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Hi,<br><br>Sorry for not being clear on this issue.<br>I am currently following and preparing lectures and exercises for a workshop<br>and do not have time to sit back and go deeply into this issue.<br><br>What my conclusion is from looking at the code:<br>With TIP4P water and free-energy any non-perturbed atoms<br>that are in the same energy group as perturbed atoms might<br>have missing Coulomb interactions with TIP4P.<br><br>Thus the only simulations TIP4P free-energy simulations that are surely correct are:<br>Have a separate energy group that contains only perturbed particles,<br>possible combined with non-perturbed particles that have no charge.<br>Or using the environment variable GMX_NO_SOLV_OPT.<br><br>The bug actually also affects another situation:<br>TIP4P and free-energy combined with rcoulomb > rvdw could lead to missing<br>Coulomb interactions beyond rvdw between TIP4P and charges in the same<br>energy group as perturbed particles.<br>But this probably nobody has tried.<br><br>Berk<br><br><br /><hr />Express yourself instantly with MSN Messenger! <a href='http://clk.atdmt.com/AVE/go/onm00200471ave/direct/01/' target='_new'>MSN Messenger</a></body>
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