Spectral scheme for atomic structure calculations in density functional theory

Bhowmik, Sayan; Pask, John E.; Medford, Andrew J.; Suryanarayana, Phanish

doi:10.1016/j.cpc.2024.109448

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Spectral scheme for atomic structure calculations in density functional theory

Bhowmik, Sayan·Pask, John E.·Medford, Andrew J.·Suryanarayana, Phanish

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Abstract

In this study, we present a spectral scheme for atomic structure calculations in pseudopotential Kohn-Sham density functional theory. In particular, after applying an exponential transformation of the radial coordinates, we employ global polynomial interpolation on a Chebyshev grid, with derivative operators approximated using the Chebyshev differentiation matrix, and integrations using Clenshaw-Curtis quadrature. We demonstrate the accuracy and efficiency of the scheme through spin-polarized and unpolarized calculations for representative atoms, while considering local, semilocal, and hybrid exchange-correlation functionals. In particular, we find that $\mathcal{O}$(200) grid points are sufficient to achieve an accuracy of 1 microhartree in the eigenvalues for optimized norm conserving Vanderbilt pseudopotentials spanning the periodic table from atomic number Ζ = 1 to 83.

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74 ATOMIC AND MOLECULAR PHYSICS Atomic structure Density functional theory Exchange-correlation functionals Physics - Atomic and molecular physics Pseudopotentials Spectral scheme

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Bhowmik, Sayan, Pask, John E., Medford, Andrew J., Suryanarayana, Phanish. 2024-11-26. Spectral scheme for atomic structure calculations in density functional theory. https://doi.org/10.1016/j.cpc.2024.109448

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