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Timken, Hye Kyung Cho 2014-12-15T23:19:03Z 2014-12-15T23:19:03Z 10000-01-01 1987 1987 Solid-state nuclear magnetic resonance (NMR) has been used to study a variety of systems of chemical, physical, and geological interest, including zeolites, metasilicates, and semiconductors. Among the nuclei studied were $\sp $O, $\sp{27}$Al, $\sp{69}$Ga and $\sp{71}$Ga. The general motivations for this research were to broaden solid-state NMR into new nuclei, especially quadrupolar nuclei, and to examine how quadrupolar NMR can be used as a structural tool. The research involved several applications, brief descriptions of which are presented below. Quadrupolar echo techniques were applied in order to resolve chemically non-equivalent sites in solids which have nearly identical chemical shifts. Oxygen-17 NMR studies of zeolites and related systems demonstrated that the $\sp $O NMR spectra of these systems consist of resonances from chemically distinct oxygen species, Si ($\sp $O) Si and Si ($\sp $O) Al for aluminosilicates; Si ($\sp $O) Si and Si ($\sp $O) Ga for gallosilicates; and Al ($\sp $O) P for the AlPO$\sb{4}$ zeolite analogs. From $\sp{69}$Ga and $\sp{71}$Ga NMR studies of gallium analog zeolites we have characterized the framework gallium sites (Ga(OSi)$\sb{4}$), and have obtained NMR parameters essentially by carrying out a "frequency dependence" study at one magnetic field strength by observing the different apparent chemical shifts of $\sp{69}$Ga and $\sp{71}$Ga. We have measured and interpreted the variable-temperature spin-lattice relaxation times (T$\sb{1}$) of $\sp{27}{\rm Al}$ in zeolites. The major relaxation mechanism is due to the quadrupolar interaction. For hydrated zeolites, the motions of the hydrated water in zeolites gives rise to a fluctuating electric field gradient at the framework Al nuclear sites. From $\sp $O NMR studies of a series of alkaline earth metasilicates, we have characterized the different oxygen sites encountered (one bridging oxygen and two distinct non-bridging oxygens). Finally, we have applied $\sp{69}$Ga and $\sp{71}$Ga NMR to a series of gallium-containing III-V semiconductors. By applying the magic-angle sample-spinning technique, we can selectively remove some specific linebroadening mechanisms and the contribution of each mechanism (dipolar, first-order and second-order quadrupolar, pseudodipolar, and exchange interaction) may be more accurately estimated. Made available in DSpace on 2014-12-15T23:19:03Z (GMT). No. of bitstreams: 1 8721769.pdf: 6124738 bytes, checksum: ba5801badbd5278565130c41a2591a35 (MD5) Previous issue date: 1987 Embargo set by: Seth Robbins for item 70547 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs U of I Only 213 p. Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1987. http://hdl.handle.net/2142/70381 (UMI)AAI8721769 Chemistry, Physical Solid-State Nuclear Magnetic Resonance Studies of Quadrupolar Nuclei in Inorganic Systems (Nmr) text Chemistry Chemistry University of Illinois at Urbana-Champaign Dissertation Ph.D.