[gmx-users] COM Pulling

2010-10-08 Thread Ariel Alvarez
Hi, I've been working a time ago with Pull code in Gromacs 3.3.1, calculating the components of the applied force from pull.pdo file. Now, using 4.0.5 version and re-starting with COM Pulling, as well as the great optimization, I've found that the outputs show something like the modulus o

Re: [gmx-users] Job crash: checkpoint file

2010-10-08 Thread Justin A. Lemkul
Jianhui Tian wrote: Dear GMX users, I am running a replica simulation and the job crashed with the following message: File input/output error: Cannot rename checkpoint file; maybe you are out of quota? From the mailling list, I see this might be a permission problem. However, I checked t

[gmx-users] Job crash: checkpoint file

2010-10-08 Thread Jianhui Tian
Dear GMX users, I am running a replica simulation and the job crashed with the following message: File input/output error: Cannot rename checkpoint file; maybe you are out of quota? >From the mailling list, I see this might be a permission problem. However, I checked the file permission and noth

Re: [gmx-users] Re: forces from trajectory

2010-10-08 Thread Mark Abraham
I'd take a look at do_md in src/kernel/md.c and see for myself :-) I think the question is moot, because I have the off-hand impression that, for the md integrator, constraints are not implemented through modifying the force vectors, but rather imposed by the constraint algorithm upon the post-

Re: [gmx-users] Installation failed

2010-10-08 Thread Justin A. Lemkul
Kamalesh Roy wrote: Hi.. every body I am trying to install Gromacs 4.5.1 using updated version of fftw-3.3.1 in single precision in Fedora 9... Giving an error "fftw3f library not found..." I am mentioning the path before installing but still giving that error Please copy and paste yo

[gmx-users] Re: forces from trajectory

2010-10-08 Thread Sikandar Mashayak
Could anyone please clarify on my previous question? I am very confused about the force value issue. thanks sikandar On Thu, Oct 7, 2010 at 2:27 PM, Sikandar Mashayak wrote: > Hi > > In the post-processing ( analysis) code using gromacs trajectory, I access > force values on atom using fr.x[indx_

[gmx-users] Installation failed

2010-10-08 Thread Kamalesh Roy
Hi.. every body I am trying to install Gromacs 4.5.1 using updated version of fftw-3.3.1 in single precision in Fedora 9... Giving an error "fftw3f library not found..." I am mentioning the path before installing but still giving that error Will it be successful in Red Hat enterprize edition.

[gmx-users] questions about some mdp options in 4.5.1

2010-10-08 Thread Michael Brunsteiner
Hi, just tried to start my first MD with gmx 4.5, and have a couple of questions regarding some mdp options: for the impatient ones, the short versions: 1) what is the parameter "nstcalcenergy" ? (doesn't seem to be documented) also, in the mailing list there's a discussion about a bug w

Re: [gmx-users] Self Diffusion contant

2010-10-08 Thread Javier Cerezo
This is the normal behaviour for a MSD vs. time plot. Actually, as set by default in g_msd, neither the first seconds nor the last ones are taking into consideration to calculate the difussion constant. The explanation for the non-liear curves might be the following. On one hand, at the begini

Re: [gmx-users] Charmm27 parameterization problems in GMX 4.5.1

2010-10-08 Thread Roland Schulz
Hi, one possible reason could be that the files are not included correctly. Check the -pp output. Otherwise it is difficult to tell without the files. Roland On Fri, Oct 8, 2010 at 5:48 AM, Christian Seifert < cseif...@bph.ruhr-uni-bochum.de> wrote: > Hi GMXers, > > this is a Mail from one of m

Re: [gmx-users] OPLS-AA force field

2010-10-08 Thread Jochen Hub
Hi, see here for a start: http://www.gromacs.org/Documentation/How-tos/Parameterization Cheers, Jochen On 10/8/10 Oct 8,3:51 PM, lammps lammps wrote: > > Hi everybody, > > I want to use OPLS-AA force field to do simulation for dendrimer(see > the attached files for figure and .pdb). If the

[gmx-users] OPLS-AA force field

2010-10-08 Thread lammps lammps
Hi everybody, I want to use OPLS-AA force field to do simulation for dendrimer(see the attached files for figure and .pdb). If the pH<4.0,the tertiary amines on the dendrimer will be protonated, i.e. (CH2)3-N will be changed to (CH2)3-NH+. Now, I have two questions as follows. 1. How can I use p

Re: [gmx-users] Split pmf

2010-10-08 Thread Петр Попов
2010/10/4 Jochen Hub > On 10/2/10 Oct 2,10:51 PM, Петр Попов wrote: > >> Hello, dears gmx-users! >> >> I posted a message, but didn't get a response, it was my first one, so may >> be I did something wrong. Anyway, here it is: >> >> I've already run md and got pmf and it's correct. But I want to

Re: [gmx-users] free energy calculation problem

2010-10-08 Thread Justin A. Lemkul
Павел Кудрявцев wrote: Hi, I wanna perform free energy calculation by changing parameters of amino acid residue. Since my case is rathe complicated first I tried to perform a very simplified task - to change only charges of atoms. So I peeked out one residue, keeped all its atom types and mass

[gmx-users] Charmm27 parameterization problems in GMX 4.5.1

2010-10-08 Thread Christian Seifert
Hi GMXers, this is a Mail from one of my colleagues (who is not yet member of this ) Hi GMXers, a colleague of mine (who is not yet member of our enlightened list, but maybe I can convince him, if we find a solution.. ^^) has a problem after he had copied functioning CHARMM parameters to GMX. I

[gmx-users] Simulations on GPU

2010-10-08 Thread Igor Leontyev
Finally, I compiled and ran simulations with gpu version of gromacs-4.5.1. There were several issues: 1) Precompiled OpenMM2.0 libraries and headers must be downloaded (which requires registration on their web page) and installed, otherwise cmake doesn't find some source files. 2) cmake sh

[gmx-users] free energy calculation problem

2010-10-08 Thread Павел Кудрявцев
Hi, I wanna perform free energy calculation by changing parameters of amino acid residue. Since my case is rathe complicated first I tried to perform a very simplified task - to change only charges of atoms. So I peeked out one residue, keeped all its atom types and masses and changed charges of N

RE: [gmx-users] Problem with PME + test particle insertion

2010-10-08 Thread Berk Hess
Hi, Have you checked that your numbers are converged? Such differences can easily occur when you don't sample enough. You will have to try very many orientations before you hit the right one which satisfies all hydrogen bonds. I tested PME a long time ago. Then it worked correctly. But it could

[gmx-users] Problem with PME + test particle insertion

2010-10-08 Thread Kevin Daly
Hello Gromacs users, Recently I ran some test particle insertion simulations of TIP4P/2005 water to measure the chemical potential at 470 K and 0.861 g/cc. I found that the chemical potential was 20%-25% higher than literature values. I believe there may be a problem related to using PME with te