Repulsive potential between virtual sites

User discussions
1

GROMACS version: 2021.4
GROMACS modification: No

Dear gmx users,

System : Protein in water

In charmm36 and amber99sb-ildn, comb-rule = 2.

When setting up a repulsive potential between virtual sites, can I apply the same conversion of Rmin (1.2 nm) to sigma (1.06908) for both force fields,? Or, any other conversions required?

Thanks for your help.

2

The Rmin to sigma coversion is general for the Lennard-Jones potential and does not depend on the force field. But there might be unit conversions that depend on the force fields you convert between.