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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>I am interested in converting between GROMOS96 bond/angle potentials and standard<o:p></o:p></p><p class=MsoNormal>harmonic potentials. The GROMACS manual (version 4) suggests formulae for doing<o:p></o:p></p><p class=MsoNormal>so (Eq. 4.38 and Eq. 4.53). However, I am having trouble understanding where these<o:p></o:p></p><p class=MsoNormal>come from and find that they seem to give rather poor approximations for the conversions.<o:p></o:p></p><p class=MsoNormal>It seems that much more accurate (but somewhat more complex) conversion expressions <o:p></o:p></p><p class=MsoNormal>can be derived but I am wondering whether I do not fully understand the GROMOS96 bond <o:p></o:p></p><p class=MsoNormal>potentials vs. standard harmonic potentials.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Any insights? <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks, Michael.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>