About the pair style of ideal gas

hello guys, I would like to run a simulation of ideal gas for presentation of a Carnot Cycle. For an ideal gas, the potential energy is zero as there is no particle-particle interaction.Is it appropriate to set the pair style none?

Have you tried it?

I’ve tried it and the system equilibrates in the first step (macroscopic properties are unchanged), While this is in accordance with the rules, it makes me wonder about the rationale for such a setup, it seems that the system energy is entirely determined by the kinetic energy?

It is a side note, but LAMMPS may crash in case two particles occupy the exact same position in space, which can occur if there is absolutely no repulsive potential.

Please recall that it is you that is setting up this simulation and you that is providing the rationale.

LAMMPS will simply execute the force computation that you configured, the time integration that you configured and will apply Newton’s Laws of Motion and solve the resulting partial differential equations numerically based on your input. Whether that makes sense is up to you. If there are no forces the first of Newton’s Laws of Motion applies: Newton's laws of motion - Wikipedia

This should only be a problem if there is a force computation (and thus division by zero because of zero distance).

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