Charge Transfer in Donor-Acceptor Crystalline Complexes

Abstract

The pressure-induced neutral-ionic transition of TTF-DMDCNQI complex is analyzed by usinga simple dimer model with electron-intramolecular vibration coupling. The coupling is shown to be responsible for a sharp neutral-ionic phase transition and characteristic hysteresis in the degree of ionicity dependence upon pressure in this complex. Ground state charge distribution is calculated as a function of small-polaron binding energies and transfer integral between donor and acceptor sites.