Tersoff potential parameters for simulating cubic boron carbonitrides

We have developed Tersoff potential parameters for boron in order to simulate cubic boron carbonitride systems by molecular dynamics. Combined with parameters for C and N available from the literature, our parameters are shown to reproduce the lattice parameters and bulk moduli of boron nitride and boron carbonitride (C_0.33(BN)_0.67) with good accuracy. By simulating several systems of formula (C_x(BN)_1-x) over a wide range of carbon contents (x = 0 to 1), we observed the same trends in the deviation from ideal mixing as found experimentally. We attribute this deviation to the relatively longer C-N bonds distributed randomly throughout the intermediate C content systems.