Subject: Help on force field for simplified "atoms"

From: Guosheng Wu <[email-masked]>
Date: Mon, 23 Oct 2000 17:16:15 -0500 (CDT)

Dear folks,

Does any of you have the experience on developing force field for
simplified "atoms"? 

I know there are some papers related with simplified "atom" for CH2
or CH3, but how about biger molecules? 

For example, if I want to get a simple function V(R) for the interction
between C6H6 and C6H6, I may either summarize the LJ(rij) interctions
between all of atoms(i in one molecule and j in the other one), or I can 
do ab initio calculations for different intermolecular distances(R). By
both methods I may be able to fit the results into a simple function, say
still in LJ(R) form.  However, sometimes this mayn't work, or very
time-consuming for big molecules. 

If anyone could give me some suggestions or related reference, I will be
very grateful.

Thanks a lot!

Guosheng Wu
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Guosheng Wu    
Dept. of Chem.,  Northwestern Univ.
2145 Sheridan Road, Evanston, IL, 60208-3113
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