From: Francesco Pietra (
Date: Tue Apr 14 2020 - 14:48:26 CDT

I forgot to mention that I had loaded to VMD
CGenFF: Topology for the Charmm General Force Field v. 3.1 *
* for Small Molecule Drug Design

---------- Forwarded message ---------
From: Francesco Pietra <>
Date: Tue, Apr 14, 2020 at 7:57 PM
Subject: ATOM LPH
To: VMD Mailing List <>

Parameterizing a small organic molecule bearing a iodine atom with
CHARMM General Force Field (CGenFF) program version 2.2.0, the line

ATOM LP1 LPH 0.050 ! on I

was written in the topology, at the end of the list of atoms.
Autopsf with VMD 1.9.4a38 for that molecule as a ligand of nucleosides,
crashed with error "unknown atom type LPH"

Commenting out that line, psf/pdb were generated.

Is that what is now expected?

thanks for advice

francesco pietra