Theoretical Studies of the Ground and Excited Electronic States in Cyclometalated Phenylpyridine Ir(III) Complexes Using Density Functional Theory

The ground state and low-lying excited electronic states in the Ir(III) complex Ir(ppy)3, and in the related complexes Ir(ppy)2(acac) and Ir(ppy)2(bza), are studied using density functional theory techniques [where ppy = 2-phenylpyridine, acac = acetoylacetonate, and bza = benzyolacetonate]. Ir complexes of ppy have been the subject of numerous photophysical absorption and luminescence experiments and have been examined as potential donors in organic light emitting diodes (OLEDs). The electronic properties of the neutral molecules, in addition to the positive and negative ions, are studied using the B3LYP functional. Optimized geometries are compared to experimentally observed structures. Excited triplet and…