posted on 2015-11-19, 08:48authored byPaul. Wellings
The work in this thesis has two distinct themes. The development of apparatus and computer programs to measure real-time first-order rate constants, and the use of this system in the investigation of reactions of iron(II) complexes in aqueous solvent mixtures. Two computers, a DEC pdpII/03 and a CDC Cyber 73,were used in conjunction with a spectrophotometer to collect absorbance data and calculate rate constants for the kinetic studies described below. The second-order rate constant for the reaction of nucleophilic ions at low-spin iron(II) complexes is sensitive to the nature of the aqueous environment. An investigation was carried out to establish the effect of ligand variation on the reactivity with hydroxide ions in methanol-water mixtures. Kinetic and spectroscopic evidence is presented to support the postulate that ligand substituted intermediates are present in the reaction of the trisferrozine iron(II) anion with hydroxide and cyanide ions in aqueous mixtures. Though there have been many kinetic studies in binary solvent media and in salt solutions, there has been little investigation of ternary solvent mixtures, The third kinetic study in this thesis looks at such mixtures using reaction of known mechanism.