Development of the Bethe-Salpeter method considering second-order corrections for a GW electron-hole interaction kernel
Development of the Bethe-Salpeter method considering second-order corrections for a GW electron-hole interaction kernel
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考虑对 GW 电子空穴相互作用核进行二阶修正的 Bethe-Salpeter 方法的开发
DOI：
10.1103/physrevb.106.045113
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
and K. Ohno
中科院分区：
文献类型：
--
作者：
S. Yamada;Y. Noguchi;K. Ishii;D. Hirose;O. Sugino;and K. Ohno
我们导出了电子-空穴相互作用核中的两个二阶交换项。在传统的Bethe-Salpeter方法中，这些项的贡献被忽略了，我们在全电子混合基程序中实现了它们。为了揭示这些项的影响，我们将它们应用于Thiel基准组的28个分子，并将激发能与传统的Bethe-Salpeter方法获得的激发能进行比较。此外，利用激子波函数的激子分析方法，我们估计了电子-空穴相互作用核中各项的期望值。在跃迁的激子态，两个二级交换项的贡献约为0.1- 0.2eV，而对和里德伯跃迁的贡献较小。我们的研究结果表明，conventionalBethe-Salpeter方法的错误可能会减少考虑这些条款，但是，修正的程度是不够的低估的激发能。我们相信，我们的发现是推进传统Bethe-Salpeter方法的重要一步。
We derive two second-order exchange terms in theelectron-hole interaction kernel. The contributions of these terms have been neglected in the conventionalBethe-Salpeter method, and we implement them in an all-electron mixed basis program. To reveal the effect of these terms, we apply them to 28 molecules of Thiel's benchmark set and compare theexcitation energies with those obtained from the conventionalBethe-Salpeter method. In addition, using the exciton analysis method with exciton wave functions, we estimate the expectation values for each term in theelectron-hole interaction kernel. The contribution of the two second-order exchange terms is approximately 0.1–0.2 eV at the exciton states of thetransition; however, the contributions are smaller for theandRydberg transitions. Our findings reveal that the errors of the conventionalBethe-Salpeter method are potentially reduced by considering these terms; however, the extent of the corrections is insufficient for the underestimated excitation energies. We believe that our findings are a significant step towards advancing the conventionalBethe-Salpeter method.