β_co‐(ET)₂I₃: Non‐electrochemical synthesis and structural and physical properties of an organic superconductor with 7.1 K ≤ <i>T</i>_c ≤ 7.9 K

Abstract

Synthesis of the superconducting radical cation salt β co ‐(ET) 2 I 3 obtained by the direct oxidation of either hydrogenated or deuterated bis(ethylenedithio)tetrathiafulvalene (ET) with a stoichiometric amount of iodine is reported. The structure and physical properties of the resulting compounds are presented and compared with those of other (ET) 2 I 3 phase. β co ‐(ET) 2 I 3 is found to have very similar superconducting properties to those of α t ‐(ET) 2 I 3 and the question is raised as to whether they are actually distinct phases.