I was performing the equilibration and minimization of ATP in namd and vmd.
This is the error message.
FATAL ERROR: UNKNOWN PARAMETER IN CHARMM PARAMETER FILE top_all27_na.rtf
LINE=** \\\\ CHARMM27 All-Hydrogen Nucleic Acid Topology File ////*
Error is showing right in the title line of the topology file. Is there any format issues ?
I have attached the topology file mentioned in the error.