Solid state structures and electrical properties of neutral radical crystals of dicyano(phthalocyaninato)‐cobalt(III)

Electrically conducting neutral radical crystals can be obtained by electrochemical oxidation of dicyano(phthalocyaninato)cobalt(III) anion, [Co(Pc)(CN)2]−. The electrolysis of the potassium salt in DMSO gives Co(Pc)(CN)2·2DMSO. The solvent-free crystal can be obtained by electrolysis of K[Co(Pc)(CN)2] in acetonitrile in the presence of various second components or using salts with other cations. The intermolecular π–π overlap is efficient in the solvent-containing crystal, while that in the solvent-free crystal is much less. The electrical resistivity at room temperature of the latter has been found to be 4.5 × 103 Ω cm, which is nearly three orders higher than that of Co(Pc)(CN)2·2DMSO.