Synthesis, Crystal Structure, Photophysical Properties and Theoretical Study of a New Iridium(III) Complex Containing 2-phenylbenzothiazole Ligand.

A new bis-cyclometalated iridium(III) complex [Ir(dmabt)(2)(bipy)][PF(6)] (3) (dmabt = 4-(benzo[d]thiazol-2-yl)-N,N-dimethylaniline, bipy = 2,2'-bipyridine) has been synthesized and fully characterized. The complex 3 has been determined by X-ray structure analyses which shows that the central iridium(III) ion assumes distorted octahedral geometry. The photoluminescence spectrum exhibits orange emission maximum at 612 nm with quantum yield of 17% at 298 K. The frontier molecular orbital diagrams and the spin-allowed singlet-singlet electronic transitions of 3 have been calculated with density functional theory (DFT) and time-dependent DFT (TD-DFT), and the UV-Vis spectra are discussed based on the theoretical calculations.

N,N'-[2,2'-(Phenyl-aza-nedi-yl)bis-(ethane-2,1-di-yl)]dipicolinamide.

The asymmetric unit of the title compound, C22H23N5O2, contains two independent mol-ecules with similar conformations; the terminal pyridine rings are oriented at dihedral angles of 23.99 (8) and 18.07 (8)° with respect to the central benzene ring in one mol-ecule and 28.99 (8) and 23.22 (8)° in the other. In the crystal, N-H⋯O and weak C-H⋯O hydrogen bonds link the mol-ecules into a three-dimensional supra-molecular structure. Weak inter-molecular C-H⋯π inter-actions are also observed in the crystal.