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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    • "They all have in common that in principle they can be applied to any density functional. One subclass of these approaches are density-dependent corrections , such as the exchange-hole dipole moment (XDM) model by Becke and Johnson [36] [37] [38] [39] [40] [41], the DFT+vdW/ vdW-TS method by Tkatchenko and Scheffler [42] and the density-dependent dispersion correction (dDsC) correction by Steinmann and Corminboeuf [33]. Applications of these methods are numerous and they all showed that these models can provide results with very good accuracy.[33–47] "
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    Molecular Simulation 11/2015; DOI:10.1080/08927022.2015.1066504 · 1.13 Impact Factor
    • "In a recent study, it has shown that this election works quiet well for non-equilibrium geometries.[21] The XDM parameters were obtained from [10] [11]: a1 = 0.136 and a2 = 3.178 Å. The plane wave energy cutoff was selected to 60 Ry (checking that the total energy is converged at that value) and the reciprocal space was divided into a Monkhorst-Pack [22] grid of 2 × 2 × 2 points. "
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    High Pressure Research 01/2015; 35(1). DOI:10.1080/08957959.2014.996560 · 0.95 Impact Factor
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    • "However, since the dispersion forces are always attractive they enhance the cohesive energy of the system (liquid or solid), a densification effect which could remedy to some of the inaccuracies encountered here with the use of GGA BLYP. Several routes (empirical or semi empirical) are proposed in the literature to estimate the dispersion contribution to the interaction energy (Becke and Johnson, 2005, 2007; Grimme, 2006; Civalleri et al., 2008): they are currently under investigation. "
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