FT RAMAN AND FTIR SPECTRA OF FOUR DISELENITES PbSe2O5, CdSe2O5, MnSe2O5 and Cr2(Se2O5)3
The vibrational spectra of Lead diselenite, Cadmium diselenite, Manganese diselenite and chromium diselenite have been recorded and analysed on the basis of vibrations due to [Formula: see text] ion. The observed spectra clearly indicate the presence of diselenite group in all these compounds. The spectral analysis confirms the orthorhombic nature of MnSe 2 O 5 as suggested by Koskenlinna et al. A large number of vibrational bands in the symmetric stretching region of PhSe 2 O 5 is due to the existence of different Se-O bond lengths. From the spectra it can be seen that the anion is highly distorted angularly in chromium compound. This high distortion in all modes confirms the presence of three crystallographically distinct diselenite groups in chromium compound.