Characterisation of two different mixed-valence states in a strongly interacting dimolybdenum complex

Abstract

The pyrazine-bridged bimetallic complex [{Mo(NO)[HB(dmpz)₃]Br}₂(µ-pz)] ^z [HB(dmpz)₃ = tris(3,5-dimethylpyrazolyl)borate] exists within a five-membered electron-transfer chain where z = -2, -1, 0, +1 and +2; the mixed-valence species with z = -1 is delocalised on the EPR and IR spectroscopic timescales whereas that with z = +1 is valence-trapped.

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