VMD-L Mailing List

From: Allen, Caley R (caley.allen_at_chemistry.gatech.edu)
Date: Thu Jan 23 2014 - 13:37:06 CST

Greetings All,

I have obtained a pdb file from pdb.org. After generating the psf/pdb combo using psfgen (script is below), adding a solvation box and ionizing the box in VMD- I attempt to equilibrate/minimize the protein + water + ions and I quickly get the following CHARMM error: "FATAL ERROR: UNABLE TO FIND DIHEDRAL PARAMETERS FOR NH3 CT1 CT2A CT2 (ATOMS 1 5 7 10)". The first residue, which the error is referring to is GLU. I have researched on this mailing list (where I found plenty about fatal errors relating to angles) and other resources and still can not seem to correct this issue. Any advice is appreciated. If more information is required please just let me know.

Cheers,
Caley

psfgen script:

package require psfgen
topology top_all36_prot.rtf
pdbalias residue HIS HSE
pdbalias atom ILE QD1 CD
segment U {
            pdb H.pdb
            auto angles dihedrals
          }
coordpdb H.pdb U
guesscoord
writepdb H36.pdb
writepsf H36.psf

In output file:

Reason: FATAL ERROR: UNABLE TO FIND DIHEDRAL PARAMETERS FOR NH3 CT1 CT2A CT2 (ATOMS 1 5 7 10)

Charm++ fatal error:
FATAL ERROR: UNABLE TO FIND DIHEDRAL PARAMETERS FOR NH3 CT1 CT2A CT2 (ATOMS 1 5 7 10)