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arXiv · 2305.09929

An unambiguous and robust formulation for Wannier localization

Kangbo Li·Hsin-Yu Ko·Robert A. DiStasio Jr.·Anil Damle
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Abstract

We provide a new variational definition for the spread of an orbital under periodic boundary conditions (PBCs) that is continuous with respect to the gauge, consistent in the thermodynamic limit, well-suited to diffuse orbitals, and systematically adaptable to schemes computing localized Wannier functions. Existing definitions do not satisfy all these desiderata, partly because they depend on an "orbital center"-an ill-defined concept under PBCs. Based on this theoretical development, we showcase a robust and efficient (10x-70x fewer iterations) localization scheme across a range of materials.

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Kangbo Li, Hsin-Yu Ko, Robert A. DiStasio Jr., Anil Damle. 2023-05-17. An unambiguous and robust formulation for Wannier localization. https://arxiv.org/abs/2305.09929

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