Subject: MOPAC-Charges: Summary

From: <[email-masked]>
Date: Fri, 12 Apr 96 10:04:10 +0200

Dear CCLers

some weeks ago I asked for the charges calculated in MOPAC:

> MOPAC calculates "NET ATOMIC CHARGES" in a really simple manner: 
> atom electron densities are calculated as a sum of the diagonal elements of 
> the density matrix, and net atomic charges are then calculated by subtracting
> this value from the core charge.
> I know, there are much better methods for charge calculation (ESP...), however,
> can anybody tell me, whether this method has a special name, or can give me a
> literature reference ?

I got several different answers, however, the MOPAC charges are of Coulson type.
Thanks to: 
Darko Babic, Dave Giesen, Bill Ross, Jimmy Stewart, Brian Teppen, Lee Wilson

Martin

*-----------------------------------------------------------------------------
*  Dr. Martin Mueller
*  Fraunhofer-Institute for Environmental Chemistry and Ecotoxicology
*  (Dep.: Environmental Information and Evaluation Systems)
*  Postfach 1260
*  D-57377 Schmallenberg
*  Germany
*  Phone : *49-2972-302 227
*  FAX   : *49-2972-302 319
*  email : [email-masked]
*-----------------------------------------------------------------------------