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arXiv · 0906.1283

Comparison of charged-defect finite-size supercell correction methods in a general framework

Hannu-Pekka Komsa·Tapio T. Rantala
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Abstract

Starting from the total energy expressions within density functional theory, we are able to perform a comparison of several currently used charged-defect finite-size supercell correction schemes in a unified manner. This approach also provides a framework for a further development of corrections not only for DFT supercell calculations, but also for more advanced methods and for complex geometries. The comparison is performed for three separate defect cases: a gallium vacancy in GaAs, a beryllium interstitial in GaAs and a vacancy in diamond. We found two methods working sufficiently well for all three cases: a method which is very similar to one presented by Freysoldt, and a slightly altered potential alignment method.

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Hannu-Pekka Komsa, Tapio T. Rantala. 2009-06-06. Comparison of charged-defect finite-size supercell correction methods in a general framework. https://arxiv.org/abs/0906.1283

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