Evidence for strong mixing between the LC and MLCT excited states in bis(2-phenylpyridinato-C2,N')(2,2'-bipyridine)iridium(III)

摘要: The well-resolved absorption, excitation, and luminescence spectra of [Ir(ppy)2bpy]+ (ppyH = 2-phenylpyridine, bpy 2,2'-bipyridine) in different media at cryogenic temperatures are presented. In solutions glasses ambient temperature the lowest energy excited state corresponds to an Ir - charge-transfer excitation whereas crystalline host lattice [Rh(ppy)2bpy]PF6 21 450 cm-1 is assigned a 37r-r* localized on cyclometalating ppy- ligands. next higher has shifted 820 cm-', only 300 cm-I above 3LC state. close proximity 3MLCT states large spin-orbit coupling constant Ir3+ induce strong mixing character into states, resulting increased oscillator strengths, reduced lifetimes, short axis polarized transitions, zero-field splitting 10-15 cm-1.