Dear All, I have been trying to determine why I am experiencing problems when I run a gromacs file through x2top. I have checked my gromacs file with VMD to ensure that the file is correct and VMD validates that my file is correct as I see the intended structure. Thus, the atoms are indeed located within reasonable distance from each other such that x2top should be recognizing the bonds.
Here is an extract from my gromacs file: 2Grph C 1 0.000 0.000 0.000 0.0000 0.0000 0.0000 2Grph C 2 0.071 -0.123 0.000 0.0000 0.0000 0.0000 2Grph C 3 0.071 0.123 0.000 0.0000 0.0000 0.0000 2Grph C 4 -0.142 0.000 0.000 0.0000 0.0000 0.0000 2Grph C 5 -0.000 -0.250 0.000 0.0000 0.0000 0.0000 2Grph C 6 0.210 -0.120 0.000 0.0000 0.0000 0.0000 I thought that in order to make x2top work correctly that I would have to modify the files as described in Christopher Stiles website (http://cs86.com/CNSE/SWNT.htm). I made the specified changes to the following files and saved them in my working directory: ffencadv.n2t ffgmx.n2t ffgmxbon.itp I also changed the name of ffgmxbon.itp to ffencadvbon.itp as I read in one post that this file should be renamed as such. After all these changes, I still experience a problem when I run the command: x2top -ff select -f graphene_nm.gro -o graphene_nm.top selecting option 7: Encad all-atom force field, using scaled-down vacuum charges When I run the above command, I receive output telling me that the atoms have 0 bonds. An extract of the output appears below for your reference. Can not find forcefield for atom H-266 with 0 bonds Can not find forcefield for atom H-267 with 0 bonds Can not find forcefield for atom H-268 with 0 bonds Can not find forcefield for atom H-269 with 0 bonds Can not find forcefield for atom H-270 with 0 bonds ------------------------------------------------------- Program x2top, VERSION 3.3.3 Source code file: x2top.c, line: 206 Fatal error: Could only find a forcefield type for 0 out of 270 atoms ------------------------------------------------------- Could you please help me resolve this issue? Thank you in advance for your assistance. Darrell Koskinen _______________________________________________ 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