Changes of physical properties of anion radical salts having low melting points in the TCNQ system

The anion radical salts in the TCNQ system with 1-ethy1-3-methylimidazolium (EMI) and l-butyl-3-methylimidazolium (BMI) were prepared The 1:1 salts of EMI-TCNQ (1) and BMI-TCNQ (3) melted at 145 and 155 °C, respectively, and were stable even in the liquid state. The conductivity of 1 increased by four orders of magnitude at melting owing to the carrier generation by the dissociation of TCNQ dimers and decreased by three orders of magnitude at freezing.