Magnetic Properties of a New Class of Highly Conductive Organic Solids

Abstract

Magnetic susceptibility measurements have been carried out on a wide variety of organic salts based on the anion radical of tetracyanoquinodimethan (TCNQ). A correlation between the magnetic and electrical properties has been observed. Salts which exhibit the higher conductivities also exhibit a temperature‐independent paramagnetic contribution to their susceptibility, but in the less conductive materials, the odd electrons associated with the TCNQ anion radicals are paired in quasimolecular states consisting of a singlet ground state and a triplet state lying slightly above the ground state. These results are interpreted as indicating that in the higher conductivity salts the odd electrons, which are presumably the charge carriers, are degenerate as in a metal.