Repulsive part of lennard jones potential

LAMMPS LAMMPS General Discussion
1

Hello LAMMPS users,
I am stuck with the repulsive part of lennard jones potential as for my system I want to account only the repulsive part of lennard jones potential.
In the repulsive part of the potential we have only the term: (Cij)/r^12.
Now I have the parameter (Cij) for different pairs of atoms, but which one pair style I would use? I have checked all the LAMMPS documentation, but I didn’t find out any hint. Please help me out with this problem.

You may also check the expression of the potential of my system.

expression
expression1228×527 92.8 KB

Thanks in advance

2

You will need to use this Hybrid and look here to all different styles of potentials to combine the types you need for your system.

3

Why not email the authors and ask how they did it?

4

There is no ready to use functional form for this in LAMMPS, but you can tabulate it. A little bit of googling reveals that the developers of this potential have used tables and made them available for download with instructions to use them here: CompMaterChem - Downloads

5

FWIW, I have just submitted a pull request that implements the analytical form of the Pedone (PMMCS) potential, so the parameters can be more easily used and with cutoffs beyond the tables. The tables stop before 8 Angstrom, with the analytic form it is possible to use the 15 Angstrom cutoff mentioned in the 2006 paper.

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