FEAST fundamental framework for electronic structure calculations: Reformulation and solution of the muffin-tin problem

Alan Levin; Deyin Zhang; Eric Polizzi

doi:10.1016/j.cpc.2012.06.004

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arXiv · 1106.3609

FEAST fundamental framework for electronic structure calculations: Reformulation and solution of the muffin-tin problem

Alan Levin·Deyin Zhang·Eric Polizzi

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Abstract

In a recent article [1], the FEAST algorithm has been presented as a general purpose eigenvalue solver which is ideally suited for addressing the numerical challenges in electronic structure calculations. Here, FEAST is presented beyond the "black-box" solver as a fundamental modeling framework which can naturally address the original numerical complexity of the electronic structure problem as formulated by Slater in 1937 [2]. The non-linear eigenvalue problem arising from the muffin-tin decomposition of the real-space domain is first derived and then reformulated to be solved exactly within the FEAST framework. This new framework is presented as a fundamental and practical solution for performing both accurate and scalable electronic structure calculations, bypassing the various issues of using traditional approaches such as linearization and pseudopotential techniques. A finite element implementation of this FEAST framework along with simulation results for various molecular systems are also presented and discussed.

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Alan Levin, Deyin Zhang, Eric Polizzi. 2012-05-03. FEAST fundamental framework for electronic structure calculations: Reformulation and solution of the muffin-tin problem. https://doi.org/10.1016/j.cpc.2012.06.004

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