Characterization of the interchain selenium...selenium interaction in (TMTSF)2X by band electronic structure

Characterization of the interchain Se-Se interaction in (TMTSF)/sub 2/X requires at least two parameters, e.g., the interchain bandwidths of the two overlapping bands that arise form the two TMTSF HOMO's of each unit cell. The magnitudes of the interchain Se-Se interaction predicted from the widths of those two band exhibit the opposite trends with respect to the change in the interchain Se-Se separations. This kind of complex behavior of the interchain Se-Se interaction might be responsible for the wealth of physical phenomena observed in (TMTSF)/sub 2/X.