Borlido Pedro, Marques Miguel A L, Botti Silvana
Institut für Festkörpertheorie und-optik, Friedrich-Schiller-Universität Jena and European Theoretical Spectroscopy Facility , Max-Wien-Platz 1, 07743 Jena, Germany.
Institut für Physik, Martin-Luther-Universität Halle-Wittenberg and European Theoretical Spectroscopy Facility , D-06099 Halle, Germany.
J Chem Theory Comput. 2018 Feb 13;14(2):939-947. doi: 10.1021/acs.jctc.7b00853. Epub 2018 Jan 16.
Hybrid functionals are by now the state-of-the-art for the calculation of electronic properties of solids within density functional theory. The key to their performance is how a part of Fock exchange is mixed with a semilocal exchange-correlation functional. The choice of the mixing parameter is particularly critical in nonhomogeneous systems, such as an interface between two solid phases. In this work we propose a (non) local mixing function that is a functional of the electron density through an estimator of the local dielectric function. Using this mixing function to modify the PBE0 and the HSE06 hybrid functionals, we obtain band gaps and band-edge alignments at interfaces with an accuracy that is comparable to the one of the GW approximation. However, and in contrast to GW and other recent self-consistent schemes for the mixing parameter, our approach does not require the evaluation of the dielectric function and leads to a negligible increase of the computation time with respect to standard PBE0 or HSE06 hybrid calculations.
如今，杂化泛函是密度泛函理论中计算固体电子性质的最先进方法。其性能的关键在于福克交换的一部分如何与半局域交换关联泛函混合。在非均匀系统中，例如两个固相之间的界面，混合参数的选择尤为关键。在这项工作中，我们提出了一种（非）局部混合函数，它通过局部介电函数的估计量成为电子密度的泛函。使用此混合函数修改PBE0和HSE06杂化泛函，我们在界面处获得的带隙和带边对齐精度与GW近似相当。然而，与GW和其他最近用于混合参数的自洽方案不同，我们的方法不需要评估介电函数，并且相对于标准PBE0或HSE06杂化计算，计算时间的增加可以忽略不计。
