[gmx-users] Pressure calculated from g_energy showing negative value

[Anton Feenstra]

Sunita Patel wrote:

> Dear gmx-users,
> 
> In the .mdp file I have included following parameters for pressure
> coupling.
> 
> pcoupl                            = berendsen
> tau_p                             = 0.5
> compressibility                   = 4.5e-5
> ref_p                             = 1.0
> 
>>From g_energy calculation I got negative value of pressure with large
> fluctuation. What could be the  reason for this ?

Microscopic pressures fluctuate a lot. This is normal behavior, as long
as the average is correct (which it appears to be in your case).



-- 
Groetjes,

Anton
  _____________ _______________________________________________________
|             |                                                       |
|  _   _  ___,| K. Anton Feenstra                                     |
| / \ / \'| | | Dept. of Pharmacochem. - Vrije Universiteit Amsterdam |
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