Structures and Properties of Radical Cation Salts of Novel Tetraselenafulvalene Derivatives (BPT-TSF, EDT-PT-TSF, and BEST-TSF) with MX 4 (M = Fe, Ga, X = Cl, Br)-Type Anions

Abstract

Using three different BETS variants (BPT-TSF 2 , EDT-PT-TSF 3 , and BEST-TSF 4 ), six new radical cation salts of D 2 MX 4 -type are prepared. The κ-type salts with FeCl 4 − anion obtained from the donors 2 and 3 are isostructural with the corresponding BETS salts. From the donor 3 , a radical salt with β-type donor packing is obtained with GaCl 4 − anion. All these salts from donors 2 and 3 are metallic down to low temperature. On the other hand, the donor 4 possessing selenium atoms in outer heterocycles gives two λ-type salts. They are highly conductive at room temperature, but not metallic at low temperature range.