Date of Award
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 13C 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 13P chemical shielding tensor for three binuclear platinum diphosphite complexes have been obtained from a Herzfeld-Berger graphical analysis of the MAS spectra. The paramagnetic contribution to the 13C chemical shielding tensor is related to the metalcarbon 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 sideband 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.
Kim, Ae Ja, "Solid-State NMR Studies of Organometallic Complexes" (1992). LSU Historical Dissertations and Theses. 8369.