Fe(II)-Fe(III) electronic and magnetic interaction through a thiopyridine bridge.

Abstract

Reaction of CpFe(dppe)I with dithiopyridine in methanol and in presence of NH,PF, affords the new mixed valence complex {[CpFe(dppe)](2)-mu-S-Py}(PF6)(2) (1). Observation of an intervalence electron transfer affords the Hush parameters that permit to classify this compound as a type II Robin Day complex. The electron transfer across the pyridinethiolate ligand occurs at a rate estimated to be about 10(6) seg(-1). Variable - temperature magnetic susceptibility measurements have been carried out in the range of 5-300 degrees K. Results can be interpreted as principally due to weak intermolecular antiferromagnetic interactions between Fe (II) - Fe (III) dimers in the solid state.