Structural and theoretical studies of organometallic complexes.
This thesis reports structural studies using X-ray crystallography and Extended X-ray Absorption Fine Structure (EXAFS) spectroscopy and theoretical studies using Extended Hükel Molecular Orbital (EHMO) calculations and the Cambridge Structural Database (CSD) on a wide range of organometallic compounds.
Crystal structure determinations have been undertaken on the following complexes: [Bi(SCN)(Mo(CO)3Cp)2] (1), [BiBr(Ph)(Mo(CO(3Cp)] (2), [PPN][BiCl3(Mo(CO)3Cp)] (3), [PPh4][BiBr2(Mo(CO)3Cp)2] (4), [BiPh2(HMPA)2][BF4] (5) and K[K18-C-6]2[Bi(SCN)6] (6). Complexes (1) and (2) form one-dimensioanl polymeric chains via thiocyanate and bromine bridging respectively, illustrating the Lewis acidity of the bismuth (III) centre. Complex (3) dimerises in the solid state to from a Bi2Cl2 ring via chlorine bridging. Complexes (4) and (5) exist as separate monomeric cationic and anionic units with no intermolecular interactions. Complex (6) consists of a K with six intermolecular contacts, four inplant K---N contacts from independent octahedral [Bi(SCN)6]3- units and two K---O contacts form a K-crown ether above and below the plane.
EXAFS studies have been undertaken on a wider range of systems, including (i) the rearrangement of the spiked triangular cluster [Ru3Pt(-H))(4-2-CC^tBu)(CO)_9(dppe)] to the butterfly cluster [Ru_3Pt (4-2-CCH^tBu)(CO)_9(dppe)] followed over a period of 12 hours, (ii) cobalt doped silica-gel glasses and (iii) thiolato and selenato complexes of cadmium and zinc. One of the main aims of the EXAFS studies is to determine how the complexes under investigation aggregate in the solid state and to what extent that association breaks down in solution.