[gmx-users] TI(slow growth) in gromacs (tip4, Parrinello-Rahman barostat) instability

[Anton Feenstra]

> 
> Dear gromacs teem! 
> 
> I find a strange behavior of gromacs, when I simulate slow growth
> of some solute in a periodic box of tip4p waters.
> (Nose-Hoover thermostat, Parrinello Rahman barostat, 500000 steps
> of 2fs., ethane molecule)
> 
> The results was unstable and warning like "cell is exploding"
> appeared in a log file.

The Nose-Hoover and Parrinello Rahman 'stats can be significantly
less stable than their "Berendsen" counterparts. This probably
explains why most people use the Berendsen 'stats, even though the
resulting ensemble is thermodynamically not well-defined.


-- 
Groetjes,

Anton
 ________ ___________________________________________________________
|        | Anton Feenstra                                            |
| .      | Dept. of Pharmacochemistry - Vrije Universiteit Amsterdam |
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