Organic conductors with three-component system containing Co, Zn, and Cd based upon BEDT-TTF

New three-component MM′(SCN)n [M′=Co, Zn, Cd, Pb] salts based upon BEDT-TTF are prepared. Especially α-ET2CsM′(SCN)4 [M′=Co, Zn] are metallic down to 20K (1bar) and under 5kbar pressure, the semiconducting behavior is observed from room temperature. The crystal structure analyses indicate that the donor arrangement is α-type and that the polymer sheet like is observed in an anion sheet. It is interesting that the organic conductor, α-ET2CsCo(SCN)4, contains the magnetic cation, Co2+.