Hi my ligand is Arginine (so it is not neccessary to use PRODRG )and the OPLS forcefield of gromacs make the itp file of it. I check and all the atoms present in the ligand itp file.There is no missing atom in the file.
atoms ] ; nr type resnr residue atom cgnr charge mass typeB chargeB massB 1 opls_287 1 ARG N 1 -0.3 14.0067 ; qtot -0.3 2 opls_290 1 ARG H1 1 0.33 1.008 ; qtot 0.03 3 opls_290 1 ARG H2 1 0.33 1.008 ; qtot 0.36 4 opls_290 1 ARG H3 1 0.33 1.008 ; qtot 0.69 5 opls_283 1 ARG CA 1 0.04 12.011 ; qtot 0.73 6 opls_140 1 ARG HA 1 0.06 1.008 ; qtot 0.79 7 opls_136 1 ARG CB 2 -0.12 12.011 ; qtot 0.67 8 opls_140 1 ARG HB1 2 0.06 1.008 ; qtot 0.73 9 opls_140 1 ARG HB2 2 0.06 1.008 ; qtot 0.79 10 opls_308 1 ARG CG 3 -0.05 12.011 ; qtot 0.74 11 opls_140 1 ARG HG1 3 0.06 1.008 ; qtot 0.8 12 opls_140 1 ARG HG2 3 0.06 1.008 ; qtot 0.86 13 opls_307 1 ARG CD 4 0.19 12.011 ; qtot 1.05 14 opls_140 1 ARG HD1 4 0.06 1.008 ; qtot 1.11 15 opls_140 1 ARG HD2 4 0.06 1.008 ; qtot 1.17 16 opls_303 1 ARG NE 5 -0.7 14.0067 ; qtot 0.47 17 opls_304 1 ARG HE 5 0.44 1.008 ; qtot 0.91 18 opls_302 1 ARG CZ 5 0.64 12.011 ; qtot 1.55 19 opls_300 1 ARG NH1 6 -0.8 14.0067 ; qtot 0.75 20 opls_301 1 ARG HH11 6 0.46 1.008 ; qtot 1.21 21 opls_301 1 ARG HH12 6 0.46 1.008 ; qtot 1.67 22 opls_300 1 ARG NH2 7 -0.8 14.0067 ; qtot 0.87 23 opls_301 1 ARG HH21 7 0.46 1.008 ; qtot 1.33 24 opls_301 1 ARG HH22 7 0.46 1.008 ; qtot 1.79 25 opls_271 1 ARG C 8 0.7 12.011 ; qtot 2.49 26 opls_272 1 ARG O1 8 -0.8 15.9994 ; qtot 1.69 27 opls_272 1 ARG O2 8 -0.8 15.9994 ; qtot 0.89 So for neutralizing I break 0.11 charge to 8 number of 0.01 charge and 6 number of 0.005 cherge and add them to 8+3=11 H atoms. so the total charge of my ligand is +1.Is it correct way to solve this problem in the case that I could not find any missing atom in ligand topology file? Tehran University of Medical Sciences www.tums.ac.ir -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean. _______________________________________________ gmx-users mailing list gmx-users@gromacs.org http://www.gromacs.org/mailman/listinfo/gmx-users Please search the archive at http://www.gromacs.org/search before posting! Please don't post (un)subscribe requests to the list. Use the www interface or send it to gmx-users-requ...@gromacs.org. Can't post? Read http://www.gromacs.org/mailing_lists/users.php