Date of Award

1992

Document Type

Dissertation

Degree Name

Doctor of Philosophy (PhD)

Department

Chemistry

First Advisor

Leslie G. Butler

Abstract

Solid-state NMR spectroscopy has been used to obtain information about electronic structure and molecular geometry for some organometallic complexes. The principal elements of the $\sp{13}$C chemical shielding tensor for a dimetallocyclopropane unit and three square-planar metal cyanides have been determined from a nonlinear least-squares fit of the chemical shift powder pattern. For the dimetallocyclopropane unit, the orientation of the chemical shielding tensor with respect to the molecular axis has been assigned based on the dipolar coupling tensor. The principal elements of the $\sp{31}$P chemical shielding tensor for three binuclear platinum diphosphite complexes have been obtained from a Herzfeld-Berger graphical analysis of the MAS spectrum. The paramagnetic contribution to the $\sp{13}$C chemical shielding tensor is related to the metal-carbon bonding interaction. The deuterium quadrupole coupling constants and the asymmetry parameters for six bridging metal hydride complexes have been acquired from a nonlinear least-squares fit of the deuterium powder pattern. The relationships between the quadrupole coupling constant and the M-H bond length and between the asymmetry parameter and the M-H-M bond geometry are discussed on the basis of a point charge model. Deuterium MAS spectra for four simple inorganic compounds and two physical mixtures have been obtained. The resolution of two inequivalent deuterium sites in the mixtures is described by the quality of the fit between experimental and calculated MAS spinning sidebands intensities. A fitting method using a Levenberg-Marquardt nonlinear least-squares algorithm is described for the extraction of the NMR parameters from the solid-state NMR powder patterns.

Pages

207

Available for download on Wednesday, December 01, 9999

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