FIRST-PRINCIPLES THEORETICAL-STUDY OF METALLIC STATES OF DCNQI-(CU,AG,LI) SYSTEMS

The detailed electronic structures of several materials of organic sol ids. (R(1),R(2)-DCNQI)(2)M, were studied with the first-principles met hod based on the local-density approximation supplemented by the gener alized gradient approximation. The present calculations account well f or the qualitative differences in the electronic properties produced b y different metal cations (M=Li,Ag? and Cu). Unique aspects of the sys tems with R(1)=R(2)=I are also explained based on the present calculat ions. The very small hole Fermi surface observed by the de Haas-van Al phen measurement for (DMe-DCNQI)(2)Cu was well reproduced by the calcu lation with the observed crystal structure.