Re: question about NPT

From: oguz gurbulak (gurbulakoguz_at_yahoo.com)
Date: Thu Jan 19 2012 - 03:51:42 CST

Dear Boyang, Thanks for the reply. How can I increase the Langevin piston's mass in the configuration file ? I couldn't find any keyword in conf file to do it ?  Thanks for your help. ________________________________ From: Boyang Wang <pkuwangboyang_at_gmail.com> To: oguz gurbulak <gurbulakoguz_at_yahoo.com> Cc: namd-l_at_ks.uiuc.edu Sent: Thursday, January 19, 2012 10:16 AM Subject: Re: namd-l: question about NPT Hi Oguz, pressure fluctuates a lot in NPT ensemble, because the volume fluctuates a lot. If you would like smaller fluctuation of pressure, you can increase the Langevin piston's mass in the configuration file.  Boyang On Wed, Jan 18, 2012 at 4:06 PM, oguz gurbulak <gurbulakoguz_at_yahoo.com> wrote: Dear All, > > >I performed md simulations in NPT ensamble and  got -1000 atm pressure value for the system. My aim is to find 1 atm pressure value instead of a negative pressure value.  Isthis problem indicates that the force field I use is not appropriate for my system ? or Isthisa problemcaused bythe langevin parameters ? > > >whythe system did not reach the target pressure value? Could you please share your thoughts about this problem ? > > >Kind regards. -- Boyang Wang, Ph.D.

This archive was generated by hypermail 2.1.6 : Mon Dec 31 2012 - 23:21:08 CST