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To: "        -         (052)CHEMISTRY(a)www.ccl.net" <CHEMISTRY@www.ccl.net>
Subject: MOPAC Calculation on Radicals
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Date: Mon, 1 Mar 1999 17:48:46 +0000
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Hi,

I'm interested in trying to model free radical alkene polymerisation reactions
using MOPAC (AM1, PM3).  There appear to be two possibilities for calculations
on radicals - the Dewar half-electron method (which is invoked by the keyword
DOUBLET) and UHF.   The results differ by a few kcal/mol.

Can anyone advise me which option is likely to give the best results for
reaction thermodynamics and activation energies of a radical adding to a double
bond?  I'd also be interested in any comments on bond dissciation energies
estimated by these methods.  I'll summarise any replies.

Thanks,
Steve Rogers

email: steve_rogers@ici.com