Vibrational spectra and normal vibrations of rare earth formates

The infrared and laser Raman spectra of rare earth formates and deutero formates are presented. A normal coordinate analysis of gadolinium formate, for which structural data are available, is carried out. Using the results of normal coordinate analysis, low frequency Raman spectra and far infrared spectra, it is shown that the earlier assignments of the skeletal modes have to be completely revised. By a careful study of the formate and deutero formate compounds, Fermi resonance in the CO stretching region is also established. Correlation between the C---H stretching frequency in formates with their covalent character is shown