Effects of charge ordering in electronic subsystem of quasi-2D BEDT-TTF conductors

Abstract

The interplay of the inter-site Coulomb repulsion which induces charge ordering, and the correlated hopping of electrons, which causes peculiar dependence of energy characteristics on a doping, is studied in a model of BEDT-TTF organic conductor electronic subsystem. By applying the projection method in the Green function equation of motion approach the single-particle energy spectrum, sublattice magnetization in charge-ordered phase, and the transition temperature have been calculated. Dependence of Verwey temperature on the band filling shows that inter-site Coulomb correlation significantly influences the width of the concentration interval in which a charge order stabilizes. The correlated hopping causes the decrease of the critical value of electron concentration and increase of Verwey temperature in whole concentration interval of charge ordering stability.