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Date: Mon, 12 Jul 1999 10:51:42 +0200
From: "Ed E. Moret" <E.E.Moret-!at!-pharm.uu.nl>
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To: chemistry -A_T- ccl.net
Subject: Mopac93/COSMO DOES like my Zwitter ion
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Hi CCL

The definitive answer to my question regarding Mopac93 and Zwitter ions
is:

Zwitter ions are unstable in vacuum. Use Cosmo (keyword eps=78.4) to
simulate solvation or add solvent/counterions.

After recompiling in order to enable Cosmo, the new screening worked
wonders.

Even some experimental evidence is given in
J. Am. Chem. Soc. 1998 120 5098

Thank you very much Thomas Wyttenbach
and many thanks as well to

John M. McKelvey
Hajime Takashima
Andrey Bliznyuk
Antonio Morreale
Ansgar Schuffenhauer
William A. Wylie
Jose I. Garcia

With best regards
Ed Moret
-- 
| Ed E. Moret	(&$at$&more&$at$&)	Department of Medicinal Chemistry
| Faculty of Pharmacy	Utrecht University	The Netherlands
| Tel.: +31 30 2536979(2536958)	Fax: +31 30 2536655 
| E-mail: E.E.Moret /at\pharm.uu.nl	WWW: http://wwwcmc.pharm.uu.nl/moret/