Re: CCL:intermolecular potential



 I've just entered this field but i would like to sugest keeping the
 geometries from the non interacting case at first due to the lower cost
 and then check what hapends when you let go. There might be a severe (?)
 softening of the interaction and a decrease in repulsive distance.
 just a thought..
 :-)
 /Harald
 On Fri, 8 May 1998, Naoko Akiya wrote:
 >
 > Hello,
 >
 > I have a very basic question -- please bear with me.  I am still trying to
 > learn the basics, and unfortunately, there is no one around me who can
 > answer this question.
 >
 > I plan to do a simulation of a solution, with one solute molecule
 > surrounded by solvent molecules.  Before I do the simulation, I need to
 > obtain parameters for the intermolecular and intramolecular potential
 > models.
 >
 > I plan to use the intramolecular potential models available in the
 > literature for both the solute and the solvent.  For the intermolecular
 > potential, I will just use the Lennard-Jones and electrostatic interaction
 > terms, but I still need to obtain the parameters.
 >
 > I would like to obtain those parameters by fitting the ab initio
 > interaction energies to this intermolecular potential.  This is where I
 > have a question (finally).  When I calculate the interaction energies by
 > ab initio methods, should I keep the geometries of the solute and the
 > solvent molecules fixed to the equilibrium geometries as specified by the
 > intramolecular potential models that I chose?  I am inclined to do so, but
 > I wanted to get the opinions of the experts...
 >
 > Thank you very much for your patience.
 >
 > =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
 >   Naoko Akiya                        nakiya "at@at" engin.umich.edu
 >   University of Michigan
 >   Dept. of Chemical Engineering      phone (734) 764-7121
 >   Ann Arbor, MI 48109-2136	     fax   (734) 763-0459
 > =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
 >
 >
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 > -- Original Sender Envelope Address: nakiya "at@at" engin.umich.edu
 > -- Original Sender From: Address: nakiya "at@at" engin.umich.edu
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 Harald Svedung (M.Sc.)			phone:		+46-31-7722816
 Department of Chemistry			fax:		+46-31-167194
 Physical Chemistry			home phone: 	+46-31-240897
 Goeteborg University			home e-mail:	harald.svedung "at@at" svedung.pp.se
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