From: ABEL Stephane (
Date: Mon Aug 06 2018 - 08:21:57 CDT

Dear all,

I would like to use fftk to derive parameters for the PK11195* (N-[(2R)-butan-2-yl]-1-(2-chlorophenyl)-N-methylisoquinoline-3-carboxamide) ligand and I have two questions:

1) Since this molecule contains a chlorine atom can I use the default procedure of fftk to derive the charge and the bonded parameters ?
2) When I use fftk (v.192) to obtain the Gaussian input file and specify in the last column of the PDB the atom chemical nature "Cl" (see below), in the Gaussian input file, the chlorine atom is changed to a carbon atom and consequently GAUSSIAN stops with the following error "The combination of multiplicity 1 and 175 electrons is impossible". How to modify the file gau and/or the PDB file to avoid this error ?


** ATOM 14 Cl1 PKA H 201 7.326 4.965 2.664 1.00 0.00 Cl

Thank you