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<DIV><FONT size=2></FONT>Dear Gromacs Users,</DIV>
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<DIV> Harmonic potentials are used in Gromacs for imposing
restraints on the motion of the system.</DIV>
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<DIV> V = 1/2 * k * (x-x0)^2</DIV>
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<DIV> And the forces are : F = -k * (x-x0) . ...</DIV>
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<DIV> I want to use constant force for the restraint. </DIV>
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<DIV> Just scale the force : F = -k * (x-x0) / sqrt (
(x-x0)**2+(y-y0)**2 + (z-z0)**2 ) ...</DIV>
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<DIV> This was very simple.</DIV>
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<DIV> But I don't know where the position restraint code
is . </DIV>
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<DIV> Could you please tell me where I can start with ? </DIV>
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<DIV> Many thanks for your help !</DIV>
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<DIV>Best Wishes,</DIV>
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<DIV> </DIV>
<DIV>Yours Sincrely,</DIV>
<DIV>Chiango Ji</DIV>
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