<table cellspacing="0" cellpadding="0" border="0" ><tr><td valign="top" style="font: inherit;"><DIV>Dear gmx users,</DIV>
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<DIV> It seems that I have found a strange temperature value after NVT equilibrium for 200 ps. I simulate a CNT with two graphite sheets in water box. I do not want to them to deform or change their shaps, So I use a very large position restraint (1*10^6) to keep their shaps. The temperature was set to 300 K, but after NVT equilibrium, the tempertaure was 330K.</DIV>
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<DIV>.mdp content</DIV>
<DIV>define = -DPOSRES_CNTGATE -DPOSRES_K -DPOSRES_CL</DIV>
<DIV>; OPTIONS FOR WEAK COUPLING ALGORITHMS<BR>; Temperature coupling <BR>tcoupl = v-rescale<BR>nsttcouple = -1<BR>nh-chain-length = 1<BR>; Groups to couple separately<BR>tc-grps = Other Water_and_ions<BR>; Time constant (ps) and reference temperature (K)<BR>tau-t = 0.1 0.1<BR>ref-t = 300 300</DIV>
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<DIV>results</DIV>
<DIV>Energy Average Err.Est. RMSD Tot-Drift<BR>-------------------------------------------------------------------------------<BR>Temperature 331.548 2.6 10.3739 15.0042 (K)<BR>T-Other 436.927 12 39.4112 67.2519 (K)<BR>T-Water_and_ions 303.349 0.16 6.07417
1.02328 (K)</DIV>
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<DIV>the Other, that is CNT and two graphite sheets temperature is very high!!!</DIV>
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<DIV>Howerver when I freeze them, the temperture is OK</DIV>
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<DIV>freezegrps = K CL Other<BR>freezedim = Y Y Y Y Y Y Y Y Y</DIV>
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<DIV>the results is</DIV>
<DIV><BR>Energy Average Err.Est. RMSD Tot-Drift<BR>-------------------------------------------------------------------------------<BR>Temperature 299.998 0.0034 4.84173 -0.0066645 (K)<BR>T-Other 0 0 0 0 (K)<BR>T-Water_and_ions
299.998 0.0034 4.84173 -0.0066645 (K)</DIV>
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<DIV>So I should freeze them or use a small postion restraint to constaint them, in order to get the correct temperture?</DIV>
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<DIV>Zhongjin He</DIV></td></tr></table>