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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.
11

Computational investigations of the dynamics of chlorine dioxide /

Stedl, Todd Robert. January 2003 (has links)
Thesis (Ph. D.)--University of Washington, 2003. / Vita. Includes bibliographical references (leaves 115-124).
12

The performance of the non-iterative and iterative triples corrected EOMIP-CCSD in characterizing stationary points of excited state potential energy surfaces

Saeh, Jamal Carlos 28 August 2008 (has links)
Not available / text
13

Anisotropic potential energy surfaces for atmospheric gas : unsaturated hydrocarbon molecule interactions from differential scattering experiments /

Stevenson, Kip Patrick, January 1997 (has links)
Thesis (Ph. D.)--University of Washington, 1997. / Vita. Includes bibliographical references (leaves [193]-203).
14

The performance of the non-iterative and iterative triples corrected EOMIP-CCSD in characterizing stationary points of excited state potential energy surfaces

Saeh, Jamal Carlos. January 2002 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2002. / Vita. Includes bibliographical references. Available also from UMI Company.
15

Intermolecular communication via lattice phonons, probed by ultrafast spectroscopy /

Rohrdanz, Mary A., January 2005 (has links)
Thesis (Ph. D.)--University of Oregon, 2005. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 79-80). Also available for download via the World Wide Web; free to University of Oregon users.
16

Density functional calculation of simple molecules

Olaoye, Olufemi Opeyemi. 03 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2012. / AFRIKAANSE OPSOMMING: Berekeninge met Density Functional Theory (DFT) is ’n nuttige tegniek om die dinamika van molekules op potensiële energievlakke te verstaan. Beginnende met ’n prototipe molekuul formaldimien, wat die kern vorm van die groter fotochromiese molekuul dithizonatophenyl kwik (DPM), word die modellering van die molekuul meer ingewikkeld tot laasgenoemde bestudeer kan word asook sy fotochromiese afgeleides wat vervanging van elektronryk en elektronarm radikale by orto, meta en para posisies van die phenyl ringe insluit. DFT berekeninge word met spektra van Absorpsiespektroskopie met UV en sigbare lig asook tyd opgeloste spektra, verkry dmv femtosekondespektroskopie, vergelyk. In pol^ere aprotiese, pol^ere protiese en nie-pol^ere oplosmiddels, isomeriseer die molekuul om die C=N dubbelbinding. Daar kan tussen die twee isomere onderskei word deur dat die een in oplossing in sy grondtoestand blou en die ander een oranje voorkom. Die isomerisering is’n fotogeinduseerde proses. Die optimering van die molekul^ere struktuur, absorpsiespektra, oplosmiddel-afhanklikheid, en potensiële energievlak metings van die molekuul word bestudeer. Die sterk/swak wisselwerking wat in pol^ere protiese/aprotiese oplosmiddels verskyn word geopenbaar deur die hoe/lae absorpsie van die sekond^ere bande van die molekules. Daar is gevind dat die absorpsiespektra van DPM bathochromies in oplosmiddels met hoë diëlektriese konstantes is. Vir die potensiële energievlak berekeninge van die grondtoestand word rigiede en ontspanne metodes gebruik waar laasgenoemde met gebroke simmetrie berekeninge verkry word. Van alle metodes wat vir berekeninge gebruik was, gee die B3LYP/CEP-31G metode die beste benadering aan eksperimentele data. Alle berekeninge word gedoen met twee bekende sagteware pakkette; Amsterdam Density Functional (ADF) en Gaussian, wat op twee verskillende DFT metodes gebaseer is. / ENGLISH ABSTRACT: Density functional theory is a useful computational tool in the understanding of molecular dynamics on potential energy surfaces. Starting with a prototype molecule formaldimine, the photochromic molecule dithizonatophenylmercury II (DPM) and a set of its photochromic derivatives, (involving substitutions of electron donating and electron withdrawing substituents at ortho, meta and para positions of the dithizonato phenyl rings), are studied through density functional calculation in comparison with steady state absorption spectra obtained from UV-Visible and femto second spectroscopy experiments. In polar aprotic, polar protic and non-polar solvents these molecules isomerise around C=N double bond chromophore, from orange electronic ground states to blue electronic ground states upon photo-excitation. We investigate the structural optimisations, the absorption spectra, the solvent dependence and the potential energy surface (PES) of these molecules. The strong (weak) interactions exhibited by the polar protic (aprotic) solvents used are revealed through high (low) absorbance in the secondary bands of these molecules. The absorption spectra of DPM are found to be bathochromic in solvents with high dielectric constants. For the ground state PES calculation we make use of rigid and relaxed methods, and the latter is obtained through broken symmetry calculation. Of all the methods used in calculation, B3LYP/CEP-31G method gives the best approximation to the experimental data. All calculations are done using the two renown software, Amsterdam Density Functional (ADF) and Gaussian, availing their different density functional methods.
17

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

January 1999 (has links)
Lau Kai-Chung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references. / Abstracts in English and Chinese. / Abstract / Acknowledgements / Table of Contents / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- The Gaussian-2 Method / Chapter 1.2 --- The G2 Method with Reduced M φller-Plesset Order and Basis Set / Chapter 1.3 --- The Gaussian-3 Method / Chapter 1.4 --- Our Modified G2 Methods / Chapter 1.5 --- Calculation of Thermodynamical Data / Chapter 1.6 --- Scope of the Thesis / Chapter 1.7 --- Remark on the Location of Transition Structures / Chapter 1.8 --- References / Chapter Chapter 2 --- A Gaussian-2 Study of the [C2H5O-] Potential Energy Surface and the Fragmentation Pathways of the Ethoxide Anion --- p.7 / Chapter 2.1 --- Introduction / Chapter 2.2 --- Theoretical Methods / Chapter 2.3 --- Results and Discussion / Chapter 2.3.1 --- Stable Isomers and TSs for the [C2H50-] Anions / Chapter 2.3.2 --- Fragmentation Pathways of the Ethoxide Anion (1-) / Chapter 2.4 --- Conclusions / Chapter 2.5 --- Publication Note / Chapter 2.6 --- References / Chapter Chapter 3 --- A Gaussian-2 Study of Isomeric C2H2N and C2H2N+ --- p.20 / Chapter 3.1 --- Introduction / Chapter 3.2 --- Theoretical Methods / Chapter 3.3 --- Results and Discussion / Chapter 3.3.1 --- The C2H2N and C2H2N+ Isomers / Chapter 3.3.2 --- The Cyanomethyl Radical (1) and Cation (1+) / Chapter 3.3.3 --- The Isocyanomethyl Radical (2) and Cation (2+) / Chapter 3.3.4 --- The lH-Azirinyl Radical (5) and Cation (5+) / Chapter 3.3.5 --- Other C2H2N and C2H2N+ Isomers / Chapter 3.3.6 --- The Unidentified C2H2N Isomer Formed in N + CH=CH2 / Chapter 3.4 --- Conclusions / Chapter 3.5 --- Publication Note / Chapter 3.6 --- References / Chapter Chapter 4 --- A Gaussian-2 Study of the Photoionization and Dissociative Photoionization Channels of Ethylene Oxide --- p.35 / Chapter 4.1 --- Introduction / Chapter 4.2 --- Theoretical Methods / Chapter 4.3 --- Results and Discussion / Chapter 4.3.1 --- Bond Cleavage Reactions / Chapter 4.3.2 --- Dissociation Channels Involving Transition Structure(s) / Chapter 4.4 --- Conclusions / Chapter 4.5 --- Publication Note / Chapter 4.6 --- References / Chapter Chapter 5 --- A Gaussian-2 Study of the Photoionization and Dissociative Photoionization Channels of Propylene Oxide --- p.47 / Chapter 5.1 --- Introduction / Chapter 5.2 --- Theoretical Methods / Chapter 5.3 --- Results and Discussion / Chapter 5.3.1 --- Bond Cleavage Reactions / Chapter 5.3.2 --- Dissociation Channels Involving Transition Structure(s) / Chapter 5.4 --- Conclusions / Chapter 5.5 --- Publication Note / Chapter 5.6 --- References / Chapter Chapter 6 --- A Gaussian-3 Study of the Thermochemistry of Chlorofluoromethanes (CFnCl4-n) and Their Cations (CFnCl4_n+), n =0-4 --- p.61 / Chapter 6.1 --- Introduction / Chapter 6.2 --- Theoretical Methods / Chapter 6.3 --- Results and Discussions / Chapter 6.3.1 --- Heats of Formation of Chlorofluoromethanes and Their Cations / Chapter 6.3.2 --- Ionization Energies of Chlorofluoromethanes / Chapter 6.3.3 --- Proton Affinities of Chlorofluoromethanes / Chapter 6.4 --- Conclusions / Chapter 6.5 --- Publication Note / Chapter 6.6 --- References / Chapter Chapter 7 --- "A Gaussian-2 and Gaussian-3 Study of the Energetics and Structures of Cl2On and Cl2On+, n = 1,4, 6,and7" --- p.69 / Chapter 7.1 --- Introduction / Chapter 7.2 --- Theoretical Methods / Chapter 7.3 --- Results and Discussion / Chapter 7.3.1 --- Cl20 and Cl20+ / Chapter 7.3.2 --- Cl204 and Cl204+ / Chapter 7.3.3 --- Cl206 and Cl206+ / Chapter 7.3.4 --- Cl207 and Cl207+ / Chapter 7.4 --- Conclusions / Chapter 7.5 --- Publication Note / Chapter 7.6 --- References / Chapter Chapter 8 --- Conclusions --- p.81 / Chapter Appendix A --- The Gaussian-n (n = 1 - 3) Theoretical Models --- p.82 / Chapter A.1 --- The G1 and G2 theories / Chapter A.2 --- The G2(MP2) theory / Chapter A.3 --- "The G2(MP2,SVP) theory" / Chapter A.4 --- The G3 theory / Chapter Appendix B --- "Calculation of Enthalpy at 298 K, H298" --- p.86
18

Methods for calculating rates of transitions with application to catalysis and crystal growth /

Henkelman, Graeme, January 2001 (has links)
Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (p. 129-136).
19

A quantum equation of motion for chemical reaction systems on an adiabatic double-well potential surface in solution based on the framework of mixed quantum-classical molecular dynamics

Okazaki, Susumu, Yamada, Atsushi 01 1900 (has links)
No description available.
20

Development of Mild Methods for Selective Covalent Functionalization of Graphene

Lundstedt, Anna January 2017 (has links)
This thesis discusses methods for the comparatively mild covalent functionalization of graphene. Several graphene models were investigated: polycyclic aromatic hydrocarbons (PAHs), chemical vapor deposition (CVD)-graphene on SiO2/Si substrate, graphite foil, graphite flakes, kish graphite and highly oriented pyrolytic graphite. The PAHs were viewed as graphene edge analogs with the following molecules representing different edge motifs: pyrene, perylene, benzo[a]pyrene, benzo[e]pyrene, triphenylene, acenapthylene, and anthracene. Ozone was used in combination with different solvents to functionalize PAHs, graphite, and CVD-graphene on SiO2/Si. Ozonation in water or methanol resulted in trapping of the carbonyl oxide intermediate that was formed in the reaction, producing a variety of functional groups. Ozonation in hydrogen peroxide solution with sonication promoted radical formation, possibly resulting in edge-oxidation of graphite. The regioselectivity for addition reactions (ozonolysis) and electrophilic aromatic substitution reactions with graphene edges is discussed. To achieve functionalization of the basal plane of graphite or graphene, white light irradiation was used in combination with several transfer hydrogenation reagents. Formic acid treatment under irradiation resulted in the expected hydrogenation, whereas iso-propanol treatment resulted in iso-propanol attachment to the graphene. The developed methods provide opportunities for graphene functionalization without the need for metal based reagents or harsh conditions.

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