ZMP-SAPT: DFT-SAPT using ab initio densities
Abstract
Symmetry Adapted Perturbation Theory (SAPT) has become an important tool when predicting and analyzing intermolecular interactions. Unfortunately, Density Functional Theory (DFT)-SAPT, which uses DFT for the underlying monomers, has some arbitrariness concerning the exchange-correlation potential and the exchange-correlation kernel involved. By using ab initio Brueckner Doubles densities and constructing Kohn-Sham orbitals via the Zhao-Morrison-Parr (ZMP) method, we are able to lift the dependence of DFT-SAPT on DFT exchange-correlation potential models in first order. This way, we can compute the monomers at the coupled-cluster level of theory and utilize SAPT for the intermolecular interaction energy. The resulting ZMP-SAPT approach is tested for small dimer systems involving rare gas atoms, cations, and anions and shown to compare well with the Tang-Toennies model and coupled cluster results.
- Publication:
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Journal of Chemical Physics
- Pub Date:
- April 2019
- DOI:
- 10.1063/1.5087208
- arXiv:
- arXiv:1903.03350
- Bibcode:
- 2019JChPh.150o4101B
- Keywords:
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- Physics - Chemical Physics;
- Physics - Applied Physics;
- Physics - Atomic and Molecular Clusters;
- Physics - Computational Physics
- E-Print:
- 23 pages, 5 figures