  Amorphous silicon (a-Si) models are analyzed for structural, electronic and
vibrational characteristics. Several models of various sizes have been
computationally fabricated for this analysis. It is shown that a recently
developed structural modeling algorithm known as force-enhanced atomic
refinement (FEAR) provides results in agreement with experimental neutron and
x-ray diffraction data while producing a total energy below conventional
schemes. We also show that a large model (500 atoms) and a complete basis is
necessary to properly describe vibrational and thermal properties. We compute
the density for a-Si, and compare with experimental results.
