Non-equilibrium and equilibrium simulation

Dear all,

Could you please tell me what the difference between non-equilibrium and equilibrium MD simulation is?
Does the difference have somthing to do with NVT and NPT ensembles?

I apperciate your responses in advance,
Best regards


an equilibrium simulation is of a system in an energetic equilibrium. This can be at fixed volume or pressure (so it’s not a matter of NVT or NPT): you have to define the state.

Non-equilibrium is naturally when it’s not. This can be because you are doing work on the system (e.g. shearing it), running an equilibration step to bring your system to equilibrium, or something else.