EFFECT OF CONJUGATION ON THE OSCILLATOR STRENGTH OF THE RUTHENIUM(III) CYANAMIDE CHROMOPHORE

complexes, [(NH3)(5)Ru(L)][ClO4](2), where L(-) = cyanamide, phenylcya namide, 3-cysnamidobiphenyl 1-cyanamidonaphthalene, 2-cyanamidonaphtha lene, 2-cyanamidophenanthrene, and 1-oyanamidopyrene anions, were synt hesized and characterized by cyclic voltammetry and electronic absorpt ion spectroscopy. The Ru(III/II) couple was shown to shift positively with increasing conjugation of the group attached to the cyanamide moi ety and indicated withdrawal of cyanamide electron density onto the co njugated group. Extended Hueckel calculations of the free anion ligand s permitted estimates of transition dipole moment lengths, R, fur the b(1)() <-- b(1) transition of the cyanamide complexes. Only an approx imate positive correlation was shown between oscillator strength and R (2).