Atomistic modeling of amorphous silicon carbide using a bond-order potential

Molecular dynamics simulations were performed with a Brenner-type bond-order potential to study the melting of silicon carbide (SiC), the structure of amorphous SiC produced by quenching from the melt, and the evolution of the amorphous state after isochronal annealing at elevated temperatures. The simulations reveal that SiC melts above 3700 K with an enthalpy of fusion of about 0.6 eV/atom. The density of the quenched liquid is about 2820 kg/m3, in excellent agreement with the experimental value for SiC amorphized by neutron irradiation. In addition to the loss of long-range order, the quenched liquid shows short-range disorder as measured by the C homonuclear bond ratio. Upon annealing, there is partial recovery of short-range order.