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arXiv · 2504.01684

An anisotropic functional for two-dimensional material systems

Michael Lorke
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Abstract

Density function theory is the workhorse of modern electronic structure theory. However, its accuracy in practical calculations is limited by the choice of the exchange-correlation potential. In this respect, two-dimensional materials pose a special challenge, as all these materials and their heterostructures have a crucial similarity. The underlying atomic structures are strongly spatially inhomogeneous, implying that current exchange-correlation functionals, that in almost all cases are isotropic, are ill-prepared for an accurate description. We present an anisotropic screened-exchange potential, that remedies this problem and reproduces the band-gap of 2D materials as well as the piecewise linearity of the total energy with fractional occupation number.

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Michael Lorke. 2026-09-22. An anisotropic functional for two-dimensional material systems. https://arxiv.org/abs/2504.01684

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