NORMAL-COORDINATE ANALYSES OF THE GROUND AND 3MLCT EXCITED-STATES OF TRIS(BIPYRIDINE)RUTHENIUM(II)

The resonance Raman and time-resolved resonance Raman (TR3) spectra of the title compound and nine of its deuteriated derivatives as well as the 15N and l5N2-3,3′-2H2 analogues are reported. These data are used to refine the previously reported ground-state force field and to derive a corresponding force field for the anion-radical fragment of the 3MLCT excited state. These force fields reproduce the observed frequencies with average errors of ∼1%. In addition, the derived fields adequately reproduce the observed shifts upon 3MLCT-state formation, in general giving shifts of appropriate sign (some shifts are to higher frequencies) and approximately correct magnitudes. Finally, the excited-state normal-mode formulations (potential energy distributions) are compared with those derived for the ground-state species, and structural implications for the 3MLCT state are discussed. © 1990 American Chemical Society.