From owner-chemistry@ccl.net Mon Sep  4 05:58:00 2006
From: "Tanja van Mourik tanja.vanmourik() st-andrews.ac.uk" <owner-chemistry]~[server.ccl.net>
To: CCL
Subject: CCL:G: BSSE and Counterpoise method
Message-Id: <-32476-060904053148-5984-EbHVymuh/WfVbFbFLvF5IQ]~[server.ccl.net>
X-Original-From: Tanja van Mourik <tanja.vanmourik\a/st-andrews.ac.uk>
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Date: Mon, 04 Sep 2006 09:55:12 +0100
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Sent to CCL by: Tanja van Mourik [tanja.vanmourik%st-andrews.ac.uk]
Dear Fuji,

> I found the following model input for the counterpoise method in gaussian manual. In this, counterpoise=2 means this system is composed by two molecules, or HF---HF. The numbers on the right means that this atom belongs to the molecule 1 or 2.
> Now, in order to calculate BSSE, I want to specify ghost atoms (NewBq key word) for the molecule 2 . Can any one tell me how to do this? I mean I need the syntax.
> 

You do not need to specify the ghost orbitals when using the 
Counterpoise keyword; Gaussian automatically calculates the dimer, 
monomer1+ghost, monomer2+ghost, and monomer-without-ghost energies (all 
at the geometry of the dimer) - five energies in total for a 
two-fragment system.  The monomer+ghost energies are indicated by "DCBS" 
(dimer centred basis set), the monomer-without-ghost energies  by "MCBS" 
(monomer centred basis set). Gaussian uses these energies to calculate 
the CP-corrected dimer energy and BSSE energy, which are printed at the 
end of the output.

Hope that helps,

Tanja
-- 
   =================================================================
    Tanja van Mourik
    Royal Society University Research Fellow
    School of Chemistry, University of St. Andrews
    North Haugh, St. Andrews
    Fife KY16 9ST, Scotland (UK)

    email: tanja.vanmourik]|[st-andrews.ac.uk
    web:   http://chemistry.st-and.ac.uk/staffmember.php?id=tvm
   =================================================================