Subject: BSSE should not affect gradient

From: [email-masked]
Date: Thu, 12 Aug 1999 18:06:14 +0200

Dear CCL friends,
  BSSE accounts for some percents in the interaction energy
computed from MO calculation based on supermolecule
approach. There are several methods out there to correct the
BSSE. I used to have a long debate with friends that if 
I only want to use the gradient not the energy, my calculation
should not suffer from BSSE. I tried to explain to him that
the BSSE-corrected potential energy surface (PES) should
get along with the uncorrected one smoothly, if not parallely.
Yes, the depth may be different but slope should be equal.
I have made some calculations to prove my idea and I think
it works. However, he may say that this works only for some
system.
   Question is ..... does BSSE affect gradient ? Is there
any theory or paper doing on this issue ? I need only
the answer but some clever man could take this to make
a publication.
   Thanks and I hope to hear from you.
best wishes,
Teerakiat
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Teerakiat Kerdcharoen, Ph.D.

Profession:  University Lecturer
Address:     Department of Physics, Faculty of Science
             Mahidol University, Bangkok 10400  THAILAND
Office:      (66)(2)2461381      FAX (66)(2)2461381
Cellular:    (66)(1)9031130
Home:        (66)(2)5893099      FAX (66)(2)9547395
E-mail:      [email-masked], [email-masked]
WWW:         http://einstein.sc.mahidol.ac.th/simulation     
Research:    Molecular Simulation / Computational Nanotechnology
ICQ number:  Unusable now, please see again in the future .....
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