First-principles theoretical study of metallic states of DCNQI-(Cu,Ag,Li) systems

The detailed electronic structures of several materials of organic solids. (R(1),R(2)-DCNQI)(2)M, were studied with the first-principles method based on the local-density approximation supplemented by the generalized gradient approximation. The present calculations account well for the qualitative differences in the electronic properties produced by different metal cations (M=Li,Ag? and Cu). Unique aspects of the systems with R(1)=R(2)=I are also explained based on the present calculations. The very small hole Fermi surface observed by the de Haas-van Alphen measurement for (DMe-DCNQI)(2)Cu was well reproduced by the calculation with the observed crystal structure.