DFT/TDDFT studies on electronic absorption and emission spectra of [Ru(bpy)2(L)]2+ (LÂ =Â pip, o-mopip and p-mopip) in aqueous solution

The electronic absorption spectra and emission spectra of a series of Ru(II) polypyridyl complexes [Ru(bpy)2(L)]2+ (bpy = 2,2-bipyridine; L: pip = 2-phenylimidazo[4,5-f][1,10]-phenanthroline, o-mopip = 2-(2-methoxyphenyl)imidazo[4,5-f][1,10]-phenanthroline and p-mopip = 2-(4-methoxyphenyl)imidazo[4,5-f][1,10]-phenanthroline) (1-3) in aqueous solution have been calculated, simulated and explained using DFT/TDDFT methods as well as conductor-like polarizable continuum model (CPCM). The calculated results show that the obtained absorption and emission spectra in aqueous solution with DFT/TDDFT method combined with CPCM model are comparable with the experimental observations, and the substituent on main ligand (pip) plays a valuable role in modifying the electron transition character.