  Thermodynamic and electronic properties are obtained for a lattice-gas model
fluid with self-consistent, partial, occupation of its sites; the self
consistency consists in obtaining ionic configurations from grand-canonical
Monte Carlo simulations based on fits to the exact, electronic, tight-binding
energies of isothermal ensembles of those same ionic configurations. The energy
of an ion is found to be a concave-up function of its local coordination.
Liquid-vapor coexistence densities and the electrical conductivity, which shows
a metal-nonmetal transition, have been obtained.
