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Robert G. Griffin. Maus, Douglas C.(Douglas Charles) Massachusetts Institute of Technology. Department of Chemistry. Massachusetts Institute of Technology. Department of Chemistry 2005-08-18T17:24:22Z 2005-08-18T17:24:22Z 1996 1996 Thesis: Ph. D., Massachusetts Institute of Technology, Dept. of Chemistry, 1996 Cataloged from PDF of thesis. Microfiche contains the reproduction of the print thesis. Includes bibliographical references (page 152). Nuclear Magnetic Resonance (NMR) spectroscopic data often involve spatial and spin dynamics and interference phenomena between the two. Experimental results are presented which demonstrate several of these phenomena and exploitation of these anomalies to acquire and improve knowledge regarding relevant chemistry. In some cases numerical analysis of such data are illustrated for obtaining quantitative rates of molecular dynamics. First, the dynamics of methyls bonded to the metals Tungsten and Tantalum are examined. In the case of Tungsten. an interference between methyl dynamics and proton decoupling is studied, whereas in the Tantalum instance, interference between molecular dynamics and Magic Angle Spinning (MAS) is examined. Agostic interactions had been hypothesized to exist in both compounds, but the unusual molecular dynamics are explainable without invoking a relation to such interactions. Further, no evidence is found to support the existence agostic bonds from examination of X-ray crystal data. Next. the spin dynamics in high resolution solid state proton systems diluted by deuterium is examined. In this case techniques such as Rotational Resonance and Radio-Frequency driven Dipolar Recoupling (RFDR) are employed to counteract the averaging of dipole couplings induced by MAS. The numerical analysis of such data in systems in which internuclear distances of interest are not identical but rather statistically distributed is discussed. Finally, a technique which may improve the sensitivity of NMR experiments is demonstrated. Dynamic Nuclear Polarization (DNP) is adapted to solid state MAS experiments and shown to enhance the signal intensity of a biomolecule, T4-lysozyme, by a factor of ~50. The necessary conditions for application of this technique to solid state NMR is discussed. by Douglas C. Maus. Ph.D. Ph.D. Massachusetts Institute of Technology, Dept. of Chemistry 152 leaves eng Massachusetts Institute of Technology System requirements: Microfiche reader machine. MIT theses may be protected by copyright. Please reuse MIT thesis content according to the MIT Libraries Permissions Policy, which is available through the URL provided. http://dspace.mit.edu/handle/1721.1/7582 Chemistry. Molecular and spin dynamics in solid state nuclear magnetic resonance spectroscopy Thesis 36267295 application/pdf 2021-02-02T15:37:26Z Publication unknown unknown <Publication xmlns="https://www.openaire.eu/cerif-profile/1.1/" id="e8354f97-aa5d-4d67-844a-a090710422e3"> <Type xmlns="https://www.openaire.eu/cerif-profile/vocab/COAR_Publication_Types">http://purl.org/coar/resource_type/c_1843</Type> <Language>eng</Language> <Title>Molecular and spin dynamics in solid state nuclear magnetic resonance spectroscopy</Title> <PublishedIn> <Publication> </Publication> </PublishedIn> <PublicationDate>1996</PublicationDate> <Authors> <Author> <DisplayName>Maus, Douglas C.(Douglas Charles)</DisplayName> <Affiliation> <OrgUnit> </OrgUnit> </Affiliation> </Author> </Authors> <Editors> </Editors> <Publishers> <Publisher> <DisplayName>Massachusetts Institute of Technology</DisplayName> <OrgUnit /> </Publisher> </Publishers> <License>http://dspace.mit.edu/handle/1721.1/7582</License> <Keyword>Chemistry.</Keyword> <Abstract>Nuclear Magnetic Resonance (NMR) spectroscopic data often involve spatial and spin dynamics and interference phenomena between the two. Experimental results are presented which demonstrate several of these phenomena and exploitation of these anomalies to acquire and improve knowledge regarding relevant chemistry. In some cases numerical analysis of such data are illustrated for obtaining quantitative rates of molecular dynamics. First, the dynamics of methyls bonded to the metals Tungsten and Tantalum are examined. In the case of Tungsten. an interference between methyl dynamics and proton decoupling is studied, whereas in the Tantalum instance, interference between molecular dynamics and Magic Angle Spinning (MAS) is examined. Agostic interactions had been hypothesized to exist in both compounds, but the unusual molecular dynamics are explainable without invoking a relation to such interactions. Further, no evidence is found to support the existence agostic bonds from examination of X-ray crystal data. Next. the spin dynamics in high resolution solid state proton systems diluted by deuterium is examined. In this case techniques such as Rotational Resonance and Radio-Frequency driven Dipolar Recoupling (RFDR) are employed to counteract the averaging of dipole couplings induced by MAS. The numerical analysis of such data in systems in which internuclear distances of interest are not identical but rather statistically distributed is discussed. Finally, a technique which may improve the sensitivity of NMR experiments is demonstrated. Dynamic Nuclear Polarization (DNP) is adapted to solid state MAS experiments and shown to enhance the signal intensity of a biomolecule, T4-lysozyme, by a factor of ~50. The necessary conditions for application of this technique to solid state NMR is discussed.</Abstract> <Access xmlns="http://purl.org/coar/access_right" > </Access> </Publication>