Coexistence of SDW and CDW in Quarter-Filled Organic Conductors

Abstract

We have performed a mean field calculation in order to determine the ground state of a modified Hubbard model of a quarter-filled one-dimensional chain. A phase diagram is obtained as the values of the elastic constant of the chain and the on-site Coulomb energy are varied. Our result supports the experimental report concerning (TMTSF) 2 PF 6 that an X-ray observation has confirmed a coexisting phase of 2 k F CDW and 2 k F SDW.