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<p style="margin: 0px;">I started a small 2 nucleic acid system for FEP testing. As well as turning on fep, I set RNA_Chain_A as the couple-moltype. I also set couple-lambda0 and couple-lambda1 to vdw-q and none respectively. I then began a "steep" mdrun and got this error:</p>
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<p style="margin: 0px;">Program mdrun, VERSION 4.5<br />
Source code file: topsort.c, line: 112<br />
<br />
Fatal error:<br />
Function type Improper Dih. not implemented in ip_pert<br />
For more information and tips for troubleshooting, please check the GROMACS<br />
website at http://www.gromacs.org/Documentation/Errors</p>
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<p style="margin: 0px;">I have searched for this on google and found nothing. Do I need an Improper Dihedral section in my top/itp file? I have ran this same system with fep off and it runs perfectly.</p>
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<p style="margin: 0px;">Any help is much appreciated.</p>
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<p style="font-family: monospace; white-space: nowrap; margin: 5px 0px 5px 0px;">TJ Mustard<br />
Email: mustardt@onid.orst.edu</p>
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