A COMPARISON OF GROUND-STATE AND EXCITED-STATE PROPERTIES OF GAS-PHASE AND CRYSTALLINE RUTHENOCENE USING DENSITY-FUNCTIONAL THEORY

The ground- and excited-state properties of both gas phase and crystal line ruthenocene, Ru(cp)(2), are investigated using density functional theory. A symmetry-based technique is employed to calculate the energ ies of the multiplet splittings of the singly excited triplet states. For the crystalline system, a Buckingham potential is introduced to-de scribe the intermolecular interactions between a given Ru(cp)(2) molec ule and its first shell of neighbors. The overall agreement between ex perimental and calculated ground- and excited-state properties is very good as far as absolute transition energies, the Stokes shift and the geometry of the excited states are concerned. An additional energy lo wering in the B-3(2) component of the 5a(1)' --> 4e(1)'' excited state is obtained when-the pseudolinear geometry of Ru(cp)(2) is relaxed al ong the low-frequency bending vibration. (C) 1998 American Institute o f Physics.