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Hi,<br><br>What do you mean with effective energy?<br>The Gromacs conserved energy term?<br><br>For very small tau_t the current implementation does not work well.<br>Bussi mailed me a proper implementation that I will put in when I have time.<br><br>Berk<br><br>> From: servaas.michielssens@student.kuleuven.be<br>> To: gmx-users@gromacs.org<br>> Date: Thu, 7 May 2009 09:02:52 +0200<br>> Subject: [gmx-users] v-rescale - harmonic oscillator<br>> <br>> Hi,<br>> <br>> I did some experiments with a harmonic oscillator (diatomic molecule<br>> without charge en LJ parameters) using the v-rescale thermostat. First I<br>> ran a simulation in the NVE ensemble with a time-step of 0.0001ps, total<br>> energy was constant here. <br>> <br>> Then I tried simulating the system with the v-rescale thermostat, same<br>> time-step of 0.0001ps and tau_t=100,10,1,0.1,0.01,0.001. For none of<br>> those simulations the effective energy was conserved. <br>> (effective energy should be a conserved quantity for NVT simulations<br>> with v-rescale thermostat, JOURNAL OF CHEMICAL PHYSICS Volume: 126<br>> Issue: 1 Article Number: 014101 Published: JAN 7 2007 )<br>> <br>> So what is going wrong here? Would one expect this thermostat to fail<br>> for such system (e.g. a simple Nose-Hoover is known to fail for the<br>> harmonic oscillator)? <br>> <br>> <br>> Thanks in advance,<br>> <br>> Servaas<br>> <br>> _______________________________________________<br>> gmx-users mailing list gmx-users@gromacs.org<br>> http://www.gromacs.org/mailman/listinfo/gmx-users<br>> Please search the archive at http://www.gromacs.org/search before posting!<br>> Please don't post (un)subscribe requests to the list. Use the <br>> www interface or send it to gmx-users-request@gromacs.org.<br>> Can't post? Read http://www.gromacs.org/mailing_lists/users.php<br><br /><hr />See all the ways you can stay connected <a href='http://www.microsoft.com/windows/windowslive/default.aspx' target='_new'>to friends and family</a></body>
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