Precision and efficiency in solid-state pseudopotential calculations (固态赝势计算的精度和效率)
Gianluca Prandini, Antimo Marrazzo, Ivano E. Castelli, Nicolas Mounet & Nicola Marzari
npj Computational Materials 4:72 (2018)
doi:s41524-018-0127-2
Published online:06 December 2018
Abstract| Full Text | PDF OPEN
摘要:尽管密度泛函理论取得了巨大的成功和广泛普及,但系统的求证和验证研究在量度和广度方面仍均十分有限。本研究基于几个独立的标准,提出了一个实验方案来测试可以共享的赝势库,这些标准包括:验证全电子状态方程和声子频率、带结构、内聚能和压力的平面波收敛测试。采用这些标准,本研究获得了有序赝势库(或标准固态赝势库,SSSP),瞄准高通量材料筛选(“SSSP效率”)和高精度材料建模(“SSSP精度”)。在元素固态方程的Δ-因子检验中, SSSP精度在可应用的开源赝势库中表现最好。
Abstract:Despite the enormous success and popularity of density-functional theory, systematic verification and validation studies are still limited in number and scope. Here, we propose a protocol to test publicly available pseudopotential libraries, based on several independent criteria including verification against all-electron equations of state and plane-wave convergence tests for phonon frequencies, band structure, cohesive energy and pressure. Adopting these criteria we obtain curated pseudopotential libraries (named SSSP or standard solid-state pseudopotential libraries), that we target for high-throughput materials screening (“SSSP efficiency”) and high-precision materials modelling (“SSSP precision”). This latter scores highest among open-source pseudopotential libraries available in the Δ-factor test of equations of states of elemental solids.
Editorial Summary
Density functional theory: A protocol for testing pseudopotentials (密度泛函理论:用于赝势测试的方案)
该研究使用新提出的测试方案系统地测试现有赝势,获得了有序赝势库(或标准固态赝势库,SSSP)。尽管密度泛函理论非常受欢迎,但到目前为止,很少有人关注并验证基础赝势和投影增强波近似。由于更平滑的赝势可以实现更快的计算,所以赝势性能问题也很重要。现在,来自瑞士洛桑联邦理工学院的Nicola Marzari及其同事,介绍了共享数据库的赝势测试方案,并为85种元素选择了最佳赝势。该测试方案包括验证步骤和性能评估步骤。在高通量材料搜索中于精确度和性能之间,找到正确的平衡尤为重要,但目前这样的搜索正是全球范围内付出巨大努力有待实现的目标。
Curated pseudopotential libraries obtained by systematic testing of available pseudopotentials are obtained using a newly proposed testing protocol. Density functional theory is very popular, but little attention has been devoted so far to the verification of the underlying pseudopotentials and projector augmented-wave approximations. The issue of performance is also of importance, as smoother pseudopotentials would enable faster calculations. Now, Nicola Marzari and colleagues from the Ecole Polytechnique Fédérale de Lausanne in Switzerland introduce a testing protocol for pseudopotentials in publicly available libraries, and select the optimal pseudopotential for 85 elements. The protocol includes both a verification step and performance evaluation step. Finding the right balance between precision and performance is particularly important for high-throughput materials searches, which are currently the focus of big efforts worldwide.