Institut fu ¨r Physik, Theoretische Physik III, Technische Universitat, D-09107 Chemnitz, Germany~Received 21 February 1996!The growth of a reconstructed ~100!-silicon crystal during the deposition of 4 ML of 2-eV silicon atoms isstudied with special emphasis on the structure of the grown material. Two different molecular-dynamicssimulation methods are employed: A classical scheme using the Stillinger-Weber potential, and a density-functional-based tight-binding scheme devised by Frauenheimet al. @Phys. Rev. B 52, 11 492 ~1995!#.Wemonitor the density, pair correlation, bond and dihedral angle distribution, and ring statistics. Clear differencesin the structure of the material grown by the two different simulation schemes are observed. They can be tracedback to a too large stiffness of the classical potential, which leaves the grown material in a disordered but nottruly amorphous state. @S0163-1829~96!03324-3#I. INTRODUCTION