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arXiv · 1712.02996

Compression of Wannier functions into Gaussian-type orbitals

Bakhta Athmane·Cancès Eric·Cazeaux Paul·Fang Shiang·Kaxiras Efthimios
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Abstract

We propose a greedy algorithm for the compression of Wannier functions into Gaussian-polynomials orbitals. The so-obtained compressed Wannier functions can be stored in a very compact form, and can be used to efficiently parameterize effective tight-binding Hamiltonians for multilayer 2D materials for instance. The compression method preserves the symmetries (if any) of the original Wannier function. We provide algorithmic details, and illustrate the performance of our implementation on several examples, including graphene, hexagonal boron-nitride, single-layer FeSe, and bulk silicon in the diamond cubic structure.

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Bakhta Athmane, Cancès Eric, Cazeaux Paul, Fang Shiang, Kaxiras Efthimios. 2017-12-08. Compression of Wannier functions into Gaussian-type orbitals. https://arxiv.org/abs/1712.02996

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