[gmx-users] Does Gromacs record all pairwise energies and forces?

[Mark Abraham]

Lee-Ping wrote:
> Dear community,
> 
> I'm trying to access the individual pairwise energies and forces in an
> MD simulation, but from looking at the source code, it looks like the
> individual pairwise energies and forces exist only in the inner-loops.
> I've been asking GROMACS to print the forces out to a file by modifying
> the inner-loops, but this is a serious hamper on performance.  Does
> GROMACS store this information anywhere?  Thanks in advance,

No. You might get better performance by storing your pairwise matrix and 
dumping it at the end, but this could require a lot of memory. At the 
very least, don't do I/O in the innermost loops.

Mark