화학공학소재연구정보센터
Inorganic Chemistry, Vol.34, No.26, 6421-6422, 1995
Application of Resonance Raman-Spectroscopy to Electronic-Structure in Metal-Complex Excited-States - Excited-State Ordering and Electron Delocalization in Dipyrido(3,2-A-2’,3’-C)Phenazine (Dppz) - Complexes of Re(I) and Ru(II)
From excitation-dependent resonance Raman measurements on [Ru(dmb)(2)(dppzj](2+) (dmb is 4,4’-dimethyl-2,2’-bipyridine : dppz is dipyrido[3,2-a:2’,3’-c]phenazine) in CH3CN a metal-to-ligand charge transfer (MLCT) band at 450 nm is Ru-II(d pi) --> dmb(pi*) in character with Ru-II(d pi) --> dppz(pi*) appearing as a shoulder at similar to 490 nm (bpy is 2,2’-bipyridine). Excited state measurements show that dppz is the acceptor ligand and point to delocalization of the excited electron over the entire ligand framework. From transient resonance Raman measurements on fac-[Re(dppz)(CO)(3)-(PPh(3))](+) (PPh(3) is triphenylphosphine) and fac-[Re(dppz)(CO)(3)Cl], the lowest excited state in both is dppz-localized (3) pi pi* in character even though the chloro complex is a MLCT emitter.