ELECTRONIC DENSITY-OF-STATES OF FLUID MIXTURES IN THE SINGLE SUPERCHAIN EFFECTIVE-MEDIUM APPROXIMATION

We introduce a straightforward extension to binary mixtures of Logan a nd Winn's formalism for the determination of the electronic density of states in disordered systems. Solutions obtained in the single superc hain/effective medium approximation are also presented, and though ref lecting the limitations intrinsic to the linear nature of this approxi mation, computer simulation results for the mixture of asymmetric hard spheres are reproduced quite satisfactorily. In particular the depend ence of the band shape (and the width of the band gap) on the particle size asymmetry is correctly accounted for. The implementation of effi cient integral equation algorithms to deal with complex Ornstein-Zerni ke equations also constitutes one of the key contributions of this wor k and is therefore treated in depth. (C) 1996 American Institute of Ph ysics.