[gmx-users] what is the force function for proper dihedrals

[Chris Neale]

Hello,

The manual does a good job at explaining the potential energy function 
for all types of interactions. For bonded interactions the manual also 
describes the force function for every type except dihedrals. The Allan 
and Tildesley bool also lacks this information. It's one thing to know 
that the force is the negative gradient of the potential energy, but for 
proper dihedrals it is not trivial to determine this.

If anybody knows the force function for proper dihedrals then I would 
greatly appreciate a reply.

Thanks,
Chris.