found to be 2.98 eV (WO3), 1.65 eV (SnWO4), 2.03 eV (FeWO4), 2.83 eV (Bi2WO6), 2.91 eV (Sb2WO6), 2.27 eV (WO3·H2O), 2.51 eV (WO3·2H2O). The band gaps of all the tungstates studied in this work are lower than that of binary WO3. The valence bands of these ternary oxides are formed by the oxygen 2p orbitals and the s orbitals of the second metal cations, which contribute to the band gap narrowing compared to WO3. Structural properties are also strongly correlated with the band energies; the spacing between layers of WO6 octahedra was found to be related to the conduction band edge, with larger spacing causing a shift in the band edge to a more negative potential compared to WO3. The tungstates studied are found to have either a small band gap (SnWO4, FeWO4, WO3·H2O and WO3·2H2O), and hence can potentially give a high efficiency for visible-light absorption, or a more negative conduction band edge than WO3 (Bi2WO6, Sb2WO6), which means they may be able to achieve the overall water splitting. The defect properties of several intrinsic defects in α-SnWO4 are also evaluated; a SnW antisite defect and oxygen vacancy (VO) are found to be the most two probable defects to form in α-SnWO4. Furthermore, SnW defects may lead to an enhancement of the photocatalytic performance under sunlight, while VO are expected to decrease the performance. Advisors/Committee Members: Hart, Judy, Materials Science & Engineering, Faculty of Science, UNSW.

Subjects/Keywords: Density functional theory; Tungstates; Photocatalytic water splitting

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Huang, B. (2019). DFT study of tungstates for photocatalytic water splitting. (Masters Thesis). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/64868

Chicago Manual of Style (16^th Edition):

Huang, Bosi. “DFT study of tungstates for photocatalytic water splitting.” 2019. Masters Thesis, University of New South Wales. Accessed February 27, 2020. http://handle.unsw.edu.au/1959.4/64868.

MLA Handbook (7^th Edition):

Huang, Bosi. “DFT study of tungstates for photocatalytic water splitting.” 2019. Web. 27 Feb 2020.

Vancouver:

Huang B. DFT study of tungstates for photocatalytic water splitting. [Internet] [Masters thesis]. University of New South Wales; 2019. [cited 2020 Feb 27]. Available from: http://handle.unsw.edu.au/1959.4/64868.

Council of Science Editors:

Huang B. DFT study of tungstates for photocatalytic water splitting. [Masters Thesis]. University of New South Wales; 2019. Available from: http://handle.unsw.edu.au/1959.4/64868

Open Access Theses and Dissertations