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<DIV><FONT face=Arial color=#000000 size=2>Dear Gromacs-users,</FONT></DIV>
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<DIV><FONT face=Arial size=2>I would like to add a new bond type to the ffbonded.itp of the Gromos53a6 force field. For that, I tried to obtain the force constant for my new bond by performing vibrational frequency calculations with Gaussian. With that, I obtained the force constant in mDyne/A.</FONT></DIV>
<DIV><FONT face=Arial size=2>My problem is now: How can I convert this value to kJ/(mol*nm(4)) as required for the force field? I already tried, but I only end up at kJ/(mol*nm(2)). Also arround the web I could only find a factor for conversion of mDyne/A to kJ/(mol*nm(2)). Is there any trick or hint you can give me about that?</FONT></DIV>
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<DIV><FONT face=Arial size=2>Thanks for your help,</FONT></DIV>
<DIV><FONT face=Arial size=2>Felix</FONT></DIV>
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