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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Some chemical applications of the Gaussian-2 and Gaussian-3 methods.

January 2000 (has links)
Chien Siu-Hung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references. / Abstracts in English and Chinese. / Abstract (English) / Abstract (Chinese) / Acknowledgements / Table of Contents / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- The Gaussian-2 Method / Chapter 1.2 --- The Gaussian-3 Method / Chapter 1.3 --- The G3 Method with Reduced Moller-Plesset Order and Basis Set / Chapter 1.4 --- Calculated Thermochemical Data / Chapter 1.5 --- Remark on the Location of Transition State / Chapter 1.6 --- Scope of the Thesis / Chapter 1.7 --- References / Chapter Chapter 2 --- "Energetics and Structures of the Carbonyl Chloride Radical, Oxalyl Chloride, and Their Cations" --- p.6 / Chapter 2.1 --- Introduction / Chapter 2.2 --- Computational Methods / Chapter 2.3 --- Results and Discussion / Chapter 2.3.1 --- Carbonyl Chloride and Its Cation / Chapter 2.3.2 --- The anti and syn Conformers of Oxalyl Chloride and Oxalyl Chloride Cation / Chapter 3.3.3 --- The anti and gauche Conformers of (ClCO) 2 and the TS Linking Them / Chapter 2.4 --- Conclusions / Chapter 2.5 --- Publication Note / Chapter 2.6 --- References / Chapter Chapter 3 --- "An Isomeric Study of N5, N5+,and N5- : A Gaussian-3 Investigation" --- p.17 / Chapter 3.1 --- Introduction / Chapter 3.2 --- Computational Methods / Chapter 3.3 --- Results and Discussion / Chapter 3.3.1 --- "The N5 Isomers """ / Chapter 3.3.2 --- The N5+ Isomers / Chapter 3.3.3 --- The N5- Isomers / Chapter 3.3.4 --- Comparison of the G3 and G3(MP2) Results / Chapter 3.4 --- Conclusions / Chapter 3.5 --- Publication Note / Chapter 3.6 --- References / Chapter Chapter 4 --- Thermochemistry of Hydrochlorofluorosilanes : An Ab Initio Gaussian-3 Study --- p.28 / Chapter 4.1 --- Introduction / Chapter 4.2 --- Computational Methods / Chapter 4.3 --- Results and Discussion / Chapter 4.3.1 --- Heats of Formation for Neutral HCFSis / Chapter 4.3.2 --- Ionization Energies / Chapter 4.3.3 --- Electron Affinities / Chapter 4.3.4 --- Proton Affinities / Chapter 4.3.5 --- Acidities / Chapter 4.3.6 --- G3 versus G3(MP2) / Chapter 4.4 --- Conclusions / Chapter 4.5 --- Publication Note / Chapter 4.6 --- References / Chapter Chapter 5 --- A Gaussian-3 Study of the Photodissociation Channels of Thiirane --- p.48 / Chapter 5.1 --- Introduction / Chapter 5.2 --- Computational Methods / Chapter 5.3 --- Results and Discussion / Chapter 5.3.1 --- The Heats of Reactions / Chapter 5.3.2 --- The Dissociation Channels Taking Place at the Ground State / Chapter 5.3.3 --- The Dissociation Channels Taking Place at Excited States / Chapter 5.4 --- Conclusions / Chapter 5.5 --- References / Chapter Chapter 6 --- A Gaussian-3 Study of the VUV Photoionization and Photodissociation of Chloropropylene Oxide --- p.59 / Chapter 6.1 --- Introduction / Chapter 6.2 --- Computational Methods / Chapter 6.3 --- Results and Discussion / Chapter 6.3.1 --- Ionization Energy / Chapter 6.3.2 --- Dissociation Channels / Chapter 6.4 --- Conclusions / Chapter 6.5 --- Publication Note / Chapter 6.6 --- References / Chapter Chapter 7 --- Conclusions --- p.69 / Appendix A The Gaussian-n (n=l-3) Theoretical Models --- p.71 / Chapter A.1 --- The G1 and G2 Theories / Chapter A.2 --- The G3 Theory / Chapter A.3 --- The G3(MP2) Theory / "Appendix B Calculation of Enthalpy at 298 K,H298" --- p.74
42

Ab initio study of the structures, energetics and reactions of some chemical systems.

January 2002 (has links)
Li Chi-Lun. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references. / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgements --- p.iii / Table of Contents --- p.iv / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Remark on the Location of Transition Structures --- p.1 / Chapter 1.2 --- Scope of the Thesis --- p.1 / Chapter 1.3 --- References --- p.2 / Chapter Chapter 2 --- "A Gaussian-3 Study on the Photodissociation of Phenylacetylene and Formation of 1,3,5-Hexatriyne" --- p.5 / Chapter 2.1 --- Introduction --- p.6 / Chapter 2.2 --- Computational Method --- p.7 / Chapter 2.3 --- Results and Discussion --- p.8 / Chapter 2.3.1 --- Phenylacetylene → Acetylene + Benzyne --- p.8 / Chapter 2.3.2 --- "Phenylacetylene → Acetylene + (Z)-3 -Hexene- 1,5-diyne" --- p.9 / Chapter 2.3.3 --- "(Z)-3-Hexene-l,5-diyne / (E)-3 -Hexene-1,5-diyne → 1,3,5-Hexatriyne and Molecular Hydrogen" --- p.9 / Chapter 2.3.4 --- Evaluation of Thermochemical Data --- p.10 / Chapter 2.3.5 --- Evaluation of Ion Energetics Data --- p.10 / Chapter 2.4 --- Conclusions --- p.10 / Chapter 2.5 --- References --- p.11 / Chapter Chapter 3 --- A Gaussian-3 Study of the Photoionization and Dissociative Photoionization Channels of Cyanoethylene --- p.21 / Chapter 3.1 --- Introduction --- p.22 / Chapter 3.2 --- Computational Method --- p.22 / Chapter 3.3 --- Results and Discussion --- p.23 / Chapter 3.3.1 --- Bond Cleavage Reactions --- p.23 / Chapter 3.3.2 --- Dissociation Channels Involving Transition Structures --- p.25 / Chapter 3.4 --- Conclusions --- p.25 / Chapter 3.5 --- References --- p.26 / Chapter Chapter 4 --- "A Gaussian´ؤ2 Study of Structures, Energetics, and Reactions of C2H3S- Anions" --- p.34 / Chapter 4.1 --- Introduction --- p.35 / Chapter 4.2 --- Computational Method --- p.35 / Chapter 4.3 --- Results and Discussion --- p.36 / Chapter 4.3.1 --- Thioformylmethyl Anion --- p.37 / Chapter 4.3.2 --- Thioacetyl Anion --- p.37 / Chapter 4.3.3 --- Cyclic C2H3S- Ions --- p.37 / Chapter 4.3.4 --- CH2SCH- --- p.38 / Chapter 4.3.5 --- 2-Thiovinyl Anion --- p.38 / Chapter 4.3.6 --- 1-Thiovinyl Anion --- p.39 / Chapter 4.3.7 --- Intramolecular Rearrangements of 1- --- p.39 / Chapter 4.3.8 --- Intramolecular Rearrangements of Cyclic C2H3S- ions and 1´ؤThiovinyl Anion --- p.39 / Chapter 4.4 --- Conclusions --- p.40 / Chapter 4.5 --- References --- p.40 / Chapter Chapter 5 --- "Theoretical Studies of Transition Metal Complexes: Bond Energies for Fe+-D, Fe+-H2O, and Fe+-CO" --- p.51 / Chapter 5.1 --- Introduction --- p.52 / Chapter 5.2 --- Computational Method --- p.53 / Chapter 5.3 --- Results and Discussion --- p.54 / Chapter 5.3.1 --- Fe+-D --- p.54 / Chapter 5.3.2 --- Fe+-CO --- p.54 / Chapter 5.3.3 --- Fe+-H2O --- p.55 / Chapter 5.4 --- Conclusions --- p.56 / Chapter 5.5 --- References --- p.57 / Chapter Chapter 6 --- Ab Initio Study of the Charge-Delocalized and -Localized Form of the Rhodizonate Dianion --- p.61 / Chapter 6.1 --- Introduction --- p.62 / Chapter 6.2 --- Computational Method --- p.63 / Chapter 6.3 --- Results and Discussion --- p.64 / Chapter 6.3.1 --- Charge-Localized C6062- --- p.64 / Chapter 6.3.2 --- Charge-Delocalized C6062- --- p.64 / Chapter 6.4 --- Conclusions --- p.65 / Chapter 6.5 --- References --- p.66 / Chapter Chapter 7 --- "Franck-Condon Factor Simulated Spectra of the Cations of cis-2-Butene,trans-2-Butene, Isobutene, cis-Dichloroethene, and trans-Dichloroethene" --- p.71 / Chapter 7.1 --- Introduction --- p.72 / Chapter 7.2 --- Computational Method --- p.72 / Chapter 7.3 --- Results and Discussion --- p.73 / Chapter 7.3.1 --- cis-2-Butene Cation --- p.73 / Chapter 7.3.2 --- trans-2-Butene Cation --- p.74 / Chapter 7.3.3 --- cis-Dichloroethene Cation --- p.75 / Chapter 7.3.4 --- trans-Dichloroethene Cation --- p.76 / Chapter 7.3.5 --- Isobutene --- p.76 / Chapter 7.4 --- Conclusions --- p.77 / Chapter 7.5 --- References --- p.77 / Chapter Chapter 8 --- Conclusions --- p.88 / Appendix A --- p.89 / Appendix B --- p.91 / Appendix C --- p.92
43

Tunable laser spectroscopy of the NaNe A² -X² ⁺ system

Ahmad Bitar, Riad Nimr Abdel-Ghani January 1977 (has links)
Thesis. 1977. Sc.D.--Massachusetts Institute of Technology. Dept. of Physics. / Microfiche copy available in Archives and Science. / Bibliography : leaves 221-223. / by Riad Ahmad Bitar. / Sc.D.
44

Theoretical study of the structures, energetics and reactions of some chemical systems.

January 2005 (has links)
Lam Chow Shing. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references. / Abstracts in English and Chinese. / Thesis Examination Committee --- p.i / Abstract --- p.ii / Acknowledgements --- p.iv / Table of Contents --- p.v / List of Tables --- p.vii / List of Figures --- p.viii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- The Gaussian-3 Method --- p.1 / Chapter 1.2 --- The G3 Method with Reduced MΦller- Plesset Order and Basis Set --- p.2 / Chapter 1.3 --- Density Functional Theory (DFT) --- p.3 / Chapter 1.4 --- Calculation of Thermodynamical Data --- p.3 / Chapter 1.5 --- Remark on the Location of Transition Structures --- p.3 / Chapter 1.6 --- Natural Bond Orbital (NBO) Analysis --- p.4 / Chapter 1.7 --- Scope of the Thesis --- p.4 / Chapter 1.8 --- References --- p.5 / Chapter Chapter 2 --- Theoretical Study of Tri-s-triazine and Its Derivatives --- p.7 / Chapter 2.1 --- Introduction --- p.7 / Chapter 2.2 --- Methods of Calculation --- p.9 / Chapter 2.3 --- Results and Discussion --- p.9 / Chapter 2.3.1. --- Property of Tri-s-triazine --- p.9 / Chapter 2.3.2. --- Substituent Effects on the Properties of the Tri-s-triazine Parent Molecule --- p.10 / Chapter 2.3.3. --- Heats of Formation of Derivatives of Tri-s-triazine --- p.20 / Chapter 2.4 --- Conclusion --- p.22 / Chapter 2.5 --- References --- p.22 / Chapter Chapter 3 --- A Gaussian-3 Study of the Dissociative Photoionization of Acetone --- p.25 / Chapter 3.1 --- Introduction --- p.25 / Chapter 3.2 --- Methods of Calculation --- p.26 / Chapter 3.3 --- Results and Discussion --- p.26 / Chapter 3.3.1. --- "Formation of m/z = 42 (CH2CO+.),43 (CH3CO+) Ions" --- p.31 / Chapter 3.3.2. --- Formation of m/z = 43 (c-CH2CHO+) and m/z = 15 (CH3+) Ions --- p.32 / Chapter 3.3.3. --- Formation of m/z = 57 (CH3COCH2+) Ions --- p.37 / Chapter 3.3.4. --- Formation of m/z = 39 (C3H3+) Ions --- p.38 / Chapter 3.4 --- Conclusion --- p.40 / Chapter 3.5 --- Publication Note --- p.40 / Chapter 3.6 --- References --- p.40 / Chapter Chapter 4 --- "A G3(MP2) Study of the C3H60+. Isomers Fragmented from l,4-Dioxane+" --- p.42 / Chapter 4.1 --- Introduction --- p.42 / Chapter 4.2 --- Methods of Calculation --- p.43 / Chapter 4.3 --- Results and Discussion --- p.44 / Chapter 4.3.1. --- "Formation of C3H60+. Isomers 1 and 2 via Fragmentation of 1,4-Dioxane+" --- p.44 / Chapter 4.3.2. --- Reaction with Acetonitrile --- p.55 / Chapter 4.3.3. --- Reaction with Formaldehyde --- p.57 / Chapter 4.3.4. --- Reaction with Ethylene --- p.61 / Chapter 4.3.5. --- Reaction with Propene --- p.63 / Chapter 4.4 --- Conclusion --- p.67 / Chapter 4.5 --- Publication Note --- p.68 / Chapter 4.6 --- References --- p.68 / Chapter Chapter 5 --- A Computational Study of the Photodissociation Channels of Chloroiodomethane --- p.71 / Chapter 5.1 --- Introduction --- p.71 / Chapter 5.2 --- Methods of Calculation --- p.73 / Chapter 5.3 --- Results and Discussion --- p.74 / Chapter 5.3.1 --- CH2C1 + I(2P1/2) and CH2C1 + I(2P3/2) Channels --- p.77 / Chapter 5.3.2 --- "CH2I + C1(2P3/2,1/2) Channel" --- p.78 / Chapter 5.3.3 --- CHI + HC1 Channel --- p.80 / Chapter 5.3.4 --- CH2 + IC1 Channel --- p.81 / Chapter 5.4 --- Conclusion --- p.82 / Chapter 5.5 --- Publication Note --- p.83 / Chapter 5.6 --- References --- p.83 / Chapter Chapter 6 --- Conclusion --- p.86 / Appendix A --- p.87 / Appendix B --- p.89
45

Investigating excited electronic states in fullerenes and polycyclic aromatic hydrocarbons using Femtosecond Laser Photoelectron spectrometry

Bohl, Elvira January 2016 (has links)
Fullerenes have highly excited electronic states with interesting properties for possible wide ranging applications including in electronics. These highly excited, Rydberg-like states, so-called superatom molecular orbitals (SAMOs), are diffuse low-angular momenta states with molecular orbitals centred on the hollow fullerene core. The SAMOs can be detected by femtosecond photoelectron spectroscopy (PES) and characterised by photoelectron angular distributions (PADs) combined with time-dependent density functional theory (TD-DFT) calculations. The photoelectron spectra of C60 and C70 show a peak structure below kinetic energies corresponding to the photon energy, superimposed on a thermal electron background. This peak structure was assigned to one-photon ionisation of the SAMO states based on PAD and TD-DFT. In this thesis, studies of the fullerene species C82 and Sc3N@C80 revealed PES and PAD with similar features to C60 and C70. The SAMO peaks became less prominent compared to the thermal electron background for increasing molecular size and decreasing symmetry, and were almost absent for the endohedral species. To provide more information about the influence of encapsulated atoms in the fullerene cage on the SAMO states, experiments on Li@C60 have been carried out. A lower thermal electron emission temperature and a splitting of the SAMO peaks has been observed for Li@C60 compared to C60. Nevertheless the binding energies are remarkably similar in all investigated fullerenes, which is important for any applications. Since the binding energies are about the same, but the ionisation potentials of the fullerenes are different, the excitation energy to the SAMOs scales with the ionisation energy. The reasons for the well-pronounced peak structure of the SAMO states in the PES of C60 could be explained by the similarity of the SAMOs to Rydberg states along with the higher photoionisation probabilities compared to valence states which were modelled by Benoît Mignolet and Françoise Remacle. As the SAMOs are highly excited electronic states, like Rydberg states, the potential energy surface of the neutral molecule and the ionised molecule are similar. Therefore the vibrational energy is conserved in the molecule during the photoionisation on the femtosecond time scale. The TD-DFT calculations on C60, carried out by Benoît Mignolet and Françoise Remacle, revealed the photoionisation probabilities of the SAMOs to be at least three orders of magnitude higher than for non-SAMOs for the applied experimental conditions. To test the prediction of the model, the relative photoionisation probabilities of the s-SAMO to p-SAMO and the s-SAMO to d-SAMO were obtained experimentally from the PES at various photon energies (2-3.5 eV) within this work. The analysis indicates remarkable agreement between the experiment and the theoretical values. Further quantum chemical calculations on a series of polycyclic aromatic hydrocarbons (PAHs) were carried out within this thesis, which revealed similar Rydberg-like molecular orbitals in analogy to the SAMOs in fullerenes. The first series included benzene, naphthalene, anthracene, tetracene, pentacene and hexacene. The second series consisted of phenanthrene, pyrene and coronene. Finally, the third series covered cubane, adamantane and dodecahedral C20. All modelled molecules showed diffuse, excited electronic states similar to the SAMOs. Within each series the binding energies of these states decrease with increasing molecular size as well as the ionisation energies, except for the 3rd series. A comparison between all series shows that the binding energies of the states for the 3rd series (the 3-D series) are slightly higher than for the 1st and 2nd series in relation to similar molecular size. The results of the coronene calculations are compared to experimental photoelectron spectra and are shown to be in good agreement with the experiments.
46

Spin-orbit coupling effects in diatomic molecules

Cooper, D. L. January 1981 (has links)
Spin-orbit coupling and the related effects of A-doubling and spin-splitting have been well known to spectroscopists for some considerable time. The importance of these phenomena stems from the advent of radioastronomy and the study of the interstellar medium. Identification of the molecules, and the molecular transitions, in the interstellar dust clouds is necessary for an understanding of the cooling process by which these clouds can contract to form new stars.
47

Characterization of unknown chemicals using gas chromatography/fourier transform ion cyclotron resonance mass spectrometry and ab-initio calculations /

Silwal, Indira K.C., January 2008 (has links)
Thesis (Ph.D.) in Chemistry--University of Maine, 2008. / Includes vita. Includes bibliographical references (leaves 181-195).
48

The coordination chemistry and magnetism of compounds derived from formylphenols and diaminomaleonitrile /

Park, Murray Kitchener, January 1997 (has links)
Thesis (M. Sc.), Memorial University of Newfoundland, 1998. / Bibliography: leaves 106-111.
49

Investigation of the structure and bonding of metal complexes through the use of density functional theory

Brett, Constance M., January 2005 (has links)
Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Document formatted into pages; contains xxxi, 309 p.; also includes graphics Includes bibliographical references. Available online via OhioLINK's ETD Center
50

Molecular orbital calculations for transition metal complexes containing pi-acceptor ligands

DeKock, Roger L. January 1970 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1970. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

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