CCL: partial charge fitting - free QM package



 Sent to CCL by: Mark Thompson [mark.|.arguslab.com]
 
I am constructing drug molecules to dock into a receptor using molecular mechanics forcefield representation of atoms. The drug molecules were built in Sybyl and partial charges were first added using the Gasteiger-Marsili charges by default. I then performed an AM1 MOPAC calculation to derive Mulliken charges which were differed to some extent. I do not currently have a program to perform higher level ab initio calculations from which tto derive better charges.
 
Where may I obtain a free QM program that performs ab initio calculations with acceptable basis sets for small organic molecules from which to derive MM partial charges?
 
GAMESS is a good program. It's free. (http://www.msg.ameslab.gov/GAMESS/GAMESS.html)
 Mark
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 Mark Thompson
 mark|arguslab.com
 http://www.arguslab.com
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