Format

Send to

Choose Destination
J Chem Phys. 2015 Apr 21;142(15):154121. doi: 10.1063/1.4917257.

Subsystem density functional theory with meta-generalized gradient approximation exchange-correlation functionals.

Author information

1
Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Grudziadzka 5, 87-100 Torun, Poland.
2
Istituto Nanoscienze-CNR, Euromediterranean Center for Nanomaterial Modelling and Technology (ECMT), Via per Arnesano 16, I-73100 Lecce, Italy.
3
Department of Physics, Temple University, Philadelphia, Pennsylvania 19122, USA.
4
Center for Biomolecular Nanotechnologies@UNILE, Istituto Italiano di Tecnologia (IIT), Via Barsanti, 73010 Arnesano, LE, Italy.

Abstract

We analyze the methodology and the performance of subsystem density functional theory (DFT) with meta-generalized gradient approximation (meta-GGA) exchange-correlation functionals for non-bonded molecular systems. Meta-GGA functionals depend on the Kohn-Sham kinetic energy density (KED), which is not known as an explicit functional of the density. Therefore, they cannot be directly applied in subsystem DFT calculations. We propose a Laplacian-level approximation to the KED which overcomes this limitation and provides a simple and accurate way to apply meta-GGA exchange-correlation functionals in subsystem DFT calculations. The so obtained density and energy errors, with respect to the corresponding supermolecular calculations, are comparable with conventional approaches, depending almost exclusively on the approximations in the non-additive kinetic embedding term. An embedding energy error decomposition explains the accuracy of our method.

PMID:
25903880
DOI:
10.1063/1.4917257
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for American Institute of Physics
Loading ...
Support Center