Theoretical investigation on the electronic structures and phosphorescent properties of seven iridium(III) complexes with the different substituted 2-phenylpyridinato ancillary ligand

The geometry structures, electronic structures, absorption, and phosphorescent properties of seven iridium(III) complexes have been investigated by using the DFT/TDDF methods. Calculations of ionization potential and electron affinity were used to evaluate the injection abilities of holes and electrons into these complexes. The lowest energy emissions of these complexes are localized at 662, 583, 502, 518, 527, 536, and 538 nm, respectively, for complexes 1-7, simulated in CH₂Cl₂ medium at M052X level. The calculated results indicate that the complex 5 possibly possesses the largest k_r value among the seven complexes.