----- Original Message ----- From: Gaurav Chopra <[email protected]> Date: Friday, March 6, 2009 19:08 Subject: [gmx-users] Change only one atom pair VdW interaction To: [email protected]
> Hello, > > I wanted to know if one can change the VdW epsilon for just one atom pair. If > suppose my system has only carbons, hydrogen and oxygen and if I just want to > change the epsilon for C-O interaction for VdW without effecting anything > else, i.e. not changing C-C interaction for the oplsaa forcefield, is there a > way to do this without modifying the code? As epsilon_H = 0, the only thing > which will be effected by changing epsilon_C would be C-O and C-C > interaction, but I do not want to change C-C interaction but only C-O > interaction. The mechanism for this stuff varies from force field to force field, but you should start with a thorough knowledge of chapter 5 - knowing how your force field is constructing and/or reading parameters from the .itp files. I think all force fields will let you simply specify non-bonded parameters in your [molecule] sections that will override the ones that would otherwise be looked up from the .itp files. Mark _______________________________________________ gmx-users mailing list [email protected] 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
