Subject: Re: CCL:BSSE

From: uccatvm <[email-masked]>
Date: Fri, 24 May 2002 12:05:53 +0100 (BST)

Hi Olegas,
  
> In the "standard" BSSE equation (for a dimer AB):
> 
> BSSE(AB) =3D E(AB)^AB - E(A)^A - E(B)^B + [E(A')^A - E(A')^AB + E(B)^B - =
> E(B)^AB]
> 
> I've got most of the parameters, but how in G98W do I calculate E(A)^AB =
> and E(B)^AB, i.e. the energy of the monomer units in terms of the dimer =
> basis set.
  
With Gaussian, the keyword Massage has to be used for counterpoise 
corrections (assuming it's the same for G98 and G98W).  Have a look at the 
Gaussian manual: http://www.gaussian.com/00000452.htm.
There is an example there as well. However, don't believe the sentence
about counterpoise being only a crude estimate, have a look at the 
following papers to learn more about BSSE and Counterpoise:

-  F.B. van Duijneveldt, J.G.C.M. van Duijneveldt-van de Rijdt, and
   J.H. van Lenthe, Chem. Rev. 94, 1873, 1994 (on counterpoise theory)

-  S. Simon, M. Duran, J.J. Dannenberg, J. Chem. Phys. 105, 1996
   (on geometry optimizations on BSSE-corrected potential energy surfaces).

-  F.B. van Duijneveldt, "Basis Superposition Error"
   in "Molecular Interactions" S. Scheiner (ed.), Wiley (1997)

-  T. van Mourik, A.K. Wilson, K.A. Peterson, D.E. Woon, T.H. Dunning, Jr.,
   Adv. Quant. Chem. 31, 105, 1999 (showing BSSE effects on interaction
   energies, distances, and frequencies).

HTH,

Tanja
-- 
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     Tanja van Mourik                                                
     Royal Society University Research Fellow
     Chemistry Department 
     University College London    phone:    +44 (0)20-7679-4663      
     20 Gordon Street             e-mail:   work: [email-masked] 
     London WC1H 0AJ, UK                    home: [email-masked]     

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