Two new cation radical bis(ethylenedithio)tetraselenafulvalene (BETS) salts, α-(BETS)6Bi3Cl12·PhCl and (BETS)2Bi2Cl8: synthesis, structure and conducting properties. First characterisation of the new trinuclear anion [Bi3Cl12]3–

Abstract

Two new radical cation salts, (BETS)₆Bi₃Cl₁₂·PhCl 1 and (BETS)₂Bi₂Cl₈ 2, where BETS is bis(ethylenedithio)tetraselenafulvalene, have been obtained and their structures and conducting properties studied. Salt 1 has a layered structure, consisting of radical cation layers of the α type, and segregated anion sheets containing discrete [Bi₃Cl₁₂]^3– trinuclear anions and PhCl solvent molecules. It is metallic down to 180 K. The crystal structure of salt 2 consists of stacks of BETS radical cations, with polymeric [(Bi₂Cl₈)_n]^2n– anion chains arranged in a chessboard fashion. The compound 2 exhibits semiconducting properties.