Charge gap and interchain correlation in quasi-one-dimensional dimerized organic conductors

We study the relation between the charge gap and the interchain one-body co rrelation function in quasi-one-dimensional dimerized organic conductors at quarter filling, by applying the density matrix renormalization group meth od to a three-chain extended Hubbard model. The charge gap increases with t he degree of dimerization in the intrachain hopping integrals. When the cha rge gap is larger than the interchain hopping integral, the interchain hopp ing correlation is strongly suppressed, as observed in the (TMTTF)(2)X salt s.