Molecular Conductors — α–, β–, θ– and κ–ET₂I₃, Single-Component Molecular Metal and BETS Superconductors

Abstract

Since the discoveries of Peierls transitions of one-dimensional molecular metals around the early 1970s, and especially the discovery of the first organic superconductor in 1980, a great deal of progress has been made in the field of physics and chemistry of molecular conductors. In this review, our studies and the related works on the development and electromagnetic properties of several molecular conductors such as α-, β-, θ- and κ-ET₂I₃, single-component molecular metal, [Ni(tmdt)₂] and two types of magnetic organic superconductors based on BETS molecules and magnetic FeCl₄^- and FeBr₄^- anions, were briefly described. The thermal properties of magnetic organic superconductors, especially somewhat mysterious properties of the field-induced organic superconductor, λ-BETS₂FeCl₄ clarified by Nishio’s group were also described.