On Wed, Apr 10, 2013 at 9:46 AM, 라지브간디 <[email protected]> wrote:
> Dear gmx, > > > I am getting confusion with converting the normal hormonic potential bond > ( which is used in charmm27) to Fourth power potential bond ( gromos43a1). > > > For Example. > The value of C-O force constant, bond stretch and distance are in charmm > is 518816.0, 0.123 and 0.12. Hence I used this value for converting to > gromos type by using Fourth power potential bond equation and end up with > value of 1.29189542054402. But the value of force constant in gromos for > C-O is mentioned like this > > > #define gb_4 0.1230 1.6600e+07 > ; C - O 1200 > > > Here i dont understand what i am missing here. > > > Some guidance or suggestion or really appreciated. Thanks. > > Equation 4.38 from the 4.6.1 manual yields a force constant of approximately 17146407, which is right in the ballpark of the actual Gromos96 value. You're not going to get exact agreement between force fields since they use different parameters. -Justin -- ======================================== Justin A. Lemkul, Ph.D. Research Scientist Department of Biochemistry Virginia Tech Blacksburg, VA jalemkul[at]vt.edu | (540) 231-9080http://www.bevanlab.biochem.vt.edu/Pages/Personal/justin ======================================== -- gmx-users mailing list [email protected] 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 [email protected]. * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists
