Electronic band structure study of A(2)Mo(9)S(11) (A=K, Rb) and K1.8Mo9S11

The electronic band structures of A(2)Mo(9)S(11) (A = K, Rb) and K1.8Mo9S11 are examined by extended Huckel tight binding calculations. K2Mo9S11 and K 1.8Mo9S11 are metallic and exhibit resistivity anomalies below similar to 1 15 and similar to 80 K, respectively. The origin of these anomalies is expl ained in terms of their Fermi surfaces. Our study indicates that the resist ivity anomalies of these compounds are caused by the partial nesting of the ir two-dimensional Fermi surfaces and that both K2Mo9S11 and Rb2Mo9S11 shou ld exhibit a charge density wave phenomenon. (C) 2000 Academic Press.