[gmx-users] microcanonical

[Mark Abraham]

karamyog singh wrote:
> my system is simple gas and is interacting under simple LJ potential. 
> isn't there a simpler way to do a simulation for a constant energy mode?

It doesn't get any more simple than "don't do anything"! In gromacs, 
something approximating NVE is the result of doing nothing. Determining 
how large any cutoffs are is the next step in the quality of the 
approximation to true NVE.

> i can remove pressure couling and temp. coupling. what kind of rigorous 
> bond constraint algos do you mean? can you throw some more light on this 
> topic?

It sounds like you don't have any bonds - if you search for NVE in the 
manual you will hit a comment in about lincs_iter that might be 
relevant, I can't comment.

Mark