论文标题
使用富含有限元的全电子DFT计算中的离子力和应力张量
Ionic forces and stress tensor in all-electron DFT calculations using enriched finite element basis
论文作者
论文摘要
富集的有限元基础（其中有限元基础具有以原子为中心的数值函数 - 最近已证明是系统收敛的全电子DFT基础计算的计算有效基础。在这项工作中，我们介绍了在富集有限元中计算全电子DFT计算的变异一致的离子力和应力张量的表达式。特别是，我们将Motamarri＆Gavini中配置力的制定（物理学生成B 2018）扩展到富集的有限元基础，并阐明了富集函数产生的其他贡献。我们通过比较各种基准系统的计算力和应力与从有限差分差异基础能量获得的计算力和应力来证明配方的准确性。此外，我们还针对分子系统和周期系统的LAPW+LO基础基准计算我们的计算。
The enriched finite element basis -- wherein the finite element basis is enriched with atom-centered numerical functions -- has recently been shown to be a computationally efficient basis for systematically convergent all-electron DFT ground-state calculations. In this work, we present the expressions to compute variationally consistent ionic forces and stress tensor for all-electron DFT calculations in the enriched finite element basis. In particular, we extend the formulation of configurational forces in Motamarri & Gavini (Phys. Rev. B 2018) to the enriched finite element basis and elucidate the additional contributions arising from the enrichment functions. We demonstrate the accuracy of the formulation by comparing the computed forces and stresses for various benchmark systems with those obtained from finite-differencing the ground-state energy. Further, we also benchmark our calculations against Gaussian basis for molecular systems and against the LAPW+lo basis for periodic systems.
