Stuctural aspects of certain inorganic solid-state materials.

An introduction to the theory of phase transitions is presented which includes both thermodynamic and structural treatments of phase transitions. A literature review of the role of vibrational spectroscopy in the investigation of phase transitions is given for the period covering 1978 to 1987. Full experimental procedures are outlined covering the design and use of the diamond anvil cell (d.a.c.) utilised in the experimental investigations undertaken in this work. The single crystal structure of Re(C0)5I has been determined by x-ray diffraction techniques, together with a structural comparison with the other members of the Re(C0)5X series (where X = Cl, Br). Following on from the above, a vibrational investigation of the M(C0)5X series (where M = Mn, Re; X = Cl, Br, I) is presented. An accompanying high-pressure Raman investigation of Re(CO)5I is also shown. The group I metal halate series MXO3 (where M = K, Na; X = Cl, Br) have been investigated by infrared and Raman spectroscopy. High-pressure data are available for some of the series. In continuation of earlier work a phase structural investigation, at high-pressure, of KCIO3 was performed using synchrotron radiation at the SRS, Daresbury.