Hi Goette, Thanks for your mail. I have just find an article done a similar work...I am trying to reach them to get their parameters. Unfortunately I am not having Gaussian. Can you suggest me some other freely available quantum mechanics software ?
This reference article : "Binding affinity of hydroxamate inhibitors of matrix metalloproteinase-2 " Volume 10, Number 2 / April, 2004 B.Nataraj On Thu, 30 Nov 2006 14:52:18 +0100, "Maik Goette" <[EMAIL PROTECTED]> said: > Maybe, one could also think about calculating the RESP charges via QM, > e.g. with Gaussian...Further parameters, like force-constants and > dihedrals could also be evaluated... > > But what's against an expensive random number generator? > I fear I'm doing this with FEP all day long...;) > > Raja: We are (mostly) not doing LEGO here. You should inform yourself > about the theoretic parts in general. Then you would see, that LEGOing a > molecule can't be feasible....I suggest e.g. Leach, Molecular Modelling, > Section 3: Empirical force field models. > There you can find lots of information about what MD in general > resembles. > > Best regards > > Maik Goette, Dipl. Biol. > Max Planck Institute for Biophysical Chemistry > Theoretical & computational biophysics department > Am Fassberg 11 > 37077 Goettingen > Germany > Tel. : ++49 551 201 2310 > Fax : ++49 551 201 2302 > Email : mgoette[at]mpi-bpc.mpg.de > mgoette2[at]gwdg.de > WWW : http://www.mpibpc.gwdg.de/groups/grubmueller/ > > > Mark Abraham wrote: > > raja wrote: > >> Dear gmxions, > >> I am writing a topology for a ligand using AMBER99 force field > >> convention. The ligand contains the hydroxamate group, for your quick > >> reference I have drawn it below > >> O > >> HO || > >> \ / \ > >> N > > > > Your N has an unsatisfied valence... what's missing? (Don't bother to > > tell me, it doesn't matter) > > > >> Please let me know which atoms type in amber can be used for these > >> atoms.... Especially the Nitrogen atom in this group. Since I am using > >> carbonyl group and hydroxyl group atoms types for oxygen (But I am not > >> sure of its validity). Please help me to chose appropriate atoms type. > > > > Probably, none of them. Force fields are not magic numbers that can be > > applied to all possible "types" of atoms. They are constructs designed > > to be reliably applicable to fairly narrow sets of atom types under the > > range of conditions they were parametrized with (also normally narrow). > > You will see this when you read the paper that describes the development > > process of this force field. Notwithstanding, people routinely abuse > > them with gay abandon, probably on the bad advice of others, or their > > own experience of the fairly good transferability of quantum-chemical > > methods. > > > > Your only vaguely reliable course is to find a set of experimental data > > consistent with those used for the development of the force field, work > > out what new values you need to derive and to follow a process to > > optimize those values to reproduce the experimental data. This process > > is not for the inexperienced, or for the faint of heart. > > > > Otherwise, you'll have the usual expensive random number generator. > > > > Mark > > _______________________________________________ > > gmx-users mailing list gmx-users@gromacs.org > > http://www.gromacs.org/mailman/listinfo/gmx-users > > 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 > > > > . > > > _______________________________________________ > gmx-users mailing list gmx-users@gromacs.org > http://www.gromacs.org/mailman/listinfo/gmx-users > 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 -- raja [EMAIL PROTECTED] -- http://www.fastmail.fm - Same, same, but differentÂ… _______________________________________________ gmx-users mailing list gmx-users@gromacs.org http://www.gromacs.org/mailman/listinfo/gmx-users 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