L. Emmert, Wonsook Choi, J. A. Marshall
Dec 2, 2003
Citations
1
Influential Citations
44
Citations
Journal
Journal of Physical Chemistry A
Abstract
[Pt((nBu)3P)2(ethynylbenzene)2] and [Pt((nBu)3P)2(1,4-diethynylbenzene)2], which possess D2h micro-symmetry in their ground states, were studied at 77 K by time-resolved infrared (TRIR), FTIR, steady-state emission, and time-resolved photoluminescence spectroscopies. The primary luminescence peaks are at 22 573 cm-1 and 20 408 cm-1, respectively, with additional resolved structure from both phenyl ring and ethynyl vibrations. A quantum chemical modeling study showed that the HOMO is composed of conjugated π-obitials, which include contribution from the dxy orbital on the platinum metal, while the LUMO consists of only the ligand π* antibonding orbitals, thus the excitation is a mixture of ππ* and MLCT. From the results of the TRIR study and from group theoretical requirements, it has been concluded that the excitation in the lowest triplet manifold is confined to one ligand, resulting in a reduction of symmetry to C2v. For the ethynylbenzene compound, the lowest energy grow-in in the TRIR spectrum is in t...