[gmx-users] Trouble with restrained dihedrals

[Marko Petrovic]

Hello

I'm trying to run an Energy Minimisation run while restraining phi and psi of the central alanine of an alanine dipeptide in vacuum. Hopefully it won't make a difference if I run a EM equilibration or other run for this error/concept since I am trying to create a script for creating/updating the necessary files for several different simulation runs.

The error message:
ERROR 1 [file cv_restraints.itp, line 3]:
  Incorrect number of parameters - found 5, expected 3 or 6 for Dih. Rest.
  (after the function type).

The .itp file contents:
[ dihedral_restraints ]
; ai   aj   ak   al  type  label  phi  dphi  kfac  power
         5         7         9        15         1         1   -67.652   0   1   2
         7         9        15        17         1         1    59.806   0   1   2

Other possibly relevant file snippets:
.mdp file define row (1st row):
define                    = -DPOSRES_CV

topol.top ifdef statement (last in file):
#ifdef POSRES_CV
#include "cv_restraints.itp"
#endif

I hope this is the info needed to easily see what I've done wrong. (Also info on how to interpret the error message would be nice, like which 5 parameters the software found and how it coun'ts parameters so I can get them to 3 or 6 if the problem is in the .utp file)

With Regards
Marko Petrovic
Educator
Computational Science and Technology
School of Electrical Engineering and Computer Science
KTH Royal Institute of Technology