Thesis (Ph. D.)--University of Wisconsin--Madison, 1970. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1982. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 275-285).

Thesis (Ph.D.)-University of KwaZulu-Natal, Durban, 2009. / Full text also available online. Scroll down for electronic link.

Thesis (Ph. D.)--University of Texas at Austin, 2005. / Supervisor: Keith P. Johnston. Vita. Includes bibliographical references.

The variation of the viscosity of aqueous and non-aqueous electrolyte solutions with salt concentration has been studied and the results interpreted in terms of a number of mathematical models. The effects of ion-association on the viscosity of electrolyte solutions has been investigated by measuring the viscosity of aqueous solutions of some thallous salts. The viscosities of alkali halide salts in formamide have been determined over a range of temperatures and new methods for the division of viscosity B-coefficients into ionic contributions have been proposed. The results of these studies have been interpreted in terms of the ion-solvent interactions. The intermolecular interactions present in binary liquid mixtures of formamide with methanol, ethanol propan-l-ol and butan-l-ol have been studied by viscosity measurements over the complete concentration range. Finally the usefulness of time domain dielectric spectroscopy in solute-solvent interaction studies has been briefly investigated.

Rate constants for the pyridine catalyzed ionic decomposition of t-butylperoxyformate (TBF) are measured in 15 non-hydroxylic solvents. The second order rate constants varied by a factor of 40 from the "slowest" solvent, tetra-chloroethylene, to the "fastest", 1,2-dichloroethahe. Ten different empirical equations are found and their ability to correlate the rate constants with bulk solvent properties is compared. The best of the ten equations involves the polarizability and dipole moment of the solvent as follows. log krel = 1.207 (no²-1/no²+2) + 3.99 μ + 0.003 -3 The rate constants for TBF decomposition in other non-hydroxylic solvents are calculated by the empirical equations and are compared with values previously reported. The average deviation of the log k is 0.22. The rate constants for the reaction of methyl iodide with triethylamine are calculated from solvent properties and the values compared to literature values. In this case the average deviation of the log k is 0.31. / Science, Faculty of / Chemistry, Department of / Graduate

Kinetic studies of a number of interesting and significant reactions involving activation of hydrogen, olefins, oxygen and carbon monoxide by solutions of rhodium complexes containing sulphur and/or chloride ligands are described. The cis 1,2,3-trichlorotris(diethylsulphide)rhodium (III) complex, RhCl(EtS₃and the corresponding dibenzyl sulphide complex, RhCl₃(Bz₂S)₃in N,N -dimethylacetamide (DMA) solution were found to be effective catalysts for the homogeneous hydrogenation of maleic, fumaric and trans-cinnamic acids. The kinetic data are consistent with a dissociation of a sulphur ligand prior to the hydrogen reduction of rhodium (III) to rhodium (I). The rhodium (I) is stablized in solution by rapid complexing with the olefin to produce a Rh¹(olefin)(Ln) complex (L = auxiliary ligands) which then reacts with H₂ in a rate determining step to produce the saturated paraffin and rhodium (I). In some instances, more complex kinetics resulted when one of the auxiliary ligands in the Rh¹ (olefin)(Ln) complex dissociates prior to reaction with H(2); a unique apparent zero order in catalyst concentration has been observed. Isomerization was observed in the RhCl(EtS)₃catalyzed hydrogenation of fumaric acid and a mechanism involving rhodium (III) alkyl intermediate seems likely. The cyclooctene complex, [Rh(C8H14)₂C1], in DMA was found to be a convenient source for preparing rhodium (I) complexes "in situ" by adding the desired ligands, for example, chloride or diethyl sulphide. Kinetic data obtained using such solutions are in good agreement with the hydrogenation data obtained by starting from the corresponding rhodium (III) complexes. This result confirms that rhodium (I) intermediates are involved in the catalytic hydrogenation starting from rhodium (III) complexes. During studies to investigate the effect of solvent on catalytic hydrogenation of olefins by rhodium (III) complexes, dimethyl sulphoxide (DMSO) was found to be catalytically reduced by hydrogen to dimethyl sulphide and water in the presence of RhCl(EtS)₃ and RhCl‧3H2O. The kinetics were consistent with a rate determining heterolytic splitting of H₂ by Rh(III)(DMSO) to produce Rh[III](DMSO)H¯ which then decomposes to the products in a fast step. RhCl₃‧3H₂O also catalyzed the oxidation of DMSO to dimethyl sulphone using a mixture of oxygen and hydrogen. The solution of [Rh(C8H14)₂C1]₂ in DMA containing LiCl was found to be a versatile catalyst, for besides the activation of hydrogen and olefins, oxygen and carbon monoxide could also be activated. The formation of a rhodium (I) molecular oxygen complex, Rh(I)(O2) and a subsequent catalyzed oxidation of the DMA solvent and cyclooctene were studied in detail. The formation of the Rh(I)(O2) complex appears to be irreversible. An E.S.R. signal, possibly due to species such as Rh(II)(O2¯) was also observed. The kinetics of the oxidation suggest the equilibrium formation of the Rh(I)(O2) complex followed by a rate determining step to give the products. A free radical mechanism seems likely. Solutions of [Rh(C8H14)₂C1]₂ in LiCl/DMA readily reacted with carbon monoxide to form a Rh(I)(CO)₂ species. A solution of the oxygen complex was converted more slowly to the Rh(I)(CO)₂ species in a reaction whose observed rate was determined by the dissociation of the coordinated oxygen. Preliminary studies indicated that a mixture of CO and O₂ is converted catalytically to CO₂ by a solution of [Rh(C8H14)₂C1]₂ in LiCl/DMA. / Science, Faculty of / Chemistry, Department of / Graduate

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