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Updated: Jun 3, 2026
12:11
Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
Chemical accuracy for the van der Waals density functional.
Jiří Klimeš1, David R Bowler, Angelos Michaelides
1London Centre for Nanotechnology and Department of Chemistry, University College London, London WC1E 6BT, UK.
Summary
Selecting appropriate exchange functionals significantly enhances the accuracy of the non-local van der Waals density functional (vdW-DF) method. This improvement is crucial for accurately modeling dispersion and hydrogen-bonded systems, including water adsorption on salt.
Area of Science:
- Computational chemistry
- Materials science
- Quantum mechanics
Background:
- The non-local van der Waals density functional (vdW-DF) is a promising method for studying dispersion-bonded systems.
- Accurate modeling of weak interactions is essential in various chemical and material science applications.
Purpose of the Study:
- To improve the accuracy of the vdW-DF method for dispersion and hydrogen-bonded systems.
- To identify optimal exchange functionals for vdW-DF calculations.
Main Methods:
- Systematic evaluation of existing and novel exchange functionals within the vdW-DF framework.
- Benchmarking against the S22 dataset for weakly interacting dimers and water clusters.
- Assessing performance for water adsorption on salt.
Main Results:
- Judicious selection of exchange functionals dramatically improves vdW-DF accuracy for dispersion and hydrogen bonding.
- Identified functionals achieve better-than-chemical accuracy for the S22 benchmark set.
- Enhanced performance observed for water adsorption on salt.
Conclusions:
- The choice of exchange functional is critical for the performance of vdW-DF.
- Optimized vdW-DF functionals provide highly accurate results for weakly interacting systems.
- This approach offers a more reliable tool for computational studies of molecular interactions and adsorption.
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