Exchange-hole dipole moment and the ospersion interaction

Department of Chemistry, Queen's University, Kingston, Ontario K7L 3N6, Canada.
The Journal of Chemical Physics (Impact Factor: 2.95). 05/2005; 122(15):154104. DOI: 10.1063/1.1884601
Source: PubMed


A simple model is presented in which the instantaneous dipole moment of the exchange hole is used to generate a dispersion interaction between nonoverlapping systems. The model is easy to implement, requiring no electron correlation (in the usual sense) or time dependence, and has been tested on various atomic and molecular pairs. The resulting C6 dispersion coefficients are remarkably accurate.

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