STUDIES ON THE RESONANCE-RAMAN AND INFRAR ED-SPECTRA OF CLUSTER COMPOUNDS WITH MIXED-VALENCE MO(W) ATOMS, [ET(4)N](2)[((CO)(4)M)(X)M'S-4] [X=1,2, M=MO(0), W(0), M'=MO(VI), W(VI)]

The Resonance-Ramsn and Infrared spectra of series of cluster compound s, [{(CO)(4)M}(x)-M'S-4](2-)[x=1 or 2; M=Mo(0) or W(0); M'=Mo(VI) or W (VI)] have been investigated. Besides the characteristic frequencies o f nu(CO), nu(M(VI)-S(b)), nu(M(VI)-S(t)), nu(M(0)-C) and delta(M(0)-C- O) were assigned, The assignment of nu M((0)-S(b)) and nu(M(0)-M(VI)) were emphatically discussed. The relationship between Delta nu [nu(M(V I)-S(b))-nu(M(0)-S(b))] and M(0)-->M(VI) charge transfer were demonstr ated by their IR spectra. The results from the studies on the Resonanc e-Raman spectra indicate that there evidently are couplings between th e S(b)-->Mo(0) charge transfer and M(0)-->Mo(VI) charge transfer in [( CO)(4)MS(2)MoS(2)](2-) and [(CO)(4)MoS2MoS2Mo(CO)(4)](2-), between S(b )-->W(VI) and M(0)-->W(VI) charge transfer and between S(t)-->W(VI) an d M(0)-->W(VI) charge transfer in [(CO)(4)MS(2)WS(2)](2-) . This impli es that the extensive electron delocalization exists in these cluster compounds with mixed-valence metal atoms and the electron delocalizati on in the dinuclear clusters is stronger than that in the trinuclear c lusters.