Electronic structure of θ-type BETS salts

A new series of θ-type BETS salts have been prepared and the crystal structure analyses and the electrical resistivity measurements have been carried out. θ-BETS2MM′(SCN)4 [MM′=RbCo, RbZn, CsCo, CsZn]are isostructural to ET analogues. The metal insulator transition occurs at 25 Kfor θ-RbM′, whereas the metallic behaviors down to 2K have been observed for θ-CsM′ and θBETS 2Ag(CN)2. The phase diagram of θ-type BETS salts shows that the electronic state is scaled by electronic correlation parameter (U/W), and that the metallic state extends wider, compared with θ-ET salts.