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<P><FONT SIZE=2>Fellow gmx users,<BR>
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I am trying to create a topology file for TFE using the olpsaa/l force field to simulate a peptide in a mixed solvent. I created a molecule.itp file (as it was suggested in the manual), a molecule.gro file for TFE and I was able to place the several TFE and water molecules in a box. <BR>
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When I ran grompp before equilibrating the system, the program was expecting a topology file, so I created one instead of the .itp file. After trying grompp once again, I received an error message that read:<BR>
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Program grompp, VERSION 3.3.1<BR>
Source code file: toppush.c, line: 1180<BR>
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Fatal error:<BR>
Incorrect number of parameters - found 4, expected 6 or 12.<BR>
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My topology file is attached to this message. I left the second dihedral parameters blank since there are no planar entities in TFE, and the [ pairs ] have a value of zero since the opls forcefield calculates 1-4 interactions by scaling.<BR>
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Could you suggest any changes to my topology file?<BR>
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Thank you in advance,<BR>
<BR>
Michael Owen<BR>
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