[gmx-users] angular momentum.

[Erik Lindahl]

K.A. Feenstra wrote:
> Nguyen Hoang Phuong wrote:
> 
>>Dear All,
>>
>>the simulations of a peptide in vacuum are performed using NVE
>>ensemble. In principal, the angular momentum of the molecule should be
>>conserved but in my simulations, its magnitude  increases as a function of
>>time. Does anyone know why?
> 
> 
> Yes, it is caused by a build-up of integration and/or round-off
> errors, which unfortunately is inevitable in a computersimulation.
> Try David's suggestion...
> 

Actually, it's probably due to your neighborlist not being longer than 
the cutoff; I'm adding some code to improve this for 3.1.5 (or 3.2, we
might have changed enough things to bump the release).

Cheers,

Erik