VIBRATIONAL SPECTROSCOPY AND SOLID-STATE CHEMISTRY

Some aspects of the application of vibrational spectroscopy to problems of solid state chemistry are reviewed and discussed in the light of the work carried out in the laboratory of inorganic structural chemistry of the University of Liège. The following topics have been considered: Methods of interpretation of the spectra: isomorphic replacements and the vibrational behaviour of solid solutions; isotopic replacement, its possibilities and limitations. Local symmetry of a complex anion: vibrational behaviour of "dilute" solid solutions. Correlations between the coordination of a cation, the cation-oxygen distances and the cation-oxygen vibrational frequencies; application to compounds with unknown structure; detailed discussion of the specific case of titanium in titanates and titano-silicates. Order-disorder phenomena; interest of the simultaneous use of vibrational spectroscopy and X-ray diffraction. Glasses; structural analogies or differences between a crystalline compound and the corresponding glass. Dual structural role of lead in lead borate glasses. Metamict state; evidence of intermediate stages during a recrystallisation process. © 1990.