Chemical control of the monovalent-divalent electron-transfer phase transition in biferrocenium-TCNQ salts

摘要

An ionic molecular crystal of (1'1'''-dineopentylbiferrocene)(F_1TCNQ)_3 exhibits a first-order phase transition from a monovalent state (D~+A_3~-) to a divalent state (D~(2+)A_3~(2-)) at around 120 K. The transition was successfully controlled by modulation of the redox potentials using F_nTCNQ (n = 0-2) and by chemical-pressure effects.