Subject: CCL: Request for a code for Stone's distributed multipole analysis

From: [email-masked] (Raimund Jaeger)
Date: Thu, 31 Mar 94 18:24:24 -0500

Hello, 

I am working on the calculation of the rotational flexibility of polymer 
backbones. I determined several torsional potentials of the backbone - bonds
with ab initio calculations (Gaussian '92). Currently, I'm trying to describe  
the ab initio torsional potentials with van der Waals - and electrostatic
interaction, where I use the MM2 parametrization for the vdW terms and 
electrostatic point charges derived from Mulliken's population analysis or  
natural population analysis. When I tried to fit the ab initio torsional   
potentials with vdW - and electrostatic (monopole) interactions, I got the    
impression that the results could be improved, if I include higher     
multipole momenta (dipole, quadrupole, etc.) into the electrostatic      
interaction. Stone's 'distributed multipole analysis' (DMA) calculates       
the higher electrostatic multipole momenta from the charge density obtained from
ab initio calculations. Stone's DMA seems to implemented in some ab initio 
packages, but I didn't come across a code which has an interface to the
Gaussian '92 package. Therefore my questions:
 
- Does anyone has some experience with modeling non bonded interactions with 
electrostatic interactions including higher multipole momenta (derived from 
ab initio results)? 

- Does anyone know about a program which can use Gaussian '92 results as input 
for a distributed multipole analysis?

Thanks, R. Jaeger.

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R. Jaeger                                phone: (416) 978 1697
Chemistry Dept., University of Toronto   fax :  (416) 978 8775
80 St. George St.                        e-mail: [email-masked]
Toronto, Ont. M5S 1A1
Canada
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