> 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 - =
> 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).
Tanja van Mourik
Royal Society University Research Fellow
University College London phone: +44 (0)20-7679-4663
20 Gordon Street e-mail: work: T.vanMourik "at@at" ucl.ac.uk
London WC1H 0AJ, UK home: tanja "at@at" netcomuk.co.uk