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Title: Evaluating interaction energies of weakly bonded systems using the Buckingham-Hirshfeld method

We present the finalized Buckingham-Hirshfeld method (BHD-DFT) for the evaluation of interaction energies of non-bonded dimers with Density Functional Theory (DFT). In the method, dispersion energies are evaluated from static multipole polarizabilities, obtained on-the-fly from Coupled Perturbed Kohn-Sham calculations and partitioned into diatomic contributions using the iterative Hirshfeld partitioning method. The dispersion energy expression is distributed over four atoms and has therefore a higher delocalized character compared to the standard pairwise expressions. Additionally, full multipolar polarizability tensors are used as opposed to effective polarizabilities, allowing to retain the anisotropic character at no additional computational cost. A density dependent damping function for the BLYP, PBE, BP86, B3LYP, and PBE0 functionals has been implemented, containing two global parameters which were fitted to interaction energies and geometries of a selected number of dimers using a bi-variate RMS fit. The method is benchmarked against the S22 and S66 data sets for equilibrium geometries and the S22x5 and S66x8 data sets for interaction energies around the equilibrium geometry. Best results are achieved using the B3LYP functional with mean average deviation values of 0.30 and 0.24 kcal/mol for the S22 and S66 data sets, respectively. This situates the BHD-DFT method among the best performing dispersion inclusivemore » DFT methods. Effect of counterpoise correction on DFT energies is discussed.« less
Authors:
 [1] ;  [2] ;  [3]
  1. Fachbereich Chemie, Technische Universität Kaiserslautern, Erwin Schrödinger Straße 52, D-67663 Kaiserslautern (Germany)
  2. Department of Chemistry, University of Antwerp, Universiteitsplein 1, B2610 Antwerp (Belgium)
  3. Algemene Chemie, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels (Belgium)
Publication Date:
OSTI Identifier:
22252878
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 140; Journal Issue: 18; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ANISOTROPY; DENSITY; DENSITY FUNCTIONAL METHOD; DISPERSIONS; INTERACTIONS; ITERATIVE METHODS; POLARIZABILITY