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On 4/21/2011 6:54 PM, Jianguo Li wrote:
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<div>Dear all,<br>
<br>
My molecule contains -CH=CH- fragment and I am trying to
create the topology using Charmm FF. It seems that there is no
improper dihedrals for -CH=CH- fragment in Charmm FF, while
other FF (e.g., Amber or OPLS) has additional improper
dihedrals terms for that fragment. <br>
Could anybody confirm this?<br>
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<br>
That seems to be the case, but you should go and look at the primary
sources (CHARMM parameter files and literature) to see what
reasoning might exist.<br>
<br>
Mark<br>
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