Theoretical characterization of the lowest triplet excited states of the tris-(1,4,5,8-tetraazaohenanthrene) ruthenium dication complex

The ground and the lowest triplet excited states of the tris-(1,4,5,8-tetraazaphenanthrene) ruthenium complex [[Ru[(tap).sub.3]].sup.2+] are studied. The electronic structures of the metal-to-ligand charge-transfer states (MLCT) and metal-centered (MC) triplet states are discussed by using density functional theory (DFT) and the MLCT-MC equilibrium is examined.