On Thu, Jan 17, 2013 at 10:59 AM, James Starlight <jmsstarli...@gmail.com> wrote: > thank you for so detailed explanation.
You're welcome. Now it's up to you to use it :) > Now it's only intresting to me > if it possible to change vdw radius (assuming it as the distance from > center of atom to it outer electronic shell)? Yes, it's possible. > E.g I want to change > such value for each node in my lattice model (e.g for CH2 united atom > that value might be > 1.5 and I want dicrease it to the 1 A ( as for > simple carbon). Might I do it via some simplest modifications in the > nonbonded.itp or should I do that by means of changes in > sigma/epsillon terms (Which I also must express from A(c6) and B(c12) > based on gromac's combination rules) ? If nonbonded.itp for your chosen force field is expressed in sigma/epsilon (I guess that this is the case because you talk about an existing value for sigma), then it's only a matter of changing the sigma parameter of that atomic species. Keep in mind that this is only a description of the change - it doesn't guarantee that the change is valid. If I'd be a reviewer I'd ask for a reason for changing one of the parameters (sigma) and keeping the other (epsilon) constant. Cheers, Bogdan -- gmx-users mailing list gmx-users@gromacs.org 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 gmx-users-requ...@gromacs.org. * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists