RE: Positive VDW energies

From: Vermaas, Joshua (
Date: Thu Oct 25 2018 - 18:29:47 CDT

Hi Nick,

Just to expand on Giacomo's answer, this is just one of those things with a CHARMM force field. Equilibrated systems are stable because the electrostatics are negative and about an order of magnitude larger in size than the VDW term. So VDW>0 is perfectly normal.


On 2018-10-25 15:39:12-06:00 wrote:

Hi Nick, the reply to one of the messages:>
sounds like a very plausible explanation.

On Thu, Oct 25, 2018 at 4:00 PM Nick Palmer <<>> wrote:
Hello everyone,
When running simulations, is it typical to have slightly higher than positive VDW energies?
After running NAMDEnergy on my system I found that the energies pretty consistently are in the range of +5 to +40. I read some previous posts which I'll link to below, but I don't think there was a resolution to them.>>
Thank you in advance

Nicholas J. Palmer
Giacomo Fiorin
Associate Professor of Research, Temple University, Philadelphia, PA
Contractor, National Institutes of Health, Bethesda, MD>>

This archive was generated by hypermail 2.1.6 : Mon Dec 31 2018 - 23:21:27 CST