The atomtype opls_800 not found.

[drrahulsuresh]

Hi Users During Protein-Ligand simulation, Gromacs shows the error

[ atomtypes ] not found which i lately removed from the itp file. but even from the atoms list, gromacs shows the error, opls_800 atom type not found. Can anyone clarify the error?

[ atoms ] ; nr type resnr residue atom cgnr charge mass
1 opls_800 1 UNK C00 1 0.2180 12.0110 2 opls_801 1 UNK N01 1 -1.4490 14.0070 3 opls_802 1 UNK C02 1 0.2473 12.0110 4 opls_803 1 UNK C03 1 0.6474 12.0110 5 opls_804 1 UNK O04 1 -0.4599 15.9990 6 opls_805 1 UNK N05 1 -0.8794 14.0070 7 opls_806 1 UNK C06 1 0.3746 12.0110 8 opls_807 1 UNK N07 1 -0.4558 14.0070

Issue Information

Software name & Version : 2016.4 gromacs Method: ITP file using ligpargen

[carlosdelacruz1]

Dear drrahulsuresh, I had the same problem before. You need to include all the opls_8xx rows into your ffnonbonded file for the oplsa force field. it is because they use their own nomenclature, so you need to insert it into your forcefield to run the calculations. if you need more information don't hesitate to write me carlos.delacruz@imdea.org