Exact kinetic energy enables accurate evaluation of weak interactions by the FDE-vdW method

Journal Article · Fri Aug 28 04:00:00 EDT 2015 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.4928531· OSTI ID:22493568

Sinha, Debalina; Pavanello, Michele ^[1]

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1. Department of Chemistry, Rutgers University, Newark, New Jersey 07102 (United States)

The correlation energy of interaction is an elusive and sought-after interaction between molecular systems. By partitioning the response function of the system into subsystem contributions, the Frozen Density Embedding (FDE)-vdW method provides a computationally amenable nonlocal correlation functional based on the adiabatic connection fluctuation dissipation theorem applied to subsystem density functional theory. In reproducing potential energy surfaces of weakly interacting dimers, we show that FDE-vdW, either employing semilocal or exact nonadditive kinetic energy functionals, is in quantitative agreement with high-accuracy coupled cluster calculations (overall mean unsigned error of 0.5 kcal/mol). When employing the exact kinetic energy (which we term the Kohn-Sham (KS)-vdW method), the binding energies are generally closer to the benchmark, and the energy surfaces are also smoother.

• OSTI ID: 22493568
• Journal Information: Journal of Chemical Physics, Journal Name: Journal of Chemical Physics Journal Issue: 8 Vol. 143; ISSN JCPSA6; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ACCURACY
BENCHMARKS
BINDING ENERGY
DENSITY
DENSITY FUNCTIONAL METHOD
DIMERS
ELECTRON CORRELATION
EVALUATION
FLUCTUATIONS
FUNCTIONALS
KINETIC ENERGY
POTENTIAL ENERGY
RESPONSE FUNCTIONS
SURFACES