Six kinds of novel TTP derivatives including BETS skeleton (1a-1f) have bee
n prepared. The crystal structures of (1b)(SbF6)(0.36) and (1c)(Au(CN)(2))(
0.36) were determined and these donor arrangements are so-called kappa -typ
e. Temperature dependence of resistivity of (1f)(SbF6)(0.32) revealed selen
ium atom substitution may suppress a metal-insulator transition.