Li Qiang schrieb: > Dear all, Hi Qiang,
> I am simulating short peptide in GROMACS. Center of mass need to be > removed to keep the peptide from jumping out. I guess this is only a visual problem, but read page 18 in the manual. > I have two questions about this: > 1, when I remove COM of the peptide using comm_grps, do I need to put > the solvent(including the counter ion) at the same time for COM removal? In a solvent simulation I would do linear COM removal of the whole system only (as is done automatically). I guess there will be artifacts if you just remove the translation of the solute (slight collisions with the solvent on one side and underpressure on the other side). But anyone please correct me if there is a clever algorithm to prevent that! ;-) > or the program will take care of the whole system automatically? Gromacs does COM removal automatically ("linear" on a group called "rest", which means the whole system if no comm_grps is given, as written in the log file) if you don't explicitly turn it off ("none" or nstcomm=0). Merry Xmas Christian > 2, Can anybody tell how the COM removal is achieved (in gromacs or other > methods available)? > > thank you > > Qiang > > _______________________________________________ > gmx-users mailing list gmx-users@gromacs.org > http://www.gromacs.org/mailman/listinfo/gmx-users > Please search the archive at http://www.gromacs.org/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/mailing_lists/users.php > -- Dr. Christian Burisch Protein Mechanics and Evolution Group CAS-MPG Partner Institute for Computational Biology Shanghai Institutes for Biological Sciences 320 Yue Yang Road, 200031 Shanghai, P. R. China Tel: +86 21 54920478 Fax: +86 21 54920451 _______________________________________________ gmx-users mailing list gmx-users@gromacs.org http://www.gromacs.org/mailman/listinfo/gmx-users Please search the archive at http://www.gromacs.org/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/mailing_lists/users.php