Subject: summary: center of cavity in continuum methods!

From: Pradipta Bandyopadhyay <[email-masked]>
Date: Mon, 2 Aug 1999 14:52:14 -0500 (CDT)

hi everybody,
       I posted the following message a few days back.
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  Dear ccl-members,
     I have a question about the continuum method of solvation. Does it
 matter where I put my molecule inside the cavity? If I put the molecule
 ( dipole) in the center of the cavity and then put it away from the center,
 the dipole moment ( with respect to the origin) changes but the dipole
 moment of uncharged systems are independent of the origin. So is it really
 independent of the postion of the dipole?
             I want to know the answer for both quantum mechanical and classica\
l
treatment of the dipole(when the charge is zero). Can anyone tell me the answer
 for both quantum menchanical and classical cases? Thanks in advance.
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  rather than putting all the replies I write the answer.
     For the onsager model (or for any model, which doesn't put any charge
  on the surface) it doesn't matter where I put the solute inside the cavity
  as long as the soule is neutral. However, for more sophisticated continuum
  models like PCM, COSMO ( which  put charges or other 'objects' on the cavity
  boundary) it matters where I put the solute.
    I thank Dr. Toomas Tamm, Dr. Antonio Luiz and Dr. Chaitanya Shridhar
  for their messages.
               Pradipta

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               *   Dr. Pradipta Bandyopadhyay          *
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