Sorry for the double post, but i forgot to remove the others message. I have 
also added the average values obtained for this run 

    Statistics over 20001 steps using 4001 frames

   Energies (kJ/mol)
           Bond       G96Angle        LJ (SR)   Coulomb (SR)   Coul. recip.
    1.65683e+04    1.26644e+03   -4.02287e+05   -8.47260e+03   -4.90494e+04
      Potential    Kinetic En.   Total Energy    Temperature Pressure (bar)
   -4.41974e+05    7.91982e+04   -3.62776e+05    2.94154e+02   -1.80237e+01

          Box-X          Box-Y          Box-Z
    1.51316e+01    1.51316e+01    1.51316e+01

   Total Virial (kJ/mol)
    2.90936e+04   -4.68005e+01   -2.46005e+01
   -4.68005e+01    2.92687e+04   -2.56235e+01
   -2.46006e+01   -2.56236e+01    2.64822e+04

   Pressure (bar)
   -2.57341e+01    5.58858e-01    1.46893e-01
    5.58858e-01   -2.74443e+01    2.21040e-01
    1.46893e-01    2.21041e-01   -8.92609e-01

   Total Dipole (D)
    4.16699e+02    1.92049e+02    6.43137e+02

  Epot (kJ/mol)        Coul-SR          LJ-SR
        AOT-AOT    5.26697e+02   -4.94208e+03
          AOT-W    0.00000e+00   -2.35002e+03
        AOT-ION   -9.54002e+03   -1.89339e+03
        AOT-OCT    0.00000e+00   -2.04448e+04
            W-W    0.00000e+00   -3.88078e+02

Stephane

------------------------------

Message: 4
Date: Thu, 25 Apr 2013 13:26:32 +0000
From: ABEL Stephane 175950 <[email protected]>
Subject: [gmx-users] RE : gmx-users Digest, Vol 108, Issue 154
To: "[email protected]" <[email protected]>
Message-ID:
        <[email protected]>
Content-Type: text/plain; charset="us-ascii"

Hello Xavier,

Thank you for your response.

>> nstlist = 10 and the rlist = 1.0
My mistake, i did not changes these values when i switched to PME,

I have rerun the simulations for 400 ps in NPT with these changes and plotted 
Epot and Temp vs Time The Epot and Temp values are not stables. The average 
Temp of the system  is better than previously but fluctuate around (294 K) 
instead of 298 K . Note i use gmx4.5.5 to do my calculations.

 I have also visualized my  system at the end of the NPT run, the  na+, water, 
surfactant, octane molecules  form a slab with void

What's wrong ?

Stephane



------------------------------

Message: 5
Date: Thu, 25 Apr 2013 13:34:21 +0200
From: XAvier Periole <[email protected]>
Subject: Re: [gmx-users] Martini with PME, temp two low
To: Discussion list for GROMACS users <[email protected]>
Message-ID: <[email protected]>
Content-Type: text/plain; charset=us-ascii


Did you visualise the system? T in function of time? Epot in function of time?

As a side note (not relevant for PME) the mix of nstlist = 10 and the rlist = 
1.0 is pretty bad! You want at least rlist=1.2 when nstlist=5 and rlist=1.4 if 
nstlist =10.

On Apr 25, 2013, at 1:10 PM, ABEL Stephane 175950 <[email protected]> wrote:

> Hello all,
>
> I am trying to test the martini force field with PME for a charged system 
> that contains na+, water, surfactant, octane molecules at 298K and P=0.1MPa. 
> My system works well, if i use the standard shift parameters (correct temp, 
> and pressure). But for for the simulation with PME , the temp of the system 
> decrease to  290 K. Below my *.mdp parameters for a NPT equil at 298K
>
>
> integrator               = md
> dt                       = 0.020
> nsteps                   = 10000 ; 200ps
> nstcomm                  = 10
> comm-grps        =
> ;refcoord_scaling         = com
>
> nstxout                  = 0
> nstvout                  = 0
> nstfout                  = 0
> nstlog                   = 1000
> nstenergy                = 100
> ;nstxtcout                = 1000
> xtc_precision            = 100
> ;xtc-grps                 =
> energygrps               = AOT W ION OCT
>
> nstlist                  = 10
> ns_type                  = grid
> pbc                      = xyz
> rlist                    = 1.
>
> ; PME parameters
> coulombtype              = PME
> rcoulomb                 = 1.2
> rvdw                     = 1.2
> fourierspacing           = 0.12
> fourier_nx               = 0
> fourier_ny               = 0
> fourier_nz               = 0
> pme_order                = 4
>
> tcoupl                   = v-rescale
> tc-grps                  = AOT_W_ION OCT
> tau_t                    = 1.0 1.0
> ref_t                    = 298 298
> Pcoupl                   = berendsen
> Pcoupltype               = isotropic
> tau_p                    = 1.0
> compressibility          = 4.5e-5
> ref_p                    = 1.0
>
> ;gen_vel                  = no
> ;gen_temp                 = 0
> ;gen_seed                 = 473529
>
>
> ; MARTINI and CONSTRAINTS
> ; for ring systems and stiff bonds constraints are defined
> ; which are best handled using Lincs.
>
> constraints              = none
> constraint_algorithm     = Lincs
> unconstrained_start      = no
> lincs_order              = 4
> lincs_warnangle          = 3
>
>
> Results obtained with W/ PME
>
>   Statistics over 10001 steps using 1001 frames
>
>   Energies (kJ/mol)
>           Bond       G96Angle        LJ (SR)   Coulomb (SR)   Coul. recip.
>    1.63789e+04    1.25195e+03   -4.02093e+05   -8.22079e+03   -4.86843e+04
>      Potential    Kinetic En.   Total Energy    Temperature Pressure (bar)
>   -4.41367e+05    7.81801e+04   -3.63187e+05    2.90373e+02   -1.76470e+01
>    T-AOT_W_ION          T-OCT
>    2.90629e+02    2.90357e+02
>
> Results W:o PME
>
>   Energies (kJ/mol)
>           Bond       G96Angle        LJ (SR)   Coulomb (SR)      Potential
>    1.60482e+04    1.24820e+03   -3.34608e+05   -7.33665e+02   -3.18046e+05
>    Kinetic En.   Total Energy    Temperature Pressure (bar)
>    8.02685e+04   -2.37777e+05    2.98129e+02   -3.07123e+01
>
>          Box-X          Box-Y          Box-Z
>    1.52926e+01    1.52926e+01    1.52926e+01
>
>
>    T-AOT_W_ION          T-OCT
>    2.98141e+02    2.98129e+02
>
>
> Did I miss something ?
>
>
> Note that for the moment i do not use the polarizable water model.
>
> Thanks for your help
>
> Stephane
>
>
>
>
> --
> gmx-users mailing list    [email protected]
> http://lists.gromacs.org/mailman/listinfo/gmx-users
> * Please search the archive at 
> http://www.gromacs.org/Support/Mailing_Lists/Search before posting!
> * Please don't post (un)subscribe requests to the list. Use the
> www interface or send it to [email protected].
> * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists

--
gmx-users mailing list    [email protected]
http://lists.gromacs.org/mailman/listinfo/gmx-users
* Please search the archive at 
http://www.gromacs.org/Support/Mailing_Lists/Search before posting!
* Please don't post (un)subscribe requests to the list. Use the
www interface or send it to [email protected].
* Can't post? Read http://www.gromacs.org/Support/Mailing_Lists

Reply via email to