RESONANCE RAMAN-SPECTRA OF IRON (II) 2,2'-BIPYRIDYL COMPLEXES

The resonance Raman effect is reported for the bipyridyl ligand vibrations in the complexes {Fe(bipy)3}+2, {Fe(bipy)2(CN)2} and {Fe(bipy)(CN)4}−2. The Raman spectra were obtained using exciting laser line frequencies coincident with the visible metal–ligand charge transfer absorption bands. The identity of the resonantly enhanced Raman bands is correlated with the nature of the absorption bands. The resonantly enhanced excitation profiles of the bipyridyl vibrations are analyzed in terms of the theory of resonance Raman scattering. The results indicate that the high frequency components of these bands are primarily due to a superposition of the vibrational progressions of the symmetric ligand stretching modes and not due to additional charge transfer absorptions. Copyright © 1979 Heyden & Son Ltd.