ghost particles and potential energy calculation

Hello LAMMPS users,

Please allow me to cite a passage from a paper(kinjo 1998), “Let us introduce a ghost particle which interact with real particles via the attractive part of Lennard-Jones potantial:
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We insert the ghost particle in the simulation cell and calculate its potential energy”
What I wonder is how can I insert the ghost particle and calcuate potential energy between the ghost particles and Lennarc-Jones particles by using LAMMPS.
I would really appreciate it if someone can help me to figure out the problem.

Thanks in advance.

Thanks,
Shuwen,Yang

you can use create_atoms to insert particles. and then use run 0 to compute "single point energies (and forces).
just make sure that you reserve space for an additional atom type when creating the simulation cell, so that you can define specific interactions for that particle and also easily remove it.

axel.

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You can also use the fix widom command. I assume that you would like to insert a first particle at several spatial locations in the same configuration and computer some sort of average potential energy.

Hope it helps
Evangelos

Στις Τετάρτη, 5 Αυγούστου 2020, ο χρήστης swyang0501 <dfhgfhjdfjs@…33…1193…> έγραψε:

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