Nuclear cusps and singularities in the nonadditive kinetic potential bifunctional from analytical inversion

Article Article scientifique Article Nuclear cusps and singularities in the nonadditive kinetic potential bifunctional from analytical inversion eng 2022-10-17 2022-10-17 author Banafsheh Mojdeh 0000-0003-2573-1160 657588 author Wesolowski Tomasz Adam 0000-0001-5792-4616 92358 Département de chimie physique (CHIFI) author Gould Tim 0000-0002-7191-9124 author Kronik Leeor 0000-0001-6791-8658 author Strubbe David A. 0000-0003-2426-5532 1-12 042812 10.1103/PhysRevA.106.042812 2469-9926 https://link.aps.org/doi/10.1103/PhysRevA.106.042812 The nonadditive kinetic potential 𝑣NAD is a key quantity in density-functional theory (DFT) embedding methods, such as frozen density embedding theory and partition DFT. 𝑣NAD is a bifunctional of electron densities 𝜌B and 𝜌tot=𝜌A+𝜌B. It can be evaluated using approximate kinetic-energy functionals, but accurate approximations are challenging. The behavior of 𝑣NAD in the vicinity of the nuclei has long been questioned, and singularities were seen in some approximate calculations. In this article, the existence of singularities in 𝑣NAD is analyzed analytically for various choices of 𝜌B and 𝜌tot, using the nuclear cusp conditions for the density and Kohn-Sham potential. It is shown that no singularities arise from smoothly partitioned ground-state Kohn-Sham densities. We confirm this result by numerical calculations on diatomic test systems HeHe, HeLi+, and H2, using analytical inversion to obtain a numerically exact 𝑣NAD for the local density approximation. We examine features of 𝑣NAD which can be used for development and testing of approximations to 𝑣NAD⁡[𝜌B,𝜌tot] and kinetic-energy functionals. Density functional theory Electronic structure of atoms & molecules Atomic, molecular & optical Condensed matter, materials & applied physics Dewey 540 Australian Research Council (ARC) Discovery Projects - Grant ID: DP200100033 DP200100033 AU Discovery Projects Australian Research Council (ARC) ARC Future Fellowships - Grant ID: FT210100663 FT210100663 AU ARC Future Fellowships 38 Département de chimie physique 142 false Physical review, A 106 4 dcfe22aa-a993-42f7-bf0c-c87477cb32f3 Article (Published version) Restricted Article_scientifique_from_crossref.pdf 2932260 application/pdf 0b716724c12331771a7d1d3bcacb885043e8ec3de35c3da9e27a1ee82b8df2eb restrictedAccess Faculté des sciences / Section de chimie et biochimie / Département de chimie physique

Title	Published in	Year	Views	Downloads

Nuclear cusps and singularities in the nonadditive kinetic potential bifunctional from analytical inversion	Physical review, A	2022	23	0
Nonadditive kinetic potentials from inverted Kohn-Sham problem	International Journal of Quantum Chemistry	2018	257	1

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Banafsheh, Mojdeh