[gmx-users] switch problem

[Anton Feenstra]

Ilya Chorny wrote:

> Hello,
> 
> I am noticeing some weird behavior whith the switch coulomb type.
> 
> If I set the coulomb type to switch I get oscillations in the temperature
> and if I turn on pressure coupling it gices me warnings:
> 
> Warning: pressure scaling more than 1%, mu: 0.981653 0.981653 0.981653
> 
> I equillibrated the system for at least 100 ps at NVT before turning on
> pressure coupling. The Temp oscillations are present even after 100 ps. The
> average Temp is correct but the oscillations are way to large. If I set
> coulomptype to PME or Shift the sstem behaves just fine in all cases.
[...]
> tau_t               =  0.1 0.1
[...]
> tau_p               =  0.5

It may be that these couplings are too close, leading to oscillating
interactions between T and P coupl. BUt then, you also saw them without
P coupl?


-- 
Groetjes,

Anton
  _____________ _______________________________________________________
|             |                                                       |
|  _   _  ___,| K. Anton Feenstra                                     |
| / \ / \'| | | Dept. of Pharmacochem. - Vrije Universiteit Amsterdam |
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| \_/ \_/ | | | Tel: +31 20 44 47608 - Fax: +31 20 44 47610           |
|             | Feenstra at chem.vu.nl - www.chem.vu.nl/~feenstra/       |
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