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arXiv · 1601.06767

Towards Fully Converged GW Calculations for Large Systems

Weiwei Gao·Weiyi Xia·Xiang Gao·Peihong Zhang
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Abstract

Although the GW approximation is recognized as one of the most accurate theories for predicting materials excited states properties, scaling up conventional GW calculations for large systems remains a major challenge. We present a powerful and simple-to-implement method that can drastically accelerate fully converged GW calculations for large systems. We demonstrate the performance of this new method by calculating the quasiparticle band gap of MgO supercells. A speed-up factor of nearly two orders of magnitude is achieved for a system contaning 256 atoms (1024 velence electrons) with a negligibly small numerical error of $\pm 0.03$ eV.

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Weiwei Gao, Weiyi Xia, Xiang Gao, Peihong Zhang. 2016-01-25. Towards Fully Converged GW Calculations for Large Systems. https://doi.org/10.1038/srep36849

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