Automated selection of the local potential for transferable pseudopotentials

Casey O. Barkan; Andrew M. Rappe

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arXiv · 1811.00959

Automated selection of the local potential for transferable pseudopotentials

Casey O. Barkan·Andrew M. Rappe

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Abstract

We develop an automated procedure to select the local potential of a separable pseudopotential that minimizes transferability errors for the isolated atom, and we show that this optimization leads to significant improvements in the accuracy of predicted solid-state properties. We present pseudopotentials for Y, In, and Sn. For these pseudopotentials, our method reduces solid-state errors by 88% on average, as measured by the $\Delta$-factor test. These pseudopotentials are constructed in the Kleinman-Bylander form; however, our method is applicable to all separable pseudopotentials, such as ONCV pseudopotentials. We perform plane-wave convergence tests according to SSSP standards and show that the modifications to the local potential leave plane-wave convergence unchanged.

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Casey O. Barkan, Andrew M. Rappe. 2018-11-02. Automated selection of the local potential for transferable pseudopotentials. https://arxiv.org/abs/1811.00959

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