Generalized Wigner lattices in one dimension and some applications to tetracyanoquinodimethane (TCNQ) salts

Estimates show that both the on-site and the near-neighbor electrostatic interactions in tetracyanoquinodimethane chains may be much greater than the bandwidth. A method of determining the exact ground state when the interactions are dominant is described; the electrons are found to have a periodic arrangement which may be regarded as a generalization of the classical Wigner lattice. It is shown how the optical spectra may be interpreted in terms of such a configuration; also that such arrangements may give rise to lattice distortions manifested as satellites in the x-ray diffraction pattern.