[gmx-users] Exclusion and 1-4 interactions with tabulated potential

[Johannes Kamp]

Hi @ all,

I'm a little confused about 1-4 interactions at the moment and I hope 
you can help me along...

I'm using tabulated potentials for bonded and non-bonded potentials with 
the Martini FF. The 1-4 interactions are fully represented by the 
non-bonded potential, charged particles are not present. I implemented 
the non-bonded potential with -table option in mdrun. After reading 
chapter 4.6.1 and 5.7.1 of the manual about exclusion and 1-4 
interactions the following confused me:
I set the neighbor exclusion nrexcl = 3. Is that correct if I've got the 
1-4 interactions represented in my non-bonded potential, or do I have to 
set nrexcl = 2?
Furthermore in chapter 4.6.1 something is said about a reducing factor 
of two, do I have to use it? -I'm asking because in my simulations 
everything clots together, thus the nb Forces seem to be too strong.

Regards,
Johannes