James J. Mayerle

Mixed-Valence in the Organic Solid State

A review of mixed valence in the organic solid state is given, with the intention of demonstrating the interplay of the various energies that stabilize the phenomenon. Since high electrical conductivity is one of the most spectacular results of mixed valence, those factors that lead to it will be discussed. Particular attention is paid to three classes of materials: the TTF halides, TTF-TCNQ and derivatives, and the newly discovered, highly conducting TTF-tetrahalo-p- benzoquinones.