The spectral, structural and transport properties of the pseudogap system (TaSe4)(2)I

The room temperature "metallic" properties of the quasi-one-dimensional mat erial (TaSe4)(2)I differ markedly from those expected of either a Fermi or a Luttinger Liquid, showing indications of a suppression of the density of states at the Fermi level-a pseudogap. We compute properties of the materia l using a simple model in which charge density wave fluctuations produce th e pseudogap. The temperature dependence of the optical and DC conductivitie s of (TaSe4)(2)I from this model are in good agreement with experiment. We make predictions for core hole spectra and the NMR relaxation rate. In cont rast, the predictions of a strongly correlated (Luttinger Liquid) model app ear to contradict the data. (C) 2000 Elsevier Science Ltd. All rights reser ved.