Clearly, this is not something that can be represented using pair_style sw (Stillinger-Weber), since it includes a 1/r interaction. As I mentioned already, it appears to be something that can be defined using pair_style vashishta. Obviously, I don’t have a GeSe parameter file to give you, since I asked you to contribute the one that you are going to create. I also made it clear that when it comes to doing the arithmetic manipulations, you are on your own. If this is beyond your abilities, you should shift the focus of your research to a material for which suitable potentials already exist in LAMMPS.