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1.
Timian, Eric.
Relativistic Multireference Perturbation Theory With Applications To D And F Block Metal Systems.
Degree: PhD, Chemistry, 2018, University of North Dakota
URL: https://commons.und.edu/theses/2365
► Electronic structure theory programs strive to be as widely applicable as possible. In order to account for effects exhibited by heavier elements, relativistic considerations…
(more)
▼ Electronic structure theory programs strive to be as widely applicable as possible. In order to account for effects exhibited by heavier elements, relativistic considerations must be incorporated into these programs. The methods developed in recent years generally succeed in describing the relativistic nature of systems containing heavier elements with reasonable accuracy, but have limited application due to their complexity and computational demand. Highly correlated systems exhibiting significant relativistic effects remain as a challenge to quantum chemical methods.
In this thesis, I present the application of a well-defined relativistic Hamiltonian to a high-level electronic structure theory to generate a relativistic variant of a high-level
multireference electronic structure theory capable of obtaining accurate results for highly correlated relativistic systems. This theory applies the exact two-component (X2C) relativistic Hamiltonian and a third-order Douglass-Kroll-Hess (DKH3) transformation for the spin-free and spin-orbit terms, respectively. The spin-orbit integrals are contracted into an effective one-electron Hamiltonian using the atomic mean field (AMFI) approximation, which increases computational efficiency with little loss in accuracy. By applying this scheme to the second-order generalized van Vleck perturbation theory (GVVPT2), which offers appropriate treatment of electron correlation, a theory providing an accurate analysis of chemical systems with strong relativistic effects is obtained.
The method developed in this work is used to explore ground and low-lying excited states of the lanthanide dimer systems Gd2 and Dy2. Results from scalar relativistic studies show that GVVPT2 can accurately characterize these systems. The ground electronic states obtained (Gd2: 19Σg- ; Dy2: 11Î g) match literature and theoretical results. The spectroscopic data obtained for the ground state of Gd2 (Re = 2.826 Ã
; De = 2.48 eV; Ïe = 153.0 cm-1) are in excellent agreement with literature values (Re = 2.877 Ã
; D0 = 2.1 ± 0.7 eV; Ïe = 138-149 cm-1). Inclusion of spin-orbit coupling in these studies is expected to improve the results to agree with literature values to within chemical accuracy. Future work is planned to extend this method to transition metal trimers.
Advisors/Committee Members: Mark Hoffmann.
Subjects/Keywords: Chemistry; Dimer; Lanthanide; Multireference; Perturbation Theory; Relativistic
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APA (6th Edition):
Timian, E. (2018). Relativistic Multireference Perturbation Theory With Applications To D And F Block Metal Systems. (Doctoral Dissertation). University of North Dakota. Retrieved from https://commons.und.edu/theses/2365
Chicago Manual of Style (16th Edition):
Timian, Eric. “Relativistic Multireference Perturbation Theory With Applications To D And F Block Metal Systems.” 2018. Doctoral Dissertation, University of North Dakota. Accessed April 18, 2021.
https://commons.und.edu/theses/2365.
MLA Handbook (7th Edition):
Timian, Eric. “Relativistic Multireference Perturbation Theory With Applications To D And F Block Metal Systems.” 2018. Web. 18 Apr 2021.
Vancouver:
Timian E. Relativistic Multireference Perturbation Theory With Applications To D And F Block Metal Systems. [Internet] [Doctoral dissertation]. University of North Dakota; 2018. [cited 2021 Apr 18].
Available from: https://commons.und.edu/theses/2365.
Council of Science Editors:
Timian E. Relativistic Multireference Perturbation Theory With Applications To D And F Block Metal Systems. [Doctoral Dissertation]. University of North Dakota; 2018. Available from: https://commons.und.edu/theses/2365

Princeton University
2.
Taffet, Elliot.
Unmasking Underlying Molecular Photophysical Mechanisms Using Quantum Chemistry
.
Degree: PhD, 2019, Princeton University
URL: http://arks.princeton.edu/ark:/88435/dsp017w62fc131
► Quantum chemistry is performed on biological chromophores in light harvesting and synthetic chromophores in targeted photochemical applications to elucidate how molecular electronic structure impacts their…
(more)
▼ Quantum chemistry is performed on biological chromophores in light harvesting and synthetic chromophores in targeted photochemical applications to elucidate how molecular electronic structure impacts their underlying function. This function is revealed to manifest from the interplay between light-absorbing bright states and light- transmitting dark electronic excited states. The role played by these states, representing either different spatial or different spin symmetries, is discerned using
multireference perturbation theory methodologies. Through these methods, molecular mechanisms of spin manipulation underlying the photophysical complexity observed in experimental spectroscopy are unveiled. These mechanisms hinge on correlations entangling pairs of spin-triplet eigenfunctions or spin-orbit coupling connecting formally spin singlet and spin triplet states. The former is unveiled to be the key intermediate initiator for multiplying molecular charge production from light, while the latter is unveiled to be the key driving force for multiplying light production from charges initiated by electrical stimulation. These processes are simulated at the molecular level using nonadiabatic dynamics that tracks electronic population transfer between states driven by nuclear motion in time. The dynamics are directed by couplings that may be modulated through definable nuclear distortion traceable to the activation of specific vibrational degrees of freedom. These computed vibrationally-assisted electronic dynamics across model molecular systems enable the discrimination between intrinsic intramolecular photophysics and the effects of the surrounding molecular environment in naturally- occurring supramolecular pigment-protein complexes or device active layers.
Advisors/Committee Members: Scholes, Gregory D (advisor).
Subjects/Keywords: exchange;
fission;
fluorescence;
multireference;
photophysics;
spectroscopy
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APA ·
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APA (6th Edition):
Taffet, E. (2019). Unmasking Underlying Molecular Photophysical Mechanisms Using Quantum Chemistry
. (Doctoral Dissertation). Princeton University. Retrieved from http://arks.princeton.edu/ark:/88435/dsp017w62fc131
Chicago Manual of Style (16th Edition):
Taffet, Elliot. “Unmasking Underlying Molecular Photophysical Mechanisms Using Quantum Chemistry
.” 2019. Doctoral Dissertation, Princeton University. Accessed April 18, 2021.
http://arks.princeton.edu/ark:/88435/dsp017w62fc131.
MLA Handbook (7th Edition):
Taffet, Elliot. “Unmasking Underlying Molecular Photophysical Mechanisms Using Quantum Chemistry
.” 2019. Web. 18 Apr 2021.
Vancouver:
Taffet E. Unmasking Underlying Molecular Photophysical Mechanisms Using Quantum Chemistry
. [Internet] [Doctoral dissertation]. Princeton University; 2019. [cited 2021 Apr 18].
Available from: http://arks.princeton.edu/ark:/88435/dsp017w62fc131.
Council of Science Editors:
Taffet E. Unmasking Underlying Molecular Photophysical Mechanisms Using Quantum Chemistry
. [Doctoral Dissertation]. Princeton University; 2019. Available from: http://arks.princeton.edu/ark:/88435/dsp017w62fc131
3.
Hicks, Jason M.
Computational Studies Of Oxides Relevant To Clean Energy, Catalytic Processing Of Renewables, And Biological Systems.
Degree: PhD, Chemistry, 2018, University of North Dakota
URL: https://commons.und.edu/theses/2232
► Computational chemistry has grown into a large field and is continuing to grow every year in both number and variety of applications. This dissertation…
(more)
▼ Computational chemistry has grown into a large field and is continuing to grow every year in both number and variety of applications. This dissertation will give a few such applications relevant to cleaner energy production from coal, catalytic degradation of renewable agricultural and forest waste into valuable chemicals, and extending the reach of electronic structure methods to systems of biological and macromolecular interest. The first two studies presented in this dissertation are concerned with the remediation of trace elements released into the environment through the combustion of coal for power production. In flue gases, arsenic and antimony exists most often as oxides. Despite the prevalence and importance of remediating these oxides, critical information on the thermodynamics of plausible intermediates and transition states in reaction pathways have been missing prior to these studies. Several of the intermediates, and essentially all transition states, were found to be electronically multiconfigurational for the arsenic oxides. In this work, the electronic structures of several oxides of arsenic, AsxOy, where x = 1, 2 and y = 1-5, were investigated using the second-order generalized van Vleck variant of
multireference perturbation theory (GVVPT2), using the cc-pVTZ basis set, with comparison to multi-reference configuration interaction (MRCISD) and the linked completely renormalized coupled cluster through perturbative triple excitations (CR-CCSD(T)L or CR-CC(2,3)) when relevant. Calculated oxidation reaction energies for the formation of AsO2 and AsO3 from AsO were predicted to be energetically favorable and formation energies of the lowest energy compounds containing two metalloid atoms, called dimers for brevity, from the monomers were also predicted to be energetically favorable. The energetics of the monomers, five isomers of As2O3 and eleven isomers of As2O5 were characterized using a composite methodology along with the key transition states between the isomers. Geometry optimizations as well as harmonic vibrational frequencies of AsxOy were obtained at the B3LYP/6-311G* level of theory and gave satisfactory agreement with experimental data when available. It was discovered that several isomers of As2O3 and As2O5 have comparable energies and relatively low barrier heights. Therefore, we expect these isomers to be chemically relevant.
The antimony oxides were also found to be electronically multiconfigurational. The electronic structures of several antimony oxides, SbxOy, where x = 1, 2 and y = 1-5, were investigated using GVVPT2 and the SBD-aug-cc-pVTZ basis set. The oxidation reaction energies of elemental antimony toward the formation of SbO and SbO2 was found to be energetically favorable, while the further oxidation of those species to SbO3 was found to be unfavorable. It was found that the accretion of the monomers into Sb2O3 was highly energetically favorable at both the B3LYP/SBD-aug-cc-pVTZ and GVVPT2/SBD-aug-cc-pVTZ//B3LYP/SBD-aug-cc-pVTZ levels of theory. However,…
Advisors/Committee Members: Mark R. Hoffmann.
Subjects/Keywords: Cu2O2; electronic structure theory; GVVPT2; lignin; metalloid oxides; multireference perturbation theory
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Hicks, J. M. (2018). Computational Studies Of Oxides Relevant To Clean Energy, Catalytic Processing Of Renewables, And Biological Systems. (Doctoral Dissertation). University of North Dakota. Retrieved from https://commons.und.edu/theses/2232
Chicago Manual of Style (16th Edition):
Hicks, Jason M. “Computational Studies Of Oxides Relevant To Clean Energy, Catalytic Processing Of Renewables, And Biological Systems.” 2018. Doctoral Dissertation, University of North Dakota. Accessed April 18, 2021.
https://commons.und.edu/theses/2232.
MLA Handbook (7th Edition):
Hicks, Jason M. “Computational Studies Of Oxides Relevant To Clean Energy, Catalytic Processing Of Renewables, And Biological Systems.” 2018. Web. 18 Apr 2021.
Vancouver:
Hicks JM. Computational Studies Of Oxides Relevant To Clean Energy, Catalytic Processing Of Renewables, And Biological Systems. [Internet] [Doctoral dissertation]. University of North Dakota; 2018. [cited 2021 Apr 18].
Available from: https://commons.und.edu/theses/2232.
Council of Science Editors:
Hicks JM. Computational Studies Of Oxides Relevant To Clean Energy, Catalytic Processing Of Renewables, And Biological Systems. [Doctoral Dissertation]. University of North Dakota; 2018. Available from: https://commons.und.edu/theses/2232
4.
Li, Run.
Theory And Application Development Of Electronic Structure Methods Involving Heavy Computation.
Degree: PhD, Chemistry, 2017, University of North Dakota
URL: https://commons.und.edu/theses/2269
► The propargyl radical, the most stable isomer of C3H3, is very important in combustion reactions. However, theoretical calculations have never been able to find…
(more)
▼ The propargyl radical, the most stable isomer of C3H3, is very important in combustion reactions. However, theoretical calculations have never been able to find a strong absorption around 242 nm as seen in experiments. In this study, we calculated the electronic energy levels of the propargyl radical using highly accurate
multireference methods, including
multireference configuration interaction singles and doubles method with triples and quadruples treated perturbatively [denoted as MRCISD(TQ)], as well as second and third order generalized Van Vleck perturbation theories (GVVPT2 and GVVPT3). Calculations indicate that this absorption can be solely attributed to a Franck-Condon-allowed transition from the ground B1 state to the Rydberg-like first A1 excited state. Calculations also show that GVVPT2 with a relatively small active space fails to capture enough Rydberg character of this excited state, while it can be recovered by GVVPT3, MRCISD, and MRCISD(TQ).
In order to speed up MRCISD(TQ) calculations, the triple and quadruple (TQ) perturbative corrections, the most time-consuming part of MRCISD(TQ) calculations, were parallelized using Message Passing Interface (MPI). The MRCISD(TQ) method is organized in the framework of macroconfigurations, which allows the use of incomplete reference spaces and provides an efficient means of screening large number of non-interacting configuration state functions (CSFs). The test calculations show that the parallel code achieved close to linear speed-up when the number of CSFs in each macroconfiguration is small. The speed-up suffers when large numbers of CSFs exist in only a few macroconfigurations.
The computer algorithm for second-order generalized van Vleck
multireference perturbation theory (GVVPT2) was similarly parallelized using the MPI protocol, organized in the framework of macroconfigurations. The maximum number of CSFs per macroconfiguration is found to have less influence on the MPI speedup and scaling than in the case of MRCISD(TQ).
It was previously found that unrestricted local density approximation (LDA) orbitals can be used in place of MCSCF to provide orbitals for GVVPT2. This inspired us to use the more controllable restricted density functional theory (DFT) to provide unbiased orbitals for GVVPT2 calculations. In this study, the relationship between restricted DFT and unrestricted DFT were explored and the restricted DFT results were obtained by utilizing subroutines from unrestricted DFT calculations. We also found that the DIIS technique drastically sped up the convergence of RDFT calculations.
Plane wave DFT methods are commonly used to efficiently evaluate solid state materials. In this work, the electronic properties of pristine graphene and Zn-phthalocyanine tetrasulfonic acid (Zn-PcS) physisorbed on single-layer graphene were calculated using plane wave DFT. The Perdew-Burke-Ernzerhof functional with dispersion correction (PBE-D2) was used. The densities of states were…
Advisors/Committee Members: Mark R. Hoffmann.
Subjects/Keywords: electronic structure theory; GVVPT2; MPI; MRCISD(TQ); multireference perturbation theory; parallelization
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Li, R. (2017). Theory And Application Development Of Electronic Structure Methods Involving Heavy Computation. (Doctoral Dissertation). University of North Dakota. Retrieved from https://commons.und.edu/theses/2269
Chicago Manual of Style (16th Edition):
Li, Run. “Theory And Application Development Of Electronic Structure Methods Involving Heavy Computation.” 2017. Doctoral Dissertation, University of North Dakota. Accessed April 18, 2021.
https://commons.und.edu/theses/2269.
MLA Handbook (7th Edition):
Li, Run. “Theory And Application Development Of Electronic Structure Methods Involving Heavy Computation.” 2017. Web. 18 Apr 2021.
Vancouver:
Li R. Theory And Application Development Of Electronic Structure Methods Involving Heavy Computation. [Internet] [Doctoral dissertation]. University of North Dakota; 2017. [cited 2021 Apr 18].
Available from: https://commons.und.edu/theses/2269.
Council of Science Editors:
Li R. Theory And Application Development Of Electronic Structure Methods Involving Heavy Computation. [Doctoral Dissertation]. University of North Dakota; 2017. Available from: https://commons.und.edu/theses/2269

University of Waterloo
5.
Huntington, Lee Michael.
Development of an Automatic Code Generator and Implementation of Multireference Equation of Motion Coupled-Cluster Theory in the ORCA Program Package.
Degree: 2015, University of Waterloo
URL: http://hdl.handle.net/10012/9778
► Over the past 50 years, single-reference coupled-cluster theory has emerged as a cornerstone of quantum chemistry. While it is an accurate methodology for the calculation…
(more)
▼ Over the past 50 years, single-reference coupled-cluster theory has emerged as a cornerstone of quantum chemistry. While it is an accurate methodology for the calculation of the properties of the electronic states of many systems, there are still many strongly-correlated (multireference) systems which cannot be adequately treated with single-reference coupled-cluster theory. Hence, in the past four decades, there have been significant efforts to develop multireference generalizations of coupled-cluster theory to treat such systems. In this work, we review some of the major developments in single-reference and multireference molecular electronic structure theory. We discuss the details of the Multireference Equation of Motion (MR-EOM) coupled-cluster approach, developed in the Nooijen group, and introduce a new variant which makes use of a Hermitizing transformation. The MR-EOM methodology constitutes a transform and diagonalize approach to electronic structure theory, that is applicable to both ground and excited states. A major topic of this thesis concerns the development of an automatic code generation tool, that has been used to implement the MR-EOM approach in the ORCA quantum chemistry software package. The implementation in ORCA is employed for the characterization and calculation of the excitation energies of transition metal complexes. We also introduce an orbital selection scheme which can be used to extend the applicability of the MR-EOM approach to larger systems for the calculation of excitation spectra. A variety of MR-EOM approaches are then considered in benchmark applications to organic molecules and the various approximations, introduced in the ORCA implementation of MR-EOM, are studied for several transition metal complexes. Finally, we discuss how the implementation in ORCA might be improved in the future, in order to push applications to larger systems and larger active spaces.
Subjects/Keywords: Coupled-Cluster Theory; Excited States; Multireference Coupled-Cluster; Automatic Code Generation
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APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Huntington, L. M. (2015). Development of an Automatic Code Generator and Implementation of Multireference Equation of Motion Coupled-Cluster Theory in the ORCA Program Package. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/9778
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Huntington, Lee Michael. “Development of an Automatic Code Generator and Implementation of Multireference Equation of Motion Coupled-Cluster Theory in the ORCA Program Package.” 2015. Thesis, University of Waterloo. Accessed April 18, 2021.
http://hdl.handle.net/10012/9778.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Huntington, Lee Michael. “Development of an Automatic Code Generator and Implementation of Multireference Equation of Motion Coupled-Cluster Theory in the ORCA Program Package.” 2015. Web. 18 Apr 2021.
Vancouver:
Huntington LM. Development of an Automatic Code Generator and Implementation of Multireference Equation of Motion Coupled-Cluster Theory in the ORCA Program Package. [Internet] [Thesis]. University of Waterloo; 2015. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/10012/9778.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Huntington LM. Development of an Automatic Code Generator and Implementation of Multireference Equation of Motion Coupled-Cluster Theory in the ORCA Program Package. [Thesis]. University of Waterloo; 2015. Available from: http://hdl.handle.net/10012/9778
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Georgia
6.
Evangelista, Francesco.
Multireference coupled cluster theory.
Degree: 2014, University of Georgia
URL: http://hdl.handle.net/10724/25175
► In this dissertation we have developed and applied the state specific multireference coupled cluster theory suggested by Mukherjee and co workers (Mk-MRCC). For model systems,…
(more)
▼ In this dissertation we have developed and applied the state specific multireference coupled cluster theory suggested by Mukherjee and co workers (Mk-MRCC). For model systems, Mk-MRCC is found to provide more accurate results than competitor
theories at all levels of truncation of the cluster operator. The first production level code for Mukherjee multireference coupled cluster singles and doubles (Mk-MRCCSD) computations has been written. A crucial element for the development of Mk-MRCC
into a computational tool was the realization that the coupling terms appearing in the equations could be written in a simple closed form. Mk-MRCCSD results are reported for the singlet triplet splittings in ortho-, meta-, and para-benzyne, coming within
1.5 kcal/mol of experiment in all cases. We also report the first implementation with correct scaling of the Mk-MRCC method with singles, doubles, and approximate iterative triples Mk-MRCCSDT-n, (n = 1a,1b,2,3) as well as full triples (Mk-MRCCSDT). In
all model systems the various Mk-MRCCSDT-n approaches recover on average between 59% and 73% of the full triples effect.
Subjects/Keywords: coupled cluster theory; multireference; open-shell; diradical; benzyne
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APA ·
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MLA ·
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APA (6th Edition):
Evangelista, F. (2014). Multireference coupled cluster theory. (Thesis). University of Georgia. Retrieved from http://hdl.handle.net/10724/25175
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Evangelista, Francesco. “Multireference coupled cluster theory.” 2014. Thesis, University of Georgia. Accessed April 18, 2021.
http://hdl.handle.net/10724/25175.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Evangelista, Francesco. “Multireference coupled cluster theory.” 2014. Web. 18 Apr 2021.
Vancouver:
Evangelista F. Multireference coupled cluster theory. [Internet] [Thesis]. University of Georgia; 2014. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/10724/25175.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Evangelista F. Multireference coupled cluster theory. [Thesis]. University of Georgia; 2014. Available from: http://hdl.handle.net/10724/25175
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Waterloo
7.
Yao, Jingfei.
The Electronic Structures of Cobalt-containing Diatomic Molecules.
Degree: 2016, University of Waterloo
URL: http://hdl.handle.net/10012/10958
► Theoretical investigations of the electronic structures of several metal-containing diatomic species (i.e., Co2+, Co+•RG (RG=He, Ar, Kr), Au+Ar, and Ag+Ar) have been conducted. In this…
(more)
▼ Theoretical investigations of the electronic structures of several metal-containing diatomic species (i.e., Co2+, Co+•RG (RG=He, Ar, Kr), Au+Ar, and Ag+Ar) have been conducted. In this study, two categories of methods have been utilized for the calculations: single reference methods, including density functional theory (DFT, TD-DFT) and coupled cluster theory (CCSD, EOM- CCSD), and multireference methods, such as multireference configuration interaction (MRCI) and multireference equation-of-motion coupled cluster theory (MREOM-CCSD).
Preliminary results for the potential energy curves (PBEs) of Co2+ as calculated with DFT and EOM-CCSD yields two anomalous results: discontinuous PECs and negative excitation energies. These two results indicate that single reference methods are not adequate for description of the Co2+ system, and that multireference methods should be employed. MRCI calculations which employed the Davidson correction remedied the negative excitation energies issue, but the PECs remained discontinuous at this level of theory. The MREOM-CCSD method produced exclusively positive excitation energies and continuous PECs. The dissociation thresholds (D0) for the ground states of Co+•Ar, Co+•Kr, Ag+•Ar, and Au+•Ar were calculated to be 0.3872 eV, 0.5443 eV, 0.1931 eV, and 0.3696 eV, respectively by MREOM-T|T+|SXD/Def2-TZVPPD. These calculations included corrections for spin-orbit coupling (SOC), basis set superposition error (BSSE), and zero- point energy (ZPE). However, the theoretically calculated dissociation thresholds of Co+•Ar and Co+•Kr are approximately 0.11 eV lower than the experimentally determined values of 0.5097 eV and 0.6701 eV, respectively. These discrepancies could due to the unsuitable selection of the complete active space (CAS) and/or the basis set in the calculation, or the validity of the experimental measurement.
Subjects/Keywords: Multireference Configuration Interaction (MRCI); Multireference Equation-of-Motion Coupled Cluster Theory (MREOM-CC); Potential Energy Curves (PECs); Cobalt Cation with Rare Gas
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Yao, J. (2016). The Electronic Structures of Cobalt-containing Diatomic Molecules. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/10958
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Yao, Jingfei. “The Electronic Structures of Cobalt-containing Diatomic Molecules.” 2016. Thesis, University of Waterloo. Accessed April 18, 2021.
http://hdl.handle.net/10012/10958.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Yao, Jingfei. “The Electronic Structures of Cobalt-containing Diatomic Molecules.” 2016. Web. 18 Apr 2021.
Vancouver:
Yao J. The Electronic Structures of Cobalt-containing Diatomic Molecules. [Internet] [Thesis]. University of Waterloo; 2016. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/10012/10958.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Yao J. The Electronic Structures of Cobalt-containing Diatomic Molecules. [Thesis]. University of Waterloo; 2016. Available from: http://hdl.handle.net/10012/10958
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Princeton University
8.
Morais Carreira Pereira, Joao.
Information theoretic aspects of cryo-electron microscopy
.
Degree: PhD, 2019, Princeton University
URL: http://arks.princeton.edu/ark:/88435/dsp01rj430743n
► In the problem of single particle reconstruction in cryo-electron microscopy (cryo-EM), we want to recover the 3D electrostatic potential of a molecule from noisy 2D…
(more)
▼ In the problem of single particle reconstruction in cryo-electron microscopy (cryo-EM), we want to recover the 3D electrostatic potential of a molecule from noisy 2D projections along unknown random viewing directions. A similar problem is multi-reference alignment (MRA), where we want to recover a signal from noisy circularly shifted copies, and the circular shifts are also unknown.
This thesis focuses on the sample complexity of these problems, that is, the number of observations required for signal estimation, as a function of the noise level, in the regime of large number of observations and high level of noise; this is the prevalent regime in cryo-EM. In this regime, the sample complexity is determined by the moments of the observations, thus we present various applications of the method of moments in MRA and cryo-EM.
Motivated by the tensor structure of higher order moments, we also develop a novel algorithm for symmetric even-order tensor decomposition.
Advisors/Committee Members: Singer, Amit (advisor), Abbe, Emmanuel (advisor).
Subjects/Keywords: Cryo-electron microscopy;
information theory;
method of moments;
multireference alignment;
sample complexity;
tensor decomposition
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Morais Carreira Pereira, J. (2019). Information theoretic aspects of cryo-electron microscopy
. (Doctoral Dissertation). Princeton University. Retrieved from http://arks.princeton.edu/ark:/88435/dsp01rj430743n
Chicago Manual of Style (16th Edition):
Morais Carreira Pereira, Joao. “Information theoretic aspects of cryo-electron microscopy
.” 2019. Doctoral Dissertation, Princeton University. Accessed April 18, 2021.
http://arks.princeton.edu/ark:/88435/dsp01rj430743n.
MLA Handbook (7th Edition):
Morais Carreira Pereira, Joao. “Information theoretic aspects of cryo-electron microscopy
.” 2019. Web. 18 Apr 2021.
Vancouver:
Morais Carreira Pereira J. Information theoretic aspects of cryo-electron microscopy
. [Internet] [Doctoral dissertation]. Princeton University; 2019. [cited 2021 Apr 18].
Available from: http://arks.princeton.edu/ark:/88435/dsp01rj430743n.
Council of Science Editors:
Morais Carreira Pereira J. Information theoretic aspects of cryo-electron microscopy
. [Doctoral Dissertation]. Princeton University; 2019. Available from: http://arks.princeton.edu/ark:/88435/dsp01rj430743n

Princeton University
9.
Morais Carreira Pereira, Joao.
Information theoretic aspects of cryo-electron microscopy
.
Degree: PhD, 2019, Princeton University
URL: http://arks.princeton.edu/ark:/88435/dsp019s1619052
► In the problem of single particle reconstruction in cryo-electron microscopy (cryo-EM), we want to recover the 3D electrostatic potential of a molecule from noisy 2D…
(more)
▼ In the problem of single particle reconstruction in cryo-electron microscopy (cryo-EM), we want to recover the 3D electrostatic potential of a molecule from noisy 2D projections along unknown random viewing directions. A similar problem is multi-reference alignment (MRA), where we want to recover a signal from noisy circularly shifted copies, and the circular shifts are also unknown.
This thesis focuses on the sample complexity of these problems, that is, the number of observations required for signal estimation, as a function of the noise level, in the regime of large number of observations and high level of noise; this is the prevalent regime in cryo-EM. In this regime, the sample complexity is determined by the moments of the observations, thus we present various applications of the method of moments in MRA and cryo-EM.
Motivated by the tensor structure of higher order moments, we also develop a novel algorithm for symmetric even-order tensor decomposition.
Advisors/Committee Members: Singer, Amit (advisor), Abbe, Emmanuel (advisor).
Subjects/Keywords: Cryo-electron microscopy;
information theory;
method of moments;
multireference alignment;
sample complexity;
tensor decomposition
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Morais Carreira Pereira, J. (2019). Information theoretic aspects of cryo-electron microscopy
. (Doctoral Dissertation). Princeton University. Retrieved from http://arks.princeton.edu/ark:/88435/dsp019s1619052
Chicago Manual of Style (16th Edition):
Morais Carreira Pereira, Joao. “Information theoretic aspects of cryo-electron microscopy
.” 2019. Doctoral Dissertation, Princeton University. Accessed April 18, 2021.
http://arks.princeton.edu/ark:/88435/dsp019s1619052.
MLA Handbook (7th Edition):
Morais Carreira Pereira, Joao. “Information theoretic aspects of cryo-electron microscopy
.” 2019. Web. 18 Apr 2021.
Vancouver:
Morais Carreira Pereira J. Information theoretic aspects of cryo-electron microscopy
. [Internet] [Doctoral dissertation]. Princeton University; 2019. [cited 2021 Apr 18].
Available from: http://arks.princeton.edu/ark:/88435/dsp019s1619052.
Council of Science Editors:
Morais Carreira Pereira J. Information theoretic aspects of cryo-electron microscopy
. [Doctoral Dissertation]. Princeton University; 2019. Available from: http://arks.princeton.edu/ark:/88435/dsp019s1619052

University of Georgia
10.
Vaughn, Alexander Edward.
Applications of multireference coupled cluster theory.
Degree: 2014, University of Georgia
URL: http://hdl.handle.net/10724/30687
► In this work, Mukherjee multireference and single reference coupled cluster theory has been applied to the cyclobutanetetraone and trimethylene systems. Computations performed on cyclobutanetetraone have…
(more)
▼ In this work, Mukherjee multireference and single reference coupled cluster theory has been applied to the cyclobutanetetraone and trimethylene systems. Computations performed on cyclobutanetetraone have found that while the molecule appears
to be just another simple, closed-shell molecule, it in fact has at least four low‐lying electronic states with D4h symmetry (Zhou, X.; Hrovat, D. A.; Borden, W. T. J. Phys. Chem. A 2010, 114, 1304). These include an all-symmetric state with eight
π-electrons, a open-shell singlet and a triplet state with nine π-electrons, and an all-symmetric state with ten π-electrons. In this work, Mk-MRCCSD and CCSD(T) geometry optimizations with a cc-pVQZ basis have been executed for the low-lying states.
These states are spread over 5.95 kcal/mol based upon the focal point approach. A recent photoelectron study (Guo, J.-C.; Hou, G.-L.; Li, S.-D.; Wang, X.-B. J. Phys. Chem. Lett. 2012, 3, 304) of the cyclobutanetetraone anion reported term values of 1.50
± 0.1 and 3.23 ± 0.1 kcal mol–1 for the 8π all-symmetric and the 9π singlet open-shell states of neutral cyclobutanetetraone respectively; however, our computations indicate that the 10π all-symmetric state lies below the 9π open-shell singlet state. In
contrast, the 9π triplet ground state is predicted to lie 4.34 kcal/mol below the 8π all-symmetric state, and the 10π all-symmetric state 1.00 kcal/mol above the 8π all-symmetric state. The trimethylene diradical is involved in the thermal isomerization
of cyclopropane and the isomerization to propene. The transition states (2, C2v) and (3, Cs) for the isomerization of cyclopropane possess substantial static and dynamical electron correlation, and thus has been optimized with the Mk‐MRCCSD(T) method.
Upon which focal point analyses of the barrier height to isomerization of cyclopropane have been performed. Their character was investigated by computing vibrational frequencies, which have imaginary frequencies corresponding to the conrotatory and
disrotatory motions for (2) and (3) respectively, at the Mk-MRPT2 and Mk-MRCCSD levels of theory with the cc-pVDZ basis set. Focal point analyses of the vertical excitation energy of the transition states found that a seam of crossing occurs near the C2v
edge-to-edge transition state (2).
Subjects/Keywords: multireference coupled cluster theory; thermochemistry; cyclobutanetetraone; cyclopropane; unusual triplet ground state; Hund’s Rule; intersystem crossing
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Vaughn, A. E. (2014). Applications of multireference coupled cluster theory. (Thesis). University of Georgia. Retrieved from http://hdl.handle.net/10724/30687
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Vaughn, Alexander Edward. “Applications of multireference coupled cluster theory.” 2014. Thesis, University of Georgia. Accessed April 18, 2021.
http://hdl.handle.net/10724/30687.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Vaughn, Alexander Edward. “Applications of multireference coupled cluster theory.” 2014. Web. 18 Apr 2021.
Vancouver:
Vaughn AE. Applications of multireference coupled cluster theory. [Internet] [Thesis]. University of Georgia; 2014. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/10724/30687.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Vaughn AE. Applications of multireference coupled cluster theory. [Thesis]. University of Georgia; 2014. Available from: http://hdl.handle.net/10724/30687
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Bowling Green State University
11.
Borin, Veniamin Aleksandrovich.
A Computational Study of Diiodomethane
Photoisomerization.
Degree: PhD, Photochemical Sciences, 2016, Bowling Green State University
URL: http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1477581227858711
► This work gives the detailed description of the dynamics and mechanism of the previouslyunsuspected photochemical reaction path of diiodomethane (CH2I2), a paradigmatic haloalkane,which is direct…
(more)
▼ This work gives the detailed description of the
dynamics and mechanism of the previouslyunsuspected photochemical
reaction path of diiodomethane (CH2I2), a paradigmatic
haloalkane,which is direct intramolecular isomerization upon the
excitation of this molecule to the lowestsinglet S1 state. The
previous liquid-phase ultrafast spectroscopy experiments on the
UVphotochemistry of di- and polyhalomethanes suggest that following
excitation of these molecules,the carbon-halogen bond breaks,
leading to formation of the initial radical pair. The radical
pair,trapped by a solvent cage collapses into an isomer product
species with halogen-halogen bond ona picoseconds timescale (1 ps =
10-12 s). Yet, the results recently obtained in our research
group,clearly suggest that in addition to this conventional,
in-cage isomerization process, there is another,unconventional
isomerization mechanism, which occurs on a sub-100 fs timescale (1
fs = 10-15 s)and does not require the solvent environment around
the excited CH2I2 solute. Indeed, the ultrafastsub-100 fs timescale
observed suggests two main considerations:• The sub-100 fs
photoisomerization in polyhalomethanes is direct, i.e. proceeds via
theintramolecular reaction mechanism proceeding without any
intermediates (such as a radicalpair) and, likely, is mediated by a
crossing of excited and ground electronic states.• The solvent cage
may not be needed, because the timescale of the
aforementionedisomerization process is shorter than the 100-200 fs
timescale for a single collisionalencounter between solvent and
solute molecules.iiiFemtosecond transient absorption spectroscopy
is a very valuable tool in studying thephotochemical reactivity on
short timescales. The measured ultrafast time-resolved spectra
arecomplicated by relaxation processes in far from equilibrium
solutes, such as intramolecular energyredistribution and flow, and
can be understood in detail with the help from
state-of-the-artquantum-chemical modeling. Thus, in order to gain
the detailed interpretation of the observed(photo)chemical dynamics
it is necessary to complement the femtosecond experiments with
themodern quantum-chemical computations.
Advisors/Committee Members: Tarnovsky, Alexander (Advisor), Olivucci, Massimo (Committee Co-Chair).
Subjects/Keywords: Chemistry; Physics; CASPT2; Multireference methods; Computational chemistry; Diiodomethane; Resonance structures; Molecular dynamics
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Borin, V. A. (2016). A Computational Study of Diiodomethane
Photoisomerization. (Doctoral Dissertation). Bowling Green State University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1477581227858711
Chicago Manual of Style (16th Edition):
Borin, Veniamin Aleksandrovich. “A Computational Study of Diiodomethane
Photoisomerization.” 2016. Doctoral Dissertation, Bowling Green State University. Accessed April 18, 2021.
http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1477581227858711.
MLA Handbook (7th Edition):
Borin, Veniamin Aleksandrovich. “A Computational Study of Diiodomethane
Photoisomerization.” 2016. Web. 18 Apr 2021.
Vancouver:
Borin VA. A Computational Study of Diiodomethane
Photoisomerization. [Internet] [Doctoral dissertation]. Bowling Green State University; 2016. [cited 2021 Apr 18].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1477581227858711.
Council of Science Editors:
Borin VA. A Computational Study of Diiodomethane
Photoisomerization. [Doctoral Dissertation]. Bowling Green State University; 2016. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1477581227858711

University of Waterloo
12.
Wu, Siyuan.
Investigations of Magnetic Model Systems Using Coupled Cluster Based Approaches.
Degree: 2017, University of Waterloo
URL: http://hdl.handle.net/10012/12186
► Over the past decades, the quantum mechanical description of magnetic phenomena has been well developed. However, the first principle calculations of the physical properties of…
(more)
▼ Over the past decades, the quantum mechanical description of magnetic phenomena has been well developed. However, the first principle calculations of the physical properties of magnetic systems is still a challenge. One solution to the problem is to construct model magnetic Hamiltonians such that these Hamiltonians can well describe accurate energies of the low-lying magnetic states, starting from an ab initio Hamiltonian in a finite atomic orbital basis set.
In the first part of this work, the multireference equation of motion coupled cluster (MREOM-CC) approach including spin-orbit coupling is applied to model magnetic systems FArO, FArOF and FArFOH. All low-lying magnetic states are obtained subsequently from a compact diagonalization of the transformed Hamiltonian in the MREOM-CC scheme. The accuracy of MREOM is shown to be comparable to the well-established multireference Configuration Interaction with singles and doubles and the Davidson Q correction (MRCISD+Q), but the MREOM approach is significantly more efficient for systems with a large number of electronic states.
In the second part, we discuss the details of the effective Hamiltonian approach, proposed in this work. The purpose of this approach is to obtain low-lying states for a Hamiltonian that consists of pairwise interactions between magnetic sites only. The approach includes two steps: the definition of an effective Hamiltonian that acts in a compact space of low-lying single-site states obtained from a mean-field calculation, and the diagonalization of the effective Hamiltonian. The last step still limits the size of systems that can be tackled. Some variants of the effective Hamiltonian approach are tested in benchmark applications to model magnetic systems. The results indicate that this approach is promising, and finally we briefly discuss how this approach can be improved in the near future.
Subjects/Keywords: Model magnetic Hamiltonians; Multireference equation of motion coupled cluster (MREOM-CC); Spin-orbit coupling; Effective Hamiltonian approach
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Wu, S. (2017). Investigations of Magnetic Model Systems Using Coupled Cluster Based Approaches. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/12186
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Wu, Siyuan. “Investigations of Magnetic Model Systems Using Coupled Cluster Based Approaches.” 2017. Thesis, University of Waterloo. Accessed April 18, 2021.
http://hdl.handle.net/10012/12186.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Wu, Siyuan. “Investigations of Magnetic Model Systems Using Coupled Cluster Based Approaches.” 2017. Web. 18 Apr 2021.
Vancouver:
Wu S. Investigations of Magnetic Model Systems Using Coupled Cluster Based Approaches. [Internet] [Thesis]. University of Waterloo; 2017. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/10012/12186.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Wu S. Investigations of Magnetic Model Systems Using Coupled Cluster Based Approaches. [Thesis]. University of Waterloo; 2017. Available from: http://hdl.handle.net/10012/12186
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Georgia
13.
Magers, David Brandon.
Overcoming three theoretical challenges in high accuracy ab initio electronic structure theory.
Degree: 2014, University of Georgia
URL: http://hdl.handle.net/10724/30534
► Modern ab initio electronic theory provides an accurate method to compute molecular properties of subchemical accuracy. Despite recent advances and developments, many challenges arise that…
(more)
▼ Modern ab initio electronic theory provides an accurate method to compute molecular properties of subchemical accuracy. Despite recent advances and developments, many challenges arise that require special treatment for particular systems and
properties. Here three theoretical challenges are addressed. First, the need of a high accuracy multireference method is discussed to properly describe radical-radical abstraction reactions in chemical combustion. Second, a warning is given against
black-box computations by documenting anomalous imaginary frequencies in common planar and linear systems when post-Hartree-Fock methods are applied with insufficient basis sets. Third, an analysis is provided to quantify the qualitative concept of
intramolecular dispersion by examining individual pair correlation energies.
Subjects/Keywords: coupled cluster theory; multireference coupled cluster theory; Møller-Plesset theory; basis set extrapolation; focal point analysis
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Magers, D. B. (2014). Overcoming three theoretical challenges in high accuracy ab initio electronic structure theory. (Thesis). University of Georgia. Retrieved from http://hdl.handle.net/10724/30534
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Magers, David Brandon. “Overcoming three theoretical challenges in high accuracy ab initio electronic structure theory.” 2014. Thesis, University of Georgia. Accessed April 18, 2021.
http://hdl.handle.net/10724/30534.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Magers, David Brandon. “Overcoming three theoretical challenges in high accuracy ab initio electronic structure theory.” 2014. Web. 18 Apr 2021.
Vancouver:
Magers DB. Overcoming three theoretical challenges in high accuracy ab initio electronic structure theory. [Internet] [Thesis]. University of Georgia; 2014. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/10724/30534.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Magers DB. Overcoming three theoretical challenges in high accuracy ab initio electronic structure theory. [Thesis]. University of Georgia; 2014. Available from: http://hdl.handle.net/10724/30534
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Johannes Gutenberg Universität Mainz
14.
Prochnow, Eric.
New developments in state-specific multireference coupled-cluster theory.
Degree: 2010, Johannes Gutenberg Universität Mainz
URL: http://ubm.opus.hbz-nrw.de/volltexte/2010/2446/
► Coupled-cluster theory in its single-reference formulation represents one of the most successful approaches in quantum chemistry for the description of atoms and molecules. To extend…
(more)
▼ Coupled-cluster theory in its single-reference formulation represents one of the most successful approaches in quantum chemistry for the description of atoms and molecules. To extend the applicability of single-reference coupled-cluster theory to systems with degenerate or near-degenerate electronic configurations, multireference coupled-cluster methods have been suggested. One of the most promising formulations of multireference coupled cluster theory is the state-specific variant suggested by Mukherjee and co-workers (Mk-MRCC). Unlike other multireference coupled-cluster approaches, Mk-MRCC is a size-extensive theory and results obtained so far indicate that it has the potential to develop to a standard tool for high-accuracy quantum-chemical treatments. This work deals with developments to overcome the limitations in the applicability of the Mk-MRCC method. Therefore, an efficient Mk-MRCC algorithm has been implemented in the CFOUR program package to perform energy calculations within the singles and doubles (Mk-MRCCSD) and singles, doubles, and triples (Mk-MRCCSDT) approximations. This implementation exploits the special structure of the Mk-MRCC working equations that allows to adapt existing efficient single-reference coupled-cluster codes. The algorithm has the correct computational scaling of d*N6 for Mk-MRCCSD and d*N8 for Mk-MRCCSDT, where N denotes the system size and d the number of reference determinants. For the determination of molecular properties as the equilibrium geometry, the theory of analytic first derivatives of the energy for the Mk-MRCC method has been developed using a Lagrange formalism. The Mk-MRCC gradients within the CCSD and CCSDT approximation have been implemented and their applicability has been demonstrated for various compounds such as 2,6-pyridyne, the 2,6-pyridyne cation, m-benzyne, ozone and cyclobutadiene. The development of analytic gradients for Mk-MRCC offers the possibility of routinely locating minima and transition states on the potential energy surface. It can be considered as a key step towards routine investigation of multireference systems and calculation of their properties. As the full inclusion of triple excitations in Mk-MRCC energy calculations is computational demanding, a parallel implementation is presented in order to circumvent limitations due to the required execution time. The proposed scheme is based on the adaption of a highly efficient serial Mk-MRCCSDT code by parallelizing the time-determining steps. A first application to 2,6-pyridyne is presented to demonstrate the efficiency of the current implementation.
Die Coupled-Cluster-Theorie basierend auf einer Slater-Determinante als Referenz ist eine der erfolgreichsten Ansätze in der Quantenchemie zur Beschreibung von Atomen und Molekülen. Um deren Anwendbarkeit auf Systeme mit entarteten oder quasientarteten Elektronenkonfigurationen zu erweitern, wurden sogenannte Multireferenz-Coupled-Cluster-Ansätze entwickelt, die mehr als eine Referenzdeterminante verwenden. Eine der vielversprechendsten…
Subjects/Keywords: Quantenchemie, Mukherjee Multireferenz-Coupled-Cluster, Analytische Gradienten, Parallelisierung, Biradikale; quantum chemistry, Mukherjee multireference coupled-cluster, analytic gradients, parallelization, biradicals; Chemistry and allied sciences
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Prochnow, E. (2010). New developments in state-specific multireference coupled-cluster theory. (Doctoral Dissertation). Johannes Gutenberg Universität Mainz. Retrieved from http://ubm.opus.hbz-nrw.de/volltexte/2010/2446/
Chicago Manual of Style (16th Edition):
Prochnow, Eric. “New developments in state-specific multireference coupled-cluster theory.” 2010. Doctoral Dissertation, Johannes Gutenberg Universität Mainz. Accessed April 18, 2021.
http://ubm.opus.hbz-nrw.de/volltexte/2010/2446/.
MLA Handbook (7th Edition):
Prochnow, Eric. “New developments in state-specific multireference coupled-cluster theory.” 2010. Web. 18 Apr 2021.
Vancouver:
Prochnow E. New developments in state-specific multireference coupled-cluster theory. [Internet] [Doctoral dissertation]. Johannes Gutenberg Universität Mainz; 2010. [cited 2021 Apr 18].
Available from: http://ubm.opus.hbz-nrw.de/volltexte/2010/2446/.
Council of Science Editors:
Prochnow E. New developments in state-specific multireference coupled-cluster theory. [Doctoral Dissertation]. Johannes Gutenberg Universität Mainz; 2010. Available from: http://ubm.opus.hbz-nrw.de/volltexte/2010/2446/

Johannes Gutenberg Universität Mainz
15.
Hanauer, Matthias.
Internally contracted multireference coupled-cluster methods.
Degree: 2013, Johannes Gutenberg Universität Mainz
URL: http://ubm.opus.hbz-nrw.de/volltexte/2013/3423/
► This thesis details the development of quantum chemical methods for the accurate theoretical description of molecular systems with a complicated electronic structure. In simple cases,…
(more)
▼ This thesis details the development of quantum chemical methods for the accurate theoretical description of molecular systems with a complicated electronic structure. In simple cases, a single Slater determinant, in which the electrons occupy a number of energetically lowest molecular orbitals, offers a qualitatively correct model. The widely used coupled-cluster method CCSD(T) efficiently includes electron correlation effects starting from this determinant and provides reaction energies in error by only a few kJ/mol. However, the method often fails when several electronic configurations are important, as, for instance, in the course of many chemical reactions or in transition metal compounds. Internally contracted multireference coupled-cluster methods (ic-MRCC methods) cure this deficiency by using a linear combination of determinants as a reference function. Despite their theoretical elegance, the ic-MRCC equations involve thousands of terms and are therefore derived by the computer. Calculations of energy surfaces of BeH2, HF, LiF, H2O, N2 and Be3 unveil the theory's high accuracy compared to other approaches and the quality of various hierarchies of approximations. New theoretical advances include size-extensive techniques for removing linear dependencies in the ic-MRCC equations and a multireference analog of CCSD(T). Applications of the latter method to O3, Ni2O2, benzynes, C6H7NO and Cr2 underscore its potential to become a new standard method in quantum chemistry.
Diese Dissertation erläutert die Entwicklung quantenchemischer Methoden zur genauen theoretischen Beschreibung molekularer Systeme mit komplizierter elektronischer Struktur. In einfachen Fällen bietet eine Slaterdeterminante, in der die Elektronen eine Anzahl energetisch niedrigster Orbitale besetzen, ein qualitativ korrektes Modell. Die weitverbreitete Coupled-Cluster-Methode CCSD(T) berücksichtigt effizient Elektronenkorrelationseffekte ausgehend von dieser Determinante und liefert Reaktionsenergien mit Fehlern im Bereich weniger kJ/mol. Die Methode versagt allerdings häufig, wenn mehrere Elektronenkonfigurationen wichtig sind, wie zum Beispiel im Verlauf vieler chemischer Reaktionen oder in Übergangsmetallverbindungen. Intern kontrahierte Multireferenz-Coupled-Cluster-Methoden (ic-MRCC-Methoden) beheben dieses Defizit durch Verwendung einer Linearkombination von Determinanten als Referenzfunktion. Trotz ihrer theoretischen Eleganz beinhalten die ic-MRCC-Gleichungen Tausende von Termen und werden daher mit dem Computer hergeleitet. Berechnungen der Energieflächen von BeH2, HF, LiF, H2O, N2 and Be3 enthüllen die hohe Genauigkeit der Theorie im Vergleich zu anderen Ansätzen und die Qualität diverser Hierarchien von Näherungen. Neue theoretische Fortschritte umfassen größenextensive Techniken zur Beseitigung linearer Abhängigkeiten in den ic-MRCC-Gleichungen und ein Multireferenz-Analogon zu CCSD(T). Anwendungen der letztgenannten Methode auf die Moleküle O3, Ni2O2, Didehydrobenzole, C6H7NO and Cr2 unterstreichen ihr Potenzial, eine neue…
Subjects/Keywords: Quantenchemie; elektronische Struktur; Coupled-Cluster-Theorie; Multireferenz; Übergangsmetallverbindungen; quantum chemistry; electronic structure; coupled-cluster theory; multireference; transition metal compounds; Chemistry and allied sciences
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Hanauer, M. (2013). Internally contracted multireference coupled-cluster methods. (Doctoral Dissertation). Johannes Gutenberg Universität Mainz. Retrieved from http://ubm.opus.hbz-nrw.de/volltexte/2013/3423/
Chicago Manual of Style (16th Edition):
Hanauer, Matthias. “Internally contracted multireference coupled-cluster methods.” 2013. Doctoral Dissertation, Johannes Gutenberg Universität Mainz. Accessed April 18, 2021.
http://ubm.opus.hbz-nrw.de/volltexte/2013/3423/.
MLA Handbook (7th Edition):
Hanauer, Matthias. “Internally contracted multireference coupled-cluster methods.” 2013. Web. 18 Apr 2021.
Vancouver:
Hanauer M. Internally contracted multireference coupled-cluster methods. [Internet] [Doctoral dissertation]. Johannes Gutenberg Universität Mainz; 2013. [cited 2021 Apr 18].
Available from: http://ubm.opus.hbz-nrw.de/volltexte/2013/3423/.
Council of Science Editors:
Hanauer M. Internally contracted multireference coupled-cluster methods. [Doctoral Dissertation]. Johannes Gutenberg Universität Mainz; 2013. Available from: http://ubm.opus.hbz-nrw.de/volltexte/2013/3423/

University of Georgia
16.
DeYonker, Nathan J.
Transition-metals and excited states.
Degree: 2014, University of Georgia
URL: http://hdl.handle.net/10724/22336
► Two sets of molecular isomers, the iron monoisocyanide (FeNC) / iron monocyanide (FeCN) pair, and the hydroboron monoxide (HBO) / boron hydroxide (BOH) pair, are…
(more)
▼ Two sets of molecular isomers, the iron monoisocyanide (FeNC) / iron monocyanide (FeCN) pair, and the hydroboron monoxide (HBO) / boron hydroxide (BOH) pair, are investigated with a variety of high-level ab initio techniques. The electronic
structure of the FeNC and FeCN pair does not easily succumb to the coupled cluster ansatz, even when newly developed correlation-consistent polarized valence iron basis sets and inclusion of perturbative or partial iterative triple excitations are
included in the wave function. Due to disparities between the one-electron properties obtained with multireference configuration interaction (MRCI) and coupled cluster methods, the coupled cluster wave function could be considered inapplicable, at least
at the currently tractable coupled cluster excitation level. On the contrary, the accuracy of linear and bent ground state BOH MRCI geometries, dipole moments, and harmonic frequencies are spectacularly poor with a full valence active space, while
coupled cluster methods perform well. Using a new variant of the equation-of-motion coupled cluster (EOM-CC) method to include partial triple excitations within excited state wave functions, seven linear and nine bent excited states of HBO and BOH are
characterized. Adiabatic and vertical transition energies of low-lying BOH states will guide an experimental hypothesis that BOH, which has not yet been synthesized in any form, may be a suitable high energy-density material.
Subjects/Keywords: ab initio quantum chemistry; equation-of-motion coupled cluster; coupled cluster; multireference configuration interaction; transition metals; iron cyanide; FeNC; FeCN; boron hydroxide; BOH; HBO; excited electronic state
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APA ·
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APA (6th Edition):
DeYonker, N. J. (2014). Transition-metals and excited states. (Thesis). University of Georgia. Retrieved from http://hdl.handle.net/10724/22336
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
DeYonker, Nathan J. “Transition-metals and excited states.” 2014. Thesis, University of Georgia. Accessed April 18, 2021.
http://hdl.handle.net/10724/22336.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
DeYonker, Nathan J. “Transition-metals and excited states.” 2014. Web. 18 Apr 2021.
Vancouver:
DeYonker NJ. Transition-metals and excited states. [Internet] [Thesis]. University of Georgia; 2014. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/10724/22336.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
DeYonker NJ. Transition-metals and excited states. [Thesis]. University of Georgia; 2014. Available from: http://hdl.handle.net/10724/22336
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
17.
Canfora, Rosanna.
Patient sujet dans l'institution : observation et comparaison franco-italiennes. Pratiques de le rencontre anti-institutionnelle Entre Basaglia et Tosquelles : The patient as subject in the institution : examination and comparison of France and Italy.
Degree: Docteur es, Psychologie. Recherches en psychanalyse et psychopatologie, 2018, Sorbonne Paris Cité
URL: http://www.theses.fr/2018USPCC059
► L’idée qui traverse l’ensemble de la thèse est la possibilité de la rencontre de deux mouvements : Psichiatria democratica et la psychothérapie institutionnelle, de deux…
(more)
▼ L’idée qui traverse l’ensemble de la thèse est la possibilité de la rencontre de deux mouvements : Psichiatria democratica et la psychothérapie institutionnelle, de deux psychiatres Basaglia et Tosquelles, rencontre entre médecin et patient ; rencontre entre patient psychotique et le monde, monde étant compris comme la société mais aussi le groupe de soin.La réflexion est basée sur des points « d’accrochage » entre différents discours : psychanalytique, historique, sociologique, philosophique ou phénoménologique à travers un axe central : celui de la relation possible entre médecin et patient au-delà d’une logique institutionnelle close. La pratique de la rencontre, à travers leurs protagonistes : opérateurs, usagers, patients etc… Ne peut, de fait, être comprise qu’à travers les concepts qui la fondent : l’inconscient, le transfert, la pulsion, etc. Elle est, comme on l’entendra ici, un rencontre transférentielle lieu de relations interpersonnelles qui doivent savoir s’adapter à la singularité de chacun.
The main theory of the thesis is the possibility of two psychiatrical movements meeting at a crossroad: Italian "psichiatria democratica" and French "psychothérapie institutionnelle". In the study their two founders, the psychiatrists Basaglia and Tosquelles are compared as well as the relation between psychiatrist and patient and patient and world (as society but also as group of care). The observation is focused on common grounds among different disciplines, psychoanalytic, historical, sociological, philosophical and phenomenological, over a central axis: the relationship between physician and patient outside the logic of closed institutional clinics. The setting of this intellectual encounter of operators, users and patients can only be understood through the concepts that underlie it: the unconscious, the transfer, the impulse. Lastly our “encounter” is, as we'll understand it here, a transferential encounter. It is a network of interpersonal relations that must adapt to each other actor’s singularity and individuality.
Advisors/Committee Members: Laufer, Laurie (thesis director).
Subjects/Keywords: Psichiatria democratica; Anti-institution; Basaglia, Franco (1924-1980); Tosquelles, François (1912-1994); Institutional psychotherapy; Relations patient-doctor; Therapeutic club; Multireference transfert; Subjectivity; Medicalization; Anti-institution
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Canfora, R. (2018). Patient sujet dans l'institution : observation et comparaison franco-italiennes. Pratiques de le rencontre anti-institutionnelle Entre Basaglia et Tosquelles : The patient as subject in the institution : examination and comparison of France and Italy. (Doctoral Dissertation). Sorbonne Paris Cité. Retrieved from http://www.theses.fr/2018USPCC059
Chicago Manual of Style (16th Edition):
Canfora, Rosanna. “Patient sujet dans l'institution : observation et comparaison franco-italiennes. Pratiques de le rencontre anti-institutionnelle Entre Basaglia et Tosquelles : The patient as subject in the institution : examination and comparison of France and Italy.” 2018. Doctoral Dissertation, Sorbonne Paris Cité. Accessed April 18, 2021.
http://www.theses.fr/2018USPCC059.
MLA Handbook (7th Edition):
Canfora, Rosanna. “Patient sujet dans l'institution : observation et comparaison franco-italiennes. Pratiques de le rencontre anti-institutionnelle Entre Basaglia et Tosquelles : The patient as subject in the institution : examination and comparison of France and Italy.” 2018. Web. 18 Apr 2021.
Vancouver:
Canfora R. Patient sujet dans l'institution : observation et comparaison franco-italiennes. Pratiques de le rencontre anti-institutionnelle Entre Basaglia et Tosquelles : The patient as subject in the institution : examination and comparison of France and Italy. [Internet] [Doctoral dissertation]. Sorbonne Paris Cité; 2018. [cited 2021 Apr 18].
Available from: http://www.theses.fr/2018USPCC059.
Council of Science Editors:
Canfora R. Patient sujet dans l'institution : observation et comparaison franco-italiennes. Pratiques de le rencontre anti-institutionnelle Entre Basaglia et Tosquelles : The patient as subject in the institution : examination and comparison of France and Italy. [Doctoral Dissertation]. Sorbonne Paris Cité; 2018. Available from: http://www.theses.fr/2018USPCC059

University of Georgia
18.
Turney, Justin Matthew.
Applications of coupled cluster theory on AI, Li, N, and O-containing small molecules.
Degree: 2014, University of Georgia
URL: http://hdl.handle.net/10724/23266
► Two sets of isomers, dialuminum monoxide (AlOAl / AlAlO) and lithium nitroxide (LiON / LiNO), are investigated with a variety of high-level ab initio techniques.…
(more)
▼ Two sets of isomers, dialuminum monoxide (AlOAl / AlAlO) and lithium nitroxide (LiON / LiNO), are investigated with a variety of high-level ab initio techniques. The electronic structure of the AlAlO isomer was of particular difficulty due
to its weak metal-metal bonding, likewise for its transition state to AlOAl. A detailed study of its ground state potential energy surface was conducted to address the question of why experimentalists have been unable to detect AlAlO. A different problem
has plagued the history of lithium nitroxide. Application of one level of theory suggests LiON to be the energetic minimum. Use of another favors LiNO. Then to complicate the matter even more, there is a possibility of a bent structure as well. A
definitive study of this system including their connecting transition states has been performed using coupled cluster theory and sufficiently large basis sets.
Subjects/Keywords: ab initio quantum chemistry; coupled cluster; multireference configuration interaction; multiconfiguration self consistent field; complete active space self consistent field; dialuminum monoxide; AlOAl; AlAlO; lithium nitroxide; LiON; LiNO; potential ene
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Turney, J. M. (2014). Applications of coupled cluster theory on AI, Li, N, and O-containing small molecules. (Thesis). University of Georgia. Retrieved from http://hdl.handle.net/10724/23266
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Turney, Justin Matthew. “Applications of coupled cluster theory on AI, Li, N, and O-containing small molecules.” 2014. Thesis, University of Georgia. Accessed April 18, 2021.
http://hdl.handle.net/10724/23266.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Turney, Justin Matthew. “Applications of coupled cluster theory on AI, Li, N, and O-containing small molecules.” 2014. Web. 18 Apr 2021.
Vancouver:
Turney JM. Applications of coupled cluster theory on AI, Li, N, and O-containing small molecules. [Internet] [Thesis]. University of Georgia; 2014. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/10724/23266.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Turney JM. Applications of coupled cluster theory on AI, Li, N, and O-containing small molecules. [Thesis]. University of Georgia; 2014. Available from: http://hdl.handle.net/10724/23266
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
19.
João Paulo Gobbo.
Estudo teórico de monocarbetos de metais de transição: MnC e CoC.
Degree: 2006, University of São Paulo
URL: http://www.teses.usp.br/teses/disponiveis/46/46132/tde-20092006-131517/
► Neste trabalho, métodos ab initio multiconfiguracionais de alto nível foram empregados para estudar as estruturas eletrônicas e as ligações químicas de vários estados eletrônicos de…
(more)
▼ Neste trabalho, métodos ab initio multiconfiguracionais de alto nível foram empregados para estudar as estruturas eletrônicas e as ligações químicas de vários estados eletrônicos de dois monocarbetos de metais de transição do período 3d: MnC e CoC. Os estados eletrônicos quartetos, sextetos e octupletos energeticamente mais baixos do MnC, que estão correlacionados com os três mais baixos canais de dissociação, foram investigados teoricamente, pela primeira vez, com a abordagem Interação de Configurações Multiconfiguracional (MRCI), baseada em funções de onda do tipo Complete-Active-Space Self-Consistent-Field (CASSCF) e extensos conjuntos de bases atômicas. Energias de excitação, distâncias internucleares de equilíbrio, energias de dissociação e constantes espectroscópicas para todos os 36 estados serão apresentados. Fatores de Franck-Condon, coeficientes de Einstein e tempo de vida radioativa para a transição eletrônica X-A também serão mostrados.
Sobre o monocarbeto de cobalto (CoC), os métodos CASSCF e Teoria da Perturbação de Segunda Ordem Multiconfiguracional (CASPT2) foram empregados para estudar seus estados eletrônicos dubletos mais baixos. Três novos estados foram identificados. O estado atribuído para a banda entre 13.000 14.500 cm-1 foi cofirmado, mas ao contrário do que foi sugerido, outra configuração eletrônica foi encontrada como a mais relevante para a descrição desse estado.
In this work, high level ab initio multiconfigurational methods were employed to study the electronic structures and chemical bondings of several electronic states of two 3d transition metal monocarbides: MnC and CoC. The lowest-lying quartet, sextet, and octuplet electronic states of MnC, correlating with the three lowest-lying atomic dissociation channels, were investigated theoretically for the first time, with state-of-the-art Multireference Configuration Interaction (MRCI) approach, based on Complete-Active-Space
Self-Consistent-Field (CASSCF) wave functions and extensive basis sets. Excitation energies, equilibrium internuclear distances, dissociation energies, and spectroscopic constants for all 36 electronic states will be reported. Franck-Condon factos, Einstein coefficients, and radiative lifetimes for the X-A electronic transition will also be presented. As to the colbalt monocarbide (CoC), the CASSCF and Second Order Perturbation Theory (CASPT2) methods were employed to study its low-lying electronic dublet states. Three new states were identified. The results support the previous assignment fo the 13000 14500 cm-1, but unlike previous suggestions, another electronic configuration were found as the most important for the description of this state.
Advisors/Committee Members: Antonio Carlos Borin, Kaline Rabelo Coutinho, Mauro Carlos Costa Ribeiro.
Subjects/Keywords: metais de transição; métodos ab initio multiconfiguracionais; multireference ab initio methods; transition metals
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Gobbo, J. P. (2006). Estudo teórico de monocarbetos de metais de transição: MnC e CoC. (Masters Thesis). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/46/46132/tde-20092006-131517/
Chicago Manual of Style (16th Edition):
Gobbo, João Paulo. “Estudo teórico de monocarbetos de metais de transição: MnC e CoC.” 2006. Masters Thesis, University of São Paulo. Accessed April 18, 2021.
http://www.teses.usp.br/teses/disponiveis/46/46132/tde-20092006-131517/.
MLA Handbook (7th Edition):
Gobbo, João Paulo. “Estudo teórico de monocarbetos de metais de transição: MnC e CoC.” 2006. Web. 18 Apr 2021.
Vancouver:
Gobbo JP. Estudo teórico de monocarbetos de metais de transição: MnC e CoC. [Internet] [Masters thesis]. University of São Paulo; 2006. [cited 2021 Apr 18].
Available from: http://www.teses.usp.br/teses/disponiveis/46/46132/tde-20092006-131517/.
Council of Science Editors:
Gobbo JP. Estudo teórico de monocarbetos de metais de transição: MnC e CoC. [Masters Thesis]. University of São Paulo; 2006. Available from: http://www.teses.usp.br/teses/disponiveis/46/46132/tde-20092006-131517/

University of Georgia
20.
Wu, Chia-Hua.
Exploring chemical reaction mechanisms via high accuracy ab initio quantum chemistry.
Degree: 2014, University of Georgia
URL: http://hdl.handle.net/10724/30810
► The mechanisms and properties of SN2 halide identity exchange, radical-radical abstraction reactions and hydroxycarbene tunneling reactions are investigated via high accuracy quantum mechanical computations. The…
(more)
▼ The mechanisms and properties of SN2 halide identity exchange, radical-radical abstraction reactions and hydroxycarbene tunneling reactions are investigated via high accuracy quantum mechanical computations. The origin of the SN2 intrinsic
reaction rate enhancement has been addressed in this study. A detailed analysis is performed of R–CH2X + X– (RCH2 = propyl, ethyl, methyl, allyl, benzyl, acetonitrile; X = F, Cl) SN2 identity exchange reactions. In the traditional view, fast SN2 rates
for substrates with a multiple bond at Cβ (carbon
adjacent to the reacting Cα center) are primarily due to π-conjugative stabilization in the SN2 transition state. However, our results give a definite answer that electrostatic interactions among Cα, Cβ
and the attacking halide anion are the main driving force of the SN2 rate acceleration. The quantum tunneling computations demonstrate that several members of the hydroxycarbene family (R–COH, R = H, methyl, phenyl) are able to penetrate through ~30 kcal
mol–1 activation barriers to isomerize to aldehyde derivatives (R–CHO) with half-lives of 1–2 hrs. The intrinsic reaction path is mapped out and the Wentzel–Kramers–Brillouin approximation is used to compute tunneling probabilities. In addition,
semi-classical transition state theory shows that multidimensional vibrational coupling increases the half-life by a factor of 3-5 relative to the one-dimensional reaction coordinate analysis. Finally, rigorous one-dimensional reaction profiles are
constructed for several radical-radical abstraction reactions using Mukherjee state-specific multireference coupled cluster theory (Mk-MRCC). We demonstrate that the performance of Mk-MRCCSD(T) is superior to other popular multireference methods and its
root-mean-square deviation from full CI is only 0.24 kcal mol–1 for binding energies. The energy profile for each level of theory is extrapolated to the complete basis set limit to facilitate future kinetic studies.
Subjects/Keywords: computational chemistry; basis set extrapolation; focal point analysis; physical organic chemistry; SN2 reaction; electrostatic interactions; π-conjugative effect; combustion chemistry; radical-radical interactions; multireference coupled cluster theory (Mk-MRCC); quantum tunneling effect; hydroxycarbenes
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Wu, C. (2014). Exploring chemical reaction mechanisms via high accuracy ab initio quantum chemistry. (Thesis). University of Georgia. Retrieved from http://hdl.handle.net/10724/30810
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Wu, Chia-Hua. “Exploring chemical reaction mechanisms via high accuracy ab initio quantum chemistry.” 2014. Thesis, University of Georgia. Accessed April 18, 2021.
http://hdl.handle.net/10724/30810.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Wu, Chia-Hua. “Exploring chemical reaction mechanisms via high accuracy ab initio quantum chemistry.” 2014. Web. 18 Apr 2021.
Vancouver:
Wu C. Exploring chemical reaction mechanisms via high accuracy ab initio quantum chemistry. [Internet] [Thesis]. University of Georgia; 2014. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/10724/30810.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Wu C. Exploring chemical reaction mechanisms via high accuracy ab initio quantum chemistry. [Thesis]. University of Georgia; 2014. Available from: http://hdl.handle.net/10724/30810
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Université Montpellier II
21.
Mahmoud, Salman.
Étude théorique des molécules diatomiques BN, SiN et LaH, structure électronique et spectroscopie : Theoretical study of diatomic molecules BN, SiN and LaH, electronic structure and spectroscopy.
Degree: Docteur es, Chimie et physicochimie des matériaux, 2014, Université Montpellier II
URL: http://www.theses.fr/2014MON20080
► Une étude théorique ab initio des structures électroniques des molécules Diatomiques polaires BN, SiN et LaH dans la représentation 2s+1Λ(+/-)Ont été effectués par la méthode…
(more)
▼ Une étude théorique ab initio des structures électroniques des molécules Diatomiques polaires BN, SiN et LaH dans la représentation 2s+1Λ(+/-)Ont été effectués par la méthode du champ auto-cohérent de l'espace Actif complet (CASSCF), suivie par l'interaction de la configuration multiréférence (MRSDCI). La correction de Davidson, notée (MRSDCI+ Q), a ensuite été appliquée pour rendre compte de clusters ou agrégats quadruples non liés. L'ensemble de l'espace de configuration de CASSCF a été utilisé comme référence dans le calcul MRCI, qui a été effectués en utilisant le programme de calcul de chimie physique MOLPRO et en tirant parti de l'interface graphique Gabedit. Quarante-deux de plus bas états électroniques dans la représentation 2s+1Λ(+/-)au-dessous de 95000 cm-1 ont été étudiés de la molécule BN. Alors que vingt-huit états électroniques dans les représentations 2s+1Λ(+/-) jusqu'à 70000 cm-1 de la molécule de SiN ont été étudiés. D'autre part, les vingt-quatre bas états électroniques de LaH dans les représentations 2s+1Λ(+/-) au-dessous de 70000 cm-1 ont été étudiées par deux méthodes différentes et en prenant en considération l'effet des spin-orbite de la molécule LaH et nous avons observé la division énergétique des huit états électroniques. Les courbes d'énergie potentielle ont été construites avec la fréquence co-harmonique ωe, la distance internucléaire de l'équilibre re, les constantes de rotation Be. L'énergie électronique par rapport à l'état fondamentale Te a été calculé pour les états électroniques considérés comme des BN, SiN et la molécule LaH respectivement. En utilisant l'approche des fonctions canoniques, les valeurs propres Ev, les constantes rotationnelles Bv, la constante de distorsion centrifuge Dv et les abscisses des points de retournement Rmin and Rmax ont été calculés pour les états électroniques au niveau de vibration v=51 pour LaH molécule. Dix-huit et neuf états électroniques ont été étudiées pour la molécule BN et SiN respectivement. Pour LaH, vingt-trois états électroniques de la molécule LaH et l'effet de spin-orbite de molécule LaH sont donnés ici pour la première fois. La comparaison avec les données expérimentales et théoriques pour la plupart des constantes calculées démontre une très bonne précision. Enfin, ces résultats devraient ainsi mener à des études expérimentales plus poussées pour ces molécules. Nos résultats ont été publiés dans le Canadian Journal of Chemistry, Journal of Quantitative Spectroscopy and Radiative Transfer, nous avons deux autres articles en préparation à soumettre.
In the present work a theoretical investigation of the lowest molecular states of BN, SiN and LaH molecule, in the representation 2s+1Λ(+/-), has been performed via complete active space self-consistent field method (CASSCF) followed by multireference single and double configuration interaction method (MRSDCI). The Davidson correction noted as (MRSDCI+Q) was then invoked in order to account for unlinked quadruple clusters. The entire CASSCF configuration space was used as a reference in the…
Advisors/Committee Members: Miele, Philippe (thesis director), El Korek, Mahmoud (thesis director).
Subjects/Keywords: Molécules diatomiques; Calculs Ab initio; Configuration Interaction Multiréférence; Constants Spectroscopique; Moment électrique dipolaire de l’electron; Spin Orbite-Effets; Diatomic molecules; Ab initio Calculations; Multireference Configuration Interaction; Spectroscopic Constants; Electric Dipole Moment of the electron; Spin-Orbit effects
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Mahmoud, S. (2014). Étude théorique des molécules diatomiques BN, SiN et LaH, structure électronique et spectroscopie : Theoretical study of diatomic molecules BN, SiN and LaH, electronic structure and spectroscopy. (Doctoral Dissertation). Université Montpellier II. Retrieved from http://www.theses.fr/2014MON20080
Chicago Manual of Style (16th Edition):
Mahmoud, Salman. “Étude théorique des molécules diatomiques BN, SiN et LaH, structure électronique et spectroscopie : Theoretical study of diatomic molecules BN, SiN and LaH, electronic structure and spectroscopy.” 2014. Doctoral Dissertation, Université Montpellier II. Accessed April 18, 2021.
http://www.theses.fr/2014MON20080.
MLA Handbook (7th Edition):
Mahmoud, Salman. “Étude théorique des molécules diatomiques BN, SiN et LaH, structure électronique et spectroscopie : Theoretical study of diatomic molecules BN, SiN and LaH, electronic structure and spectroscopy.” 2014. Web. 18 Apr 2021.
Vancouver:
Mahmoud S. Étude théorique des molécules diatomiques BN, SiN et LaH, structure électronique et spectroscopie : Theoretical study of diatomic molecules BN, SiN and LaH, electronic structure and spectroscopy. [Internet] [Doctoral dissertation]. Université Montpellier II; 2014. [cited 2021 Apr 18].
Available from: http://www.theses.fr/2014MON20080.
Council of Science Editors:
Mahmoud S. Étude théorique des molécules diatomiques BN, SiN et LaH, structure électronique et spectroscopie : Theoretical study of diatomic molecules BN, SiN and LaH, electronic structure and spectroscopy. [Doctoral Dissertation]. Université Montpellier II; 2014. Available from: http://www.theses.fr/2014MON20080

University of North Texas
22.
Dinescu, Adriana.
Metals in Chemistry and Biology: Computational Chemistry Studies.
Degree: 2007, University of North Texas
URL: https://digital.library.unt.edu/ark:/67531/metadc3678/
► Numerous enzymatic reactions are controlled by the chemistry of metallic ions. This dissertation investigates the electronic properties of three transition metal (copper, chromium, and nickel)…
(more)
▼ Numerous enzymatic reactions are controlled by the chemistry of metallic ions. This dissertation investigates the electronic properties of three transition metal (copper, chromium, and nickel) complexes and describes modeling studies performed on glutathione synthetase. (1) Copper nitrene complexes were computationally characterized, as these complexes have yet to be experimentally isolated. (2)
Multireference calculations were carried out on a symmetric C2v chromium dimer derived from the crystal structure of the [(tBu3SiO)Cr(µ-OSitBu3)]2 complex. (3) The T-shaped geometry of a three-coordinate β-diketiminate nickel(I) complex with a CO ligand was compared and contrasted with isoelectronic and isosteric copper(II) complexes. (4) Glutathione synthetase (GS), an enzyme that belongs to the ATP-grasp superfamily, catalyzes the (Mg, ATP)-dependent biosynthesis of glutathione (GSH) from γ-glutamylcysteine and glycine. The free and reactant forms of human GS (wild-type and glycine mutants) were modeled computationally by employing molecular dynamics simulations, as these currently have not been structurally characterized.
Advisors/Committee Members: Cundari, Thomas R., Omary, Mohammad, Schwartz, Martin, Wilson, Angela K..
Subjects/Keywords: Quantum chemistry; density functional theory; multireference methods; molecular mechanics; molecular dynamics; Transition metals.; Glutathione.; Enzymes.; Metal ions.
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23.
Antonio Carlos Borin.
Aplicações do método interação de configuraçäes ao estudo de espectroscopia eletrônica, fotoeletrônica e ressonância quadrupolar nuclear.
Degree: 1993, University of São Paulo
URL: http://www.teses.usp.br/teses/disponiveis/46/46132/tde-04072012-090245/
► Esta tese tem como objetivo central a descrição teórica rigorosa da estrutura, de propriedades e da espectroscopia de alguns sistemas diatômicos. Como abordagem de cálculo…
(more)
▼ Esta tese tem como objetivo central a descrição teórica rigorosa da estrutura, de propriedades e da espectroscopia de alguns sistemas diatômicos. Como abordagem de cálculo ela se serve da metodologia interação de configurações na sua forma conhecida como excitações simples e duplas a partir de um conjunto de múltiplas referências (MRSD-CI), além de conjuntos base relativamente extensos de funções Gaussianas Cartesianas contraídas. Ela propõe a existência de duas novas espécies moleculares, BeC e BeC+, para as quais um total de 20 estados eletrônicos (13 para o BeC e 7 para o BeC+) foram caracterizados através de suas curvas de potencial e de seus respectivos estados vibro-rotacionais. Constantes espectroscópicas para cada estado foram calculadas e os momentos elétricos das transições eletrônicas mais relevantes foram também estudados. Essas transições foram analisadas tanto em termos de probabilidades de transição calculadas via momento de
transição como por meio de fatores de Franck-Condon. Transições vibro-rotacionais dentro de um mesmo estado eletrônico foram ainda examinadas. Para esses vários estados, tempos de vida radiativa foram também calculados. Complementando essa descrição espectroscópica, uma discussão sobre a natureza da ligação química nesses sistemas foi ainda apresentada. Conjugando os resultados obtidos para essas duas espécies, o espectro fotoeletrônico da molécula BeC foi simulado servindo-se da aproximação de Franck-Condon para estimar as intensidades das linhas de cada banda. Além de propriedades eletrônicas como o momento de dipolo, cálculos de gradiente de campo elétrico no átomo de berílio em função da distância internuclear foram também realizados com o propósito de fornecer dados teóricos confiáveis que permitam a determinação experimental do momento quadrupolar do núcleo de 9Be sobre o qual existe certa controvérsia na literatura. Tais cálculos, realizados para os sitemas BeH+ e BeC, além de
incluirem o efeito da vibração molecular no gradiente de campo elétrico na forma de uma média vibracional, mostraram que a aproximação de Buckingham usada por alguns grupos não é apropriada para descrever tal efeito.
The aim of this thesis is to describe theoretically the structure, properties, and the spectroscopy of some diatomic species using the multirefence single and double excitations configuration interaction approach, and an extensive atomic basis set of contracted Cartesian Gaussian orbitals. Two new diatomic species are proposed, BeC and BeC+, for which twenty electronic states have been characterized (13 for BeC, and 7 for BeC+) by means of their potential energy curves and vibro-rotational states. Spectroscopic constants for both of them have been computed, as well as electric moments of the most relevant electronic transitions. The transitions have been described by using either transitions probabilities computed with the aid of the theoretical transition moment
functions, or by Franck-Condon factors. Vibro-rotational transitions within the same electronic state have also been…
Advisors/Committee Members: Fernando Rei Ornellas.
Subjects/Keywords: Espectroscopia eletrônica; Espectroscopia fotoeletrônica; Físico-química; Método interação de configurações; Métodos ab initio; Ab initio method; Electronic spectroscopy; Multireference configuration interaction; Photoelectronic spectroscopy; Physical chemistry
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APA ·
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APA (6th Edition):
Borin, A. C. (1993). Aplicações do método interação de configuraçäes ao estudo de espectroscopia eletrônica, fotoeletrônica e ressonância quadrupolar nuclear. (Doctoral Dissertation). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/46/46132/tde-04072012-090245/
Chicago Manual of Style (16th Edition):
Borin, Antonio Carlos. “Aplicações do método interação de configuraçäes ao estudo de espectroscopia eletrônica, fotoeletrônica e ressonância quadrupolar nuclear.” 1993. Doctoral Dissertation, University of São Paulo. Accessed April 18, 2021.
http://www.teses.usp.br/teses/disponiveis/46/46132/tde-04072012-090245/.
MLA Handbook (7th Edition):
Borin, Antonio Carlos. “Aplicações do método interação de configuraçäes ao estudo de espectroscopia eletrônica, fotoeletrônica e ressonância quadrupolar nuclear.” 1993. Web. 18 Apr 2021.
Vancouver:
Borin AC. Aplicações do método interação de configuraçäes ao estudo de espectroscopia eletrônica, fotoeletrônica e ressonância quadrupolar nuclear. [Internet] [Doctoral dissertation]. University of São Paulo; 1993. [cited 2021 Apr 18].
Available from: http://www.teses.usp.br/teses/disponiveis/46/46132/tde-04072012-090245/.
Council of Science Editors:
Borin AC. Aplicações do método interação de configuraçäes ao estudo de espectroscopia eletrônica, fotoeletrônica e ressonância quadrupolar nuclear. [Doctoral Dissertation]. University of São Paulo; 1993. Available from: http://www.teses.usp.br/teses/disponiveis/46/46132/tde-04072012-090245/
24.
Κούκουνας, Κωνσταντίνος.
Ab initio διερεύνησις της ηλεκτρονιακής δομής των διατομικών μεταλλο-φθοριδίων MF, M=Fe, Co, Ni, και Cu.
Degree: 2007, National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ)
URL: http://hdl.handle.net/10442/hedi/18569
► The present dissertation deals with the theoretical investigation of the electronic structure of the first row transition metal diatomic fluorides MF, M = Fe, Co,…
(more)
▼ The present dissertation deals with the theoretical investigation of the electronic structure of the first row transition metal diatomic fluorides MF, M = Fe, Co, Ni, and Cu. We studied the ground and low-lying excited states of the FeF, CoF, NiF, and CuF molecular systems using the highly correlated ab initio methodologies MRCI and RCCSD(T) in conjunction with recently developed large to very large basis sets. Equilibrium geometries and the usual spectroscopic constants, ωe, ωexe, ZPE and ae, were calculated for a total of 34 studied states, while full potential energy curves (PEC) at the MRCI level were constructed for the most of these states. The ground states’ X6Δ (FeF), X 2Π (NiF), and X 1Σ+ (CuF) dissociation energies are calculated equal to 109, 103, and 99 kcal/mol, correspondingly, in harmony with existing experimental data. As for CoF, our calculations indicate a 5Φ ground state, and not a 3Φ, as experimentalists, with certain reservations, suggest. The 5Φ’s dissociation energy is estimated to be 98 kcal/mol. The “bonding” in the MF species is highly ionic, as implied by the common chemical empiricism on fluorine-containing systems, and can be attributed to the coulombic interaction of the low-lying atomic M+ terms with the practically spherical, negatively charged, F-(1S) anion. The symmetry of the involved M+ terms determine of course the symmetry of the arising molecular states. The in situ ionic character of the MF states is reflected in the similar morphology of the calculated potential curves, and is further corroborated by the really successful fitting of calculated PECs to a Rittner-type potential. Relativistic effects, through the Douglas-Kroll-Hess approximation, and core-valence effects were also taken into account, and proved that specially tuned basis sets, containing ad hoc optimized core functions are necessary in order to avoid wrong and/or misleading numerical results.
Η θεωρητική διερεύνησις της ηλεκτρονιακής δομής των διατομικών φθοριδίων MF των μετάλλων μεταπτώσεως της πρώτης σειράς, Μ = Fe, Co, Ni, και Cu, απετέλεσε το αντικείμενο της παρούσης διατριβής. Χρησιμοποιώντας τις υψηλού επιπέδου ab initio μεθοδολογίες MRCI και RCCSD(T), εν συνδυασμώ με προσφάτως ανεπτυχθέντα πολύ μεγάλα βασικά σύνολα, μελετήσαμε τις θεμελιώδεις και χαμηλώς κείμενες διηγερμένες καταστάσεις των FeF, CoF, NiF, και CuF. Υπολογίσαμε την γεωμετρία και τις συνήθεις φασματοσκοπικές σταθερές ωe, ωexe, ZPE και ae, των συνολικά 34 διερευνηθέντων καταστάσεων, και κατασκευάσαμε τις πλήρεις δυναμικές καμπύλες στο επίπεδο MRCI των περισσοτέρων εξ’ αυτών. Η ενέργεια διαστάσεως των θεμελιωδών καταστάσεων X6Δ (FeF), X 2Π (NiF), και X 1Σ+(CuF) υπελογίσθη ίση με 109, 103, και 99 kcal/mol, αντιστοίχως, σε συμφωνία με τα υπάρχοντα πειραματικά δεδομένα. Ως X-κατάστασις του CoF, προκρίνεται από τους υπολογισμούς μας (που αποτελούν την πρώτη θεωρητική μελέτη επί του CoF) μία κατάστασις συμμετρίας 5Φ, και όχι 3Φ όπως ισχυρίζονται οι πειραματικοί, με ενέργεια διαστάσεως ίση με 98 kcal/mol. Σε συμφωνία με την «κοινή» χημική εμπειρία…
Subjects/Keywords: Υπολογισμοί πρώτων αρχών; Διατομικά μεταλλο-φθορίδια; Καμπύλες δυναμικής ενέργειας; Σύνολο βάσεων; Ab initio; Diatomic transition metal fluorides; Potential energy curves; Quantitative basis sets; Multireference configuration interaction; Coupled cluster
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Κούκουνας, . . (2007). Ab initio διερεύνησις της ηλεκτρονιακής δομής των διατομικών μεταλλο-φθοριδίων MF, M=Fe, Co, Ni, και Cu. (Thesis). National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ). Retrieved from http://hdl.handle.net/10442/hedi/18569
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Κούκουνας, Κωνσταντίνος. “Ab initio διερεύνησις της ηλεκτρονιακής δομής των διατομικών μεταλλο-φθοριδίων MF, M=Fe, Co, Ni, και Cu.” 2007. Thesis, National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ). Accessed April 18, 2021.
http://hdl.handle.net/10442/hedi/18569.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Κούκουνας, Κωνσταντίνος. “Ab initio διερεύνησις της ηλεκτρονιακής δομής των διατομικών μεταλλο-φθοριδίων MF, M=Fe, Co, Ni, και Cu.” 2007. Web. 18 Apr 2021.
Vancouver:
Κούκουνας . Ab initio διερεύνησις της ηλεκτρονιακής δομής των διατομικών μεταλλο-φθοριδίων MF, M=Fe, Co, Ni, και Cu. [Internet] [Thesis]. National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ); 2007. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/10442/hedi/18569.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Κούκουνας . Ab initio διερεύνησις της ηλεκτρονιακής δομής των διατομικών μεταλλο-φθοριδίων MF, M=Fe, Co, Ni, και Cu. [Thesis]. National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ); 2007. Available from: http://hdl.handle.net/10442/hedi/18569
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
25.
Κερκινές-Κεραμηδάς, Ιωάννης-Σώζων.
{Ι.} Θεωρητική μελέτη των μεταλλοκαρβιδίων TiC+, VC+ και CrC+. ΙΙ. Η φύση του χημικού δεσμού του κατιόντος N5+ και συγγενών συστημάτων.
Degree: 2003, National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ)
URL: http://hdl.handle.net/10442/hedi/22370
► The present Thesis deals with the high-level theoretical study of several small molecular systems with the help of Quantum Mechanics. Two categories of molecules were…
(more)
▼ The present Thesis deals with the high-level theoretical study of several small molecular systems with the help of Quantum Mechanics. Two categories of molecules were studied: a) In the first part of the work, geometrical and energetic parameters were calculated, as well as the bonding characteristics of the ground and several low-lying excited states of the cationic carbides MC+ of the transition metal atoms M = Ti, V, and Cr, while older results regarding ScC+ were also recalled for comparison purposes. Only the binding energies of their ground states - of unknown symmetry - were experimentally available for these systems. The total number of states studied at the CASSCF + 1 + 2 (=MRCI) and MRCI+Q levels of theory were 62 (ScC+: 13, TiC+: 13, VC+: 17, CrC+: 19). Two different kinds of bonds were found to play an important role in determining the ground state symmetry of the MC+ carbides. In the first case, the metal cation combines with C(3P; Μ = 0) to give two p bonds (1½ in the ScC+ case) and half a s bond (i.e. a one-electron bond). This bonding situation determines unambiguously the ground states of the first two metal carbide cations, ScC+(X3P) and TiC+(Χ2S+). In the second case, the M+ and C fragments are triply bonded (one s and two p bonds). The resulting triply bonded states compete strongly with the former ones in VC+ and CrC+. In our highest level of theory, VC+ falls under the first category (X 3D), while CrC+ under the second one (X 2D). In ScC+ and TiC+, these triply bonded states lie substantially higher (14.0 and 39.2 kcal/mol respectively at the MRCI level). b) In the second part of the present work, the structure of the recently isolated cation Ν5+ was studied, a molecular system which caused a lot of discussion and work, as shown from the recent chemical literature. Using simple chemical arguments and high-level theoretical calculations, the origin of its highly symmetrical structure and its features were determined. Understanding the bonding characteristics of N5+ led to a new family of chemical compounds, not found in the literature, which are predicted to be experimentally isolable, e.g., the N(NH3)2+ cation; some of these compounds contain noble gas atoms, like HCAr2+ and HCKr2+, in which noble gases are bonded to carbon with plain “dative semi-polar” bonds.
Η παρούσα διατριβή αφορά τη θεωρητική μελέτη υψηλού επιπέδου διαφόρων μικρών μοριακών συστημάτων με τη χρήση της Κβαντικής Μηχανικής. Οι κατηγορίες των μορίων τα οποία μελετήθηκαν είναι δύο: α) Στο πρώτο μέρος, υπολογίσθηκαν γεωμετρικές και ενεργειακές παράμετροι καθώς και τα δεσμικά χαρακτηριστικά των θεμελιωδών και αρκετών χαμηλώς κειμένων διηγερμένων καταστάσεων των κατιοντικών καρβιδίων MC+ των στοιχείων μεταπτώσεως M = Ti, V, και Cr, ενώ ανεφέρθησαν και για λόγους συγκρίσεως αντίστοιχα δεδομένα από παλαιότερους υπολογισμούς στο ScC+. Το μόνο γνωστό στη βιβλιογραφία για τα συστήματα αυτά ήταν οι ενέργειες διασπάσεως των αγνώστου συμμετρίας θεμελιωδών καταστάσεών τους. Ο συνολικός αριθμός καταστάσεων ο οποίος μελετήθηκε στα επίπεδα…
Subjects/Keywords: Θεωρητικοί υπολογισμοί; Κβαντική χημεία; Μεταλλοκαρβίδια; Πολυζωτούχες ενώσεις; Χημεία ευγενών αερίων; Καμπύλες δυναμικής ενέργειας; Ιστορία κβαντικής χημείας; Μέταλλα μετάπτωσης; AB initio calculations; Multireference configuration interaction; Potential energy curves; HEDM; Quantum chemistry; Polynitrocen compounds; Transition metal carbides; Noble gas chemistry
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Κερκινές-Κεραμηδάς, . . (2003). {Ι.} Θεωρητική μελέτη των μεταλλοκαρβιδίων TiC+, VC+ και CrC+. ΙΙ. Η φύση του χημικού δεσμού του κατιόντος N5+ και συγγενών συστημάτων. (Thesis). National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ). Retrieved from http://hdl.handle.net/10442/hedi/22370
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Κερκινές-Κεραμηδάς, Ιωάννης-Σώζων. “{Ι.} Θεωρητική μελέτη των μεταλλοκαρβιδίων TiC+, VC+ και CrC+. ΙΙ. Η φύση του χημικού δεσμού του κατιόντος N5+ και συγγενών συστημάτων.” 2003. Thesis, National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ). Accessed April 18, 2021.
http://hdl.handle.net/10442/hedi/22370.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Κερκινές-Κεραμηδάς, Ιωάννης-Σώζων. “{Ι.} Θεωρητική μελέτη των μεταλλοκαρβιδίων TiC+, VC+ και CrC+. ΙΙ. Η φύση του χημικού δεσμού του κατιόντος N5+ και συγγενών συστημάτων.” 2003. Web. 18 Apr 2021.
Vancouver:
Κερκινές-Κεραμηδάς . {Ι.} Θεωρητική μελέτη των μεταλλοκαρβιδίων TiC+, VC+ και CrC+. ΙΙ. Η φύση του χημικού δεσμού του κατιόντος N5+ και συγγενών συστημάτων. [Internet] [Thesis]. National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ); 2003. [cited 2021 Apr 18].
Available from: http://hdl.handle.net/10442/hedi/22370.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Κερκινές-Κεραμηδάς . {Ι.} Θεωρητική μελέτη των μεταλλοκαρβιδίων TiC+, VC+ και CrC+. ΙΙ. Η φύση του χημικού δεσμού του κατιόντος N5+ και συγγενών συστημάτων. [Thesis]. National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ); 2003. Available from: http://hdl.handle.net/10442/hedi/22370
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
.