FIRST-PRINCIPLES THEORETICAL-STUDY OF METALLIC STATES OF DCNQI-(CU,AG) SYSTEMS - SIMPLICITY AND VARIETY IN COMPLEX-SYSTEMS

The electronic structures for the metallic states of the organic solids (R1, R2-DCNQI)2M with M=Cu and Ag are studied in the local density functional theory with the plane-wave pseudopotential method. The calculations account well for the variation in the electronic properties for different choices for M, R1, and R2, and the essential features of the observed Fermi surfaces of (DMe-DCNQI)2Cu with R1=R2=CH3 are well reproduced. Analyses of the electronic specific heat and the magnetic susceptibility suggest that the electron correlation and the electron-phonon interaction may be of moderate strength. © 1995 The American Physical Society.