Charge-transfer complexes of metal dithiolenes. IX. Photoinduced electron transfer within metal dithiolene-viologen ion pairs studied by flash photolysis

Abstract

Laser flash excitation of 1/1 ion pairs consisting of the reversible redox systems [M(mmt) 2 ] 2- (mnt 2- =maleonitriledithiolate) and V n+ (V=2,2'- or 4,4'-bipyridinium derivative, n=2,1) affords the electron-transfer products [M(mmt) 2 ] - and V (n-1)+ in the case of M=Pt, while no transients are observed when M=Ni. These primary redox products recombine by a fast second-order back-reaction. The cage escape efficiencies are very sensitive to the charge of the quenchers (1.0 for n=1, 0.1 for n=2)