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Published on: July 19, 2019
The origin of deficiency of the supermolecule second-order Moller-Plesset approach for evaluating interaction
Slawomir M Cybulski1, Marion L Lytle
1Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA. cybulssm@muohio.edu
Abstract:
Calculations for the complex of thymine and adenine are used to show that the supermolecule second-order Moller-Plesset perturbation theory (MP2) approach for evaluating interaction energies fails in certain cases because of the behavior of one of its components: the uncoupled Hartree-Fock dispersion energy. A simple approach for correcting the MP2 supermolecule interaction energies is proposed. It focuses on correcting a relatively small difference between the MP2 and coupled cluster interaction energies, which is a very appealing feature of the new approach considering a benchmark role played by coupled cluster results.
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