A Comparison of Ground- and Excited-State properties of [Ru(bz)_2]~(2+) and bis(#eta#~6-Benzene)ruthenium(II) p-Toluenesulfonate Using the Density Functional Theory

摘要

The ground- and excited-state properties of both [Ru(bz)_2]~(2+) and crystalline bis(#eta#~6-benzene)ruthenium(II) p-toluenesulfonate are investigated using the density functional theory. A symmetry-based technique is employed to calculate the energies of the multiplet structure splitting of the singly excited triplet states. For the crystalline system, a Buckingham potential is introduced to describe the intermolecular interactions between the [Ru(bz)_2]~(2+) system and its first shell of neighbor molecules. The overall agreement between experimental and calculated ground- and excited-state properties is good, as far as the absolute transition energies, the Stokes shift, and the geometry of the excited states are concerned. The calculated d-d excitation energies of the isolated cluster are typically 1000-2000 cm~(-1) too low. An energy lowering is obtained in a_(1g) -> e_(1g)(~3E_(1g)) excited state when the geometry of [Ru(bz)_2]~(2+)is bent along the e_(1u) Renner-Teller active coordinate. It vanishes as the crystal packing is taken into account.