<P> Hello, I do the energy minimization of the butylene box , but some butylene molecules are broken after that. The butylene itp file is produced by PRODRG, as follows:</P>
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<P><EM>[ moleculetype ]<BR>; Name nrexcl<BR>BUT 3</EM></P>
<P><EM>[ atoms ]<BR>; nr type resnr resid atom cgnr charge mass<BR> 1 CH3 1 BUT C9 1 0.0049 15.0350 <BR> 2 CH2 1 BUT C6 1 -0.02442 14.0270 <BR> 3 C 1 BUT C3 1 0.07957 13.0190 <BR> 4 C 1 BUT C2 1 -0.06005 14.0270 </EM></P>
<P><EM>[ bonds ]<BR>; ai aj fu c0, c1, ...<BR> 2 1 2 0.155 7150000.0 0.155 7150000.0 ; C6 C9 <BR> 2 3 2 0.153 7150000.0 0.153 7150000.0 ; C6 C3 <BR> 3 4 2 0.135 7150000.0 0.135 7150000.0 ; C3 C2 </EM></P>
<P><EM>[ pairs ]<BR>; ai aj fu c0, c1, ...<BR> 1 4 1 ; C9 C2 </EM></P>
<P><EM>[ angles ]<BR>; ai aj ak fu c0, c1, ...<BR> 1 2 3 2 112.5 520.0 112.5 520.0 ; C9 C6 C3 <BR> 2 3 4 2 125.0 610.0 125.0 610.0 ; C6 C3 C2 </EM></P>
<P><EM>[ dihedrals ]<BR>; ai aj ak al fu c0, c1, m, ...<BR> 1 2 3 4 1 0.0 1.0 6 0.0 1.0 6 ; dih C9 C6 C3 C2 </EM></P>
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<P>Can you show me why the butylene molecules would be broken?</P>
<P>Thank you very much !</P>
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