Two-center LJ potential for Nitrogen

Did you see anywhere that lammps provides such a potential directly? And how is this different from just defining two sites?

Axel.

Let me change my question. Do you have any suggestion for a suitable
potential function for simulating N2 molecules to obtain some simple
thermodynamic properties?

Mohyeddin.

No. You will have to keep searching the published literature. Axel.