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<DIV><FONT face=ΣΧΤ² color=#008000>Thanks Mark.</FONT></DIV>
<DIV><FONT face=ΣΧΤ² color=#008000>But when one polymer chain was used, non-bonded
interaction has already been there. Because one chain means
C44H156O22.</FONT></DIV>
<DIV><FONT face=ΣΧΤ² color=#008000>After all, I'd like to try more
chains.</FONT></DIV>
<DIV><FONT face=ΣΧΤ² color=#008000></FONT> </DIV>
<DIV>Message: 1<BR>Date: Tue, 06 Mar 2007 17:01:52 +1100<BR>From: Mark Abraham
<<A
href="mailto:Mark.Abraham@anu.edu.au">Mark.Abraham@anu.edu.au</A>><BR>Subject:
Re: [gmx-users] vacuum right but melt collapse<BR>To: Discussion list for
GROMACS users <<A
href="mailto:gmx-users@gromacs.org">gmx-users@gromacs.org</A>><BR>Message-ID:
<<A
href="mailto:45ED03D0.6010803@anu.edu.au">45ED03D0.6010803@anu.edu.au</A>><BR>Content-Type:
text/plain; charset=GB2312<BR><BR>kitty ji wrote:<BR>> Hi GMX user:<BR>>
<BR>> A model for Poly(vinyl methyl ether) was built with OPLS force field (
<BR>> all H ).<BR>> <BR>> <BR>> <BR>> When the model was
run alone (a single chain) in vacuum, anything goes ok.<BR>> <BR>>
<BR>> <BR>> But with 45 chains box, the system will be collapse with a
little bond <BR>> elongates abnormal whatever in NVT or NPT.<BR>>
<BR>> <BR>> <BR>> The relax time of pressure and temperature were
adjust but no helpful.<BR>> <BR>> <BR>> <BR>> How can I found
some possible reason and then fix it ? Any advise will <BR>> be
appreciated.<BR><BR>If an isolated molecule doesn't do anything strange, and two
more more<BR>do, then you have a problem with inter-molecular interactions, i.e.
the<BR>non-bonded ones. Try with just 2 chains to verify this... and
look<BR>carefully at the atom types and the non-bonded parameters for
them.<BR><BR>Mark<BR><BR></DIV>
<DIV><FONT face=ΣΧΤ² color=#008000></FONT> </DIV>
<DIV><FONT face=ΣΧΤ²
color=#008000>*************************************************<BR>Ji
Qing<BR>Institute of Chemistry, Chinese Academy of Sciences<BR>Tel:
0086-10-62562894
£¬82618423<BR>*************************************************</FONT></DIV></BODY></HTML>