Efficient single-grid and multi-grid solvers for real-space orbital-free density functional theory

Ling-Ze Bu; Wei Wang

doi:10.1016/j.cpc.2023.108778

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arXiv · 2205.02311

Efficient single-grid and multi-grid solvers for real-space orbital-free density functional theory

Ling-Ze Bu·Wei Wang

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Abstract

To improve the computational efficiencies of the real-space orbital-free density functional theory, this work develops a new single-grid solver by directly providing the closed-form solution to the inner iteration and using an improved bisection method to accelerate the line search process in the outer iteration, and extended the single-grid solver to a multi-grid solver. Numerical examples show that the proposed single-grid solver can improve the computational efficiencies by two orders of magnitude comparing with the methods in the literature and the multi-grid solver can improve the computational efficiencies even once for the cases where high-resolution electron densities are needed.

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Ling-Ze Bu, Wei Wang. 2022-05-03. Efficient single-grid and multi-grid solvers for real-space orbital-free density functional theory. https://doi.org/10.1016/j.cpc.2023.108778

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