Molecular Electronic Structure via Photoelectron Imaging Spectroscopy

Persistent Link:
http://hdl.handle.net/10150/301677
Title:
Molecular Electronic Structure via Photoelectron Imaging Spectroscopy
Author:
Culberson, Lori
Issue Date:
2013
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Embargo:
Release after 29-Jan-2014
Abstract:
This dissertation explores the use of photoelectron imaging spectrometry to probe the molecular electronic structure of various chemical systems, with an emphasis on photoelectron angular distributions. Experimental ion generation, mass selection, laser photodetachment, and photoelectron ion imaging were all done in a photoelectron imaging spectrometer described in detail. Results from simplistic systems, OH- and CH-, are used to illustrate the general and fundamental capabilities of imaging spectroscopy and angular distributions. This illustration is then expanded when both qualitative and quantitative analyses of photoelectron angular distributions are used to aid in the understanding of the electronic structure of several heterocyclic aromatic systems. First a qualitative analysis aids in the exploration of the electronic structure of thiophenide, C₄H₃S⁻, and furanide, C₄H₃O⁻. Ground and excited C₄H₃S and C₄H₃O radical states are observed, and bond dissociation energies are defined. Next, a new model used to qualitatively analyze photoelectron angular distributions resulting from mixed s - p hybrid states is presented and applied to detachment from pyridinide, C₅H₄N⁻; as a benchmark system. Before further exploring this model, the synthesis of several deuterated heterocyclic compounds is presented in order to determine the experimentally produced systems in our experimental setup. The electronic structure of the resultant molecules oxazolide, C₃H₂NO⁻, and thiazolide, C₃H₂NS⁻; are then investigated. Using this new qualitative model, the mixed s - p states model, to evaluate the angular distributions of the systems, the hybridization of the anion molecular orbitals is probed. Comparison of the photoelectron angular distributions that are modeled for each heterocyclic aromatic system yields several trends relating aromatic stabilization, molecular hybridization, and bond dissociation energies. A new qualitative model is then presented to evaluate photoelectron angular distributions resulting from mixed p - d states and applied to detachment from NO⁻. Finally, new ideas and directions are proposed.
Type:
text; Electronic Dissertation
Keywords:
aromaticity; gas-phase; hybrid orbitals; photoelectron imaging; spectroscopy; Chemistry; anions
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Graduate College; Chemistry
Degree Grantor:
University of Arizona
Advisor:
Sanov, Andrei

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleMolecular Electronic Structure via Photoelectron Imaging Spectroscopyen_US
dc.creatorCulberson, Lorien_US
dc.contributor.authorCulberson, Lorien_US
dc.date.issued2013-
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.releaseRelease after 29-Jan-2014en_US
dc.description.abstractThis dissertation explores the use of photoelectron imaging spectrometry to probe the molecular electronic structure of various chemical systems, with an emphasis on photoelectron angular distributions. Experimental ion generation, mass selection, laser photodetachment, and photoelectron ion imaging were all done in a photoelectron imaging spectrometer described in detail. Results from simplistic systems, OH- and CH-, are used to illustrate the general and fundamental capabilities of imaging spectroscopy and angular distributions. This illustration is then expanded when both qualitative and quantitative analyses of photoelectron angular distributions are used to aid in the understanding of the electronic structure of several heterocyclic aromatic systems. First a qualitative analysis aids in the exploration of the electronic structure of thiophenide, C₄H₃S⁻, and furanide, C₄H₃O⁻. Ground and excited C₄H₃S and C₄H₃O radical states are observed, and bond dissociation energies are defined. Next, a new model used to qualitatively analyze photoelectron angular distributions resulting from mixed s - p hybrid states is presented and applied to detachment from pyridinide, C₅H₄N⁻; as a benchmark system. Before further exploring this model, the synthesis of several deuterated heterocyclic compounds is presented in order to determine the experimentally produced systems in our experimental setup. The electronic structure of the resultant molecules oxazolide, C₃H₂NO⁻, and thiazolide, C₃H₂NS⁻; are then investigated. Using this new qualitative model, the mixed s - p states model, to evaluate the angular distributions of the systems, the hybridization of the anion molecular orbitals is probed. Comparison of the photoelectron angular distributions that are modeled for each heterocyclic aromatic system yields several trends relating aromatic stabilization, molecular hybridization, and bond dissociation energies. A new qualitative model is then presented to evaluate photoelectron angular distributions resulting from mixed p - d states and applied to detachment from NO⁻. Finally, new ideas and directions are proposed.en_US
dc.typetexten_US
dc.typeElectronic Dissertationen_US
dc.subjectaromaticityen_US
dc.subjectgas-phaseen_US
dc.subjecthybrid orbitalsen_US
dc.subjectphotoelectron imagingen_US
dc.subjectspectroscopyen_US
dc.subjectChemistryen_US
dc.subjectanionsen_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.disciplineChemistryen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorSanov, Andreien_US
dc.contributor.committeememberMonty, Oliveren_US
dc.contributor.committeememberBrown, Michaelen_US
dc.contributor.committeememberStafford, Charlesen_US
dc.contributor.committeememberSanov, Andreien_US
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