SOME CHARACTERISTICS OF INFRARED AND RAMAN-SPECTRA AND BONDING OF A SERIES OF LANTHANIDE COMPLEXES WITH L-PROLINE

The crystalline lanthanide complexes (except Ce and Pm) with proline w ere synthesized. The general formula of [Ln(Pro)(2)(H2O)(4)](3)(ClO4)( 3) of the complexes were obtained from chemical analysis, elemental an alysis, TG-DTA analysis and electrical conductivity. Infrared spectra reveal a considerable shift of the symmetric co(2) stretching mode fro m lower to higher energies in the lanthanide complexes and a decrease of Delta nu(Delta nu=nu(coo-)(as)-nu(coo-)(5)) from 212 cm(-1) in prol ine to about 167 cm(-1) in the complexes. The peak mean 405cm(-1) in t he Raman spectra varies with the total orbital angular momentum of the lanthanide ions in the ground states, exhibiting a profile of an ''in clined w''. These spectral features in the IR and Raman spectra were r egarded as strong evidences of Ln-O bending. The peak near 405cm(-1) w as assigned as the Ln-O stretch modes.