Low temperature metallic conductivity in bis(tetrathiotetracene) triiodide,a new organic metal

The d.c. electrical conductivity of bis(tetrathiotetracene)triiodide,a new organic metal, has been measured for 3.3K?T?300K. The room temperature conductivity is ～ 1000 Ω^-1 cm^-1. The conductivity exhibits a broad maximum of about 3000 Ω^-1 cm^-1 in the temperature range 40–80 K followed by a gradual decrease in conductivity with decreasing temperature. No sharp metal-insulator transition is observed down to 3.3 K. The conductivity at 4 K is ～ 100 Ω^-1 cm^-1.