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arXiv · 2609.04517

Calculation of DFT Spin-Orbit Spillage with Quantum ESPRESSO

Duy Quan Nguyen·Paul C. H. Li
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Abstract

This work describes the calculation of spin-orbit spillage from a crystal structure. Spin-orbit spillage provides a measure of the likelihood that a material has topological character. The spillage also provides the reference quantity for the machine-learning classifier of Choudhary et al., which predicts whether the spillage exceeds a specified threshold rather than the calculation of its numerical value directly. The complete computation workflow was applied to the insulating compound BaMg2Bi2, yielding a spillage of 2.094 compared with the published VASP spillage of 2.075, corresponding to a difference of 0.9%. The calculation is described in terms of two Quantum ESPRESSO (QE) calculations of spillage performed with and without spin-orbit coupling, the role of relativistic pseudopotentials, and the subsequent wavefunction-overlap analysis. The limitations of the same calculation procedure for semimetals are also examined.

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Duy Quan Nguyen, Paul C. H. Li. 2026-09-03. Calculation of DFT Spin-Orbit Spillage with Quantum ESPRESSO. https://arxiv.org/abs/2609.04517

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