Hey Mayur,
Though, Steve has already replied, Let me add one more thing. I hope it make some sense.
I am not sure if you could use pcff and tersoff potential together for the same system. The pcff is going to work at units “real” while tersoff is going to work in units “metal”. So I am not sure how you are going to handle that.
I think the best bet is to use pcff forcefield for SiC also.
Regards,
Vikas