<html><head></head><body><div style="font-family: Verdana;font-size: 12.0px;"><div>I appologise, I meant defined at the same time without complaining, not just either direction.
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<div style="margin:0 0 10px 0;"><b>Gesendet:</b> Montag, 29. April 2013 um 22:23 Uhr<br/>
<b>Von:</b> "lloyd riggs" <lloyd.riggs@gmx.ch><br/>
<b>An:</b> "S. Watkins" <gmx-users@gromacs.org><br/>
<b>Betreff:</b> Aw: [gmx-users] Re: how is the pulling force measured</div>
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<div style="margin: 10.0px 5.0px 5.0px 10.0px;padding: 10.0px 0 10.0px 10.0px;border-left: 2.0px solid rgb(195,217,229);"><b>Dear All,</b></div>
<div style="margin: 10.0px 5.0px 5.0px 10.0px;padding: 10.0px 0 10.0px 10.0px;border-left: 2.0px solid rgb(195,217,229);"><b>Doing a water/temp energy minimization just for a figure with a large molecule that has several connected parts, I ran into a bizzar question.</b></div>
<div style="margin: 10.0px 5.0px 5.0px 10.0px;padding: 10.0px 0 10.0px 10.0px;border-left: 2.0px solid rgb(195,217,229);"><b>So I found its possible by accident to define improper dihedrails forwards and backwards without gromacs complaining, such as atom 1 2 3 4 and 4 3 2 1. My question is, if your topology has this, does it affect the calculations (angle energy or other)?</b></div>
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<div style="margin: 10.0px 5.0px 5.0px 10.0px;padding: 10.0px 0 10.0px 10.0px;border-left: 2.0px solid rgb(195,217,229);"><b>Stephan Watkins</b></div>
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