Body-centered-cubic lattice model with many-body interactions representingthe melting transition in Si

A body-centered-cubic (BCC) lattice model with realistic many-body interact ions is introduced and investigated by means of the Metropolis' Monte Carlo method to describe both crystalline and molten states of Si. Under the sim plest assumption that atoms surrounded by tetrahedral first-neighbors only have an energy lower than the other atoms, a clear first-order phase transi tion including hysteresis is observed between a solid with diamond structur e and a melt. Nucleation and domain growth are dynamically observed in cert ain range of the supercooling. In order to introduce more realistic and acc urate lattice-gas models, the Tersoff potential is renormalized and the int eractions are mapped onto a BCC lattice. Then, it is found that the phase t ransition temperature and other thermodynamic properties are dramatically i mproved compared with the case using the Tersoff potential directly in the lattice model without renormalization. (C) 1999 American Institute of Physi cs. [S0021-9606(99)51318-4].