当前位置: X-MOL 学术Phys. Rev. Materials › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
All-electron periodicG0W0implementation with numerical atomic orbital basis functions: Algorithm and benchmarks
Physical Review Materials ( IF 3.1 ) Pub Date : 2021-01-28 , DOI: 10.1103/physrevmaterials.5.013807
Xinguo Ren , Florian Merz , Hong Jiang , Yi Yao , Markus Rampp , Hermann Lederer , Volker Blum , Matthias Scheffler

We present an all-electron, periodic G0W0 implementation within the numerical atomic orbital (NAO) basis framework. A localized variant of the resolution-of-the-identity (RI) approximation is employed to significantly reduce the computational cost of evaluating and storing the two-electron Coulomb repulsion integrals. We demonstrate that the error arising from localized RI approximation can be reduced to an insignificant level by enhancing the set of auxiliary basis functions, used to expand the products of two single-particle NAOs. An efficient algorithm is introduced to deal with the Coulomb singularity in the Brillouin zone sampling that is suitable for the NAO framework. We perform systematic convergence tests and identify a set of computational parameters, which can serve as the default choice for most practical purposes. Benchmark calculations are carried out for a set of prototypical semiconductors and insulators, and compared to independent reference values obtained from an independent G0W0 implementation based on linearized augmented plane waves (LAPWs) plus high-energy localized orbitals (HLOs) basis set, as well as experimental results. With a moderate (FHI-aims tier 2) NAO basis set, our G0W0 calculations produce band gaps that typically lie in between the standard LAPW and the LAPW+HLO results. Complementing tier 2 with highly localized Slater-type orbitals (STOs), we find that the obtained band gaps show an overall convergence towards the LAPW+HLO results. The algorithms and techniques developed in this work pave the way for efficient implementations of correlated methods within the NAO framework.

中文翻译:

具有数字原子轨道基础函数的全电子周期G0W0实现:算法和基准

我们提出一种全电子的,周期性的 G0w ^0 在数字原子轨道(NAO)基础框架内实施。采用等位分辨率(RI)近似值的局部变量来显着降低评估和存储双电子库仑排斥积分的计算成本。我们证明,通过增强用于扩展两个单粒子NAO乘积的辅助基础函数集,可以将局部RI逼近所产生的误差降低到微不足道的水平。引入了一种有效的算法来处理适用于NAO框架的布里渊区采样中的库仑奇异性。我们执行系统的收敛性测试并确定一组计算参数,这些参数可以用作大多数实际目的的默认选择。G0w ^0 基于线性化增强平面波(LAPW)加上高能局域轨道(HLO)基础集的实现,以及实验结果。借助中等(FHI防御等级2)NAO基础设置,我们的G0w ^0 计算产生的带隙通常位于标准LAPW与 拉普+LO结果。与高度局部化的Slater型轨道(STO)互补的2,我们发现所获得的带隙显示出朝向拉普+LO结果。在这项工作中开发的算法和技术为在NAO框架内有效实施相关方法铺平了道路。
更新日期:2021-01-28
down
wechat
bug