Charge ordering due to π–d coupling in one-dimensional system

Abstract We investigate the one-dimensional extended Hubbard model at quarter filling coupled to antiferromagnetically ordered Ising spins to elucidate the interplay between π correlated electrons and d localized spins in π – d systems. Temperature dependence of charge and spin correlations are calculated by quantum Monte Carlo simulations. The results show that the coupling to the Ising spins remarkably enhances charge-order correlation in the presence of the intersite Coulomb repulsion and furthermore induces ferromagnetic correlation. We also discuss our results in connection with recent experiments on the Fe-phthalocyanine compound TPP [ Fe ( Pc ) ( CN ) 2 ] 2 .