Tight binding simulation of the thermodynamic behavior of amorphous silicon

Structures of amorphous silicon have been generated by using a suitable imp lementation of the reverse Monte Carlo technique, based on the reproduction of different experimental data. The structures have been subsequently rela xed at fixed temperature and pressure via tight binding molecular dynamics. The amorphous structures have been further characterized by evaluating str uctural, dynamic and electronic structure properties, as a function of temp erature, up to and above the melting point. The model of amorphous silicon undergoes a melting transition at T-al similar or equal to 0.55T(m) (where T-m is the homogeneous melting temperature of the bulk crystal). In the tem perature range between T-al and T-m, the system exhibits thermodynamic and structural properties typical of an undercooled liquid. (C) 1999 American I nstitute of Physics. [S0021-8979(99)05624-8].