The Peierls Transition Of Perylene Radical-Cation Salts With 2/1-Stoichiometry Containing Tetrahydrofuran

Crystal structure, microwave conductivity and static magnetic susceptibility were analyzed for the conducting perylene (PE) radical cation salts of nominal composition (PE)(2)(PF6)(1-x)(AsF6)(x) . 2/3 THF for 0 less than or equal to x less than or equal to 1. Crystallographic phase transitions in the high-temperature metal phase were also characterized by differential scanning calorimetry and election spin resonance. The Peierls transition occuring at 100-120 K (depending on x) and the opening of the energy gap in the semiconductor phase were determined from the magnetic data. The dependence of these properties on the size of the complex anions and the packing of the PE molecules is discussed.