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On 27/02/2012 6:35 PM, zhongjin wrote:
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cite="mid:1330328146.45546.YahooMailClassic@web15604.mail.cnb.yahoo.com"
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<div>Dear GMX users,</div>
<div> </div>
<div> I find that tau_p value is very important to NTP
simulation, when I use tau_p = 1ps, the default value,
the box change a lot, only when I use tau_p = 10 ps, it
is OK.</div>
<div> </div>
<div>; Pressure coupling <br>
Pcoupl = Parrinello-Rahman<br>
Pcoupltype = semiisotropic<br>
nstpcouple = -1<br>
; Time constant (ps), compressibility (1/bar) and
reference P (bar)<br>
tau-p = 10<br>
compressibility = 0 4.5e-5<br>
ref-p = 1.0 1.0<br>
; Scaling of reference coordinates, No, All or COM<br>
refcoord_scaling = No<br>
; Random seed for Andersen thermostat<br>
andersen_seed = 815131</div>
<div> </div>
<div>So How to set up tau_p value, is 10 ps acceptable? My
system cotain a CNT membrance in it.</div>
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<br>
Such values during equilibration are often different for those for
production runs. You should not be using P-R during equilibration,
as you will see in the relevant manual section.<br>
<br>
Mark<br>
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