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Updated: Apr 20, 2026

Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
Pair-potential approach to accurate dispersion energies between group 12 (Zn, Cd, Hg) clusters
Richard Hatz1, Vesa Hänninen, Lauri Halonen
1Laboratory of Physical Chemistry, Department of Chemistry, University of Helsinki , P.O. Box 55 (A.I. Virtasen aukio 1), FIN-00014 Helsinki, Finland.
Abstract:
Dispersion interactions between group 12 (Zn, Cd, Hg) metal clusters are studied at the CCSD(T) level with triple-ζ basis sets. We use atomic orientation dependent C6 dispersion coefficients derived from simple model systems to calculate the intermolecular dispersion energy between larger metal clusters. By using an atomic pair-potential model, we are able to obtain highly accurate results comparable to the CCSD(T) level of theory. For all the systems studied, our method results in a robust description of the dispersion energy at long distances, and it is able to outperform the examined dispersion corrected DFT calculations.
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