Hi Guys I am having great difficulty generating a histogram of the correct shape from g_wham. I am running umbrella sampling on one configuration fo two molecules at a fixed distance using the following pull parameters. ( I am just running one configuration to begin with so that can make sure that the shape of my distribution is correct).
pull = umbrella pull_geometry = distance pull_dim = Y Y Y pull_start = yes pull_ngroups = 1 pull_group0 = cage_1 pull_group1 = cage_2 pull_init1 = 0 pull_rate1 = 0.0 pull_k1 = 2000 pull_nstxout = 100 pull_nstfout = 100 I have set the force constant quite high in the hope that the system will sample the equilibrium distance much more often than the distances accessible form the harmonic potential. In the plot of count vs distance I get an upside down bell curve in which there is a larger distribution at the extremeties of the curve. Does anyone know why this may be happening? If so please let me know. Am I right in assuming that the x axis in the histo.xvg file is the distance between the centres of masses of the two molecules? Cheers Gavin -- 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/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/mailing_lists/users.php