An EPR, magnetic and electrochemical study of electron exchange and intermetallic interaction through polyene bridges

Abstract

The new bipyridylpolyene bridged bimetallic complexes [{LCl(NO)Mo}₂{4,4′-NC₅H₄(CHCH)_nH₄C₅N}][L = HB(3,5-Me₂C₃HN₂)₃; n= 2, 3, 4 all trans] may be reduced in two one-electron processes, the separation between which decreases by approximately 166 mV per additional ethenyl unit, they exhibit EPR spectra (300 K) consistent with rapid (>10⁸ s^–1) electron exchange between the metal centres and magnetic measurements indicate the presence of an antiferromagnetic interaction in the compound with n= 4 with a coupling –2J estimated to be 100 cm^–1.