[gmx-users] Umbrella sampling with large pulling distance (larger than half of the box size)

[DeChang Li]

Dear all,

I want to use Umbrella sampling method to calculate the potential of
mean force. Unfortunately, the distance of my two groups is very large
(about 10nm, larger than the half of simulation box size 16nm).
Without increasing the box size (too large!!), is there any ideas to
solve this problem?

In another way, is it possible to modify the pulling code (pull.c) to
force the umbrella sampling method only calculate the distance of the
groups in the box but not the periodic image?