# How to calculate potential energy per atom in Tersoff potential

Hi all,

I want to calculate the grain boundary (GB) formation energy between graphene and h-BN, according to the equation Eform=(Etotal-NGEG-NBEB-NNEN)/2d, where NG, NB and NN are the total number of C, B and N atoms; and EG, EB and EN are potential energy for single C, B and N atoms (some papers mention this is chemical potential). My question is in Tersoff potential (or other many-body potential), how to calculate the potential energy of single atom (i.e. EG, EB and EN)?

Kind regards,

MC

Hi all,

I want to calculate the grain boundary (GB) formation energy between
graphene and h-BN, according to the equation
Eform=(Etotal-NGEG-NBEB-NNEN)/2d, where NG, NB and NN are the total number
of C, B and N atoms; and EG, EB and EN are potential energy for single C, B
and N atoms (some papers mention this is chemical potential). My question is

I don't know where you got this equation from, but it is not correct.
A grain boundary energy between graphene and BN should consider
energies of graphene and boron nitride, not individual C, B and N
atoms.

in Tersoff potential (or other many-body potential), how to calculate the
potential energy of single atom (i.e. EG, EB and EN)?

per-atom energy is irrelavant of the pair_style used. Please have a
look at compute pe/atom doc page. But again, you should consider
energies of graphene and BN, not C, B, and N atoms.

Ray