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高精度的s-和t-函数用于超越RPA的方法,具有近似的交换内核

Yannick Lemke¹, Christian Ochsenfeld^1,2

¹Chair of Theoretical Chemistry, Department of Chemistry, Ludwig-Maximilians-Universität München (LMU), Butenandtstr. 5-13, D-81377 Munich, Germany.

The Journal of chemical physics

|November 15, 2023

概括

结合交换效应的新 σ 和 τ 函数为计算电子关联能量提供了更高的精度. 这些先进的函数显著优于现有方法,在化学问题解决中与顶级双混合函数竞争.

科学领域:

量子化学是一个量子化学.
计算材料科学科学计算材料科学
电子结构理论电子结构理论

背景情况:

基于直接随机相近似 (dRPA) 的 σ-函数,改善了相关性能量计算,但遭受了自我相互作用错误.
τ-functionals旨在通过包括交换内核来减轻这些错误,尽管它们已经在很大程度上接近了.

研究的目的:

导出,优化,并对包括近似交换效应在内的新 σ 和 τ 函数进行基准测试.
评估这些新型函数的性能与现有方法和最先进的双混合函数相比.

主要方法:

基于反对称的Hartree内核,二次选交换,电子孔时间依赖的Hartree-Fock (eh-TDHF/RPAx) 和近似交换内核 (AXK) 的函数的开发.
在ASCDB数据库上使用两个新的参数化 (A1,A2) 的优化.
在GMTKN55数据库上进行全面的基准测试.

主要成果:

与标准的s-functionals相比,包括交换的s-和t-functionals表现出更高的性能.
开发的功能表现出高精度,与领先的双混合功能表相竞争.
具有AXK的s-函数和具有RPAx的t-函数 (PBE0参考) 对于各种化学问题特别有效.

结论:

纳入交换效应显著提高了σ和t函数的准确性.
新的功能表现为电子相关性能量计算的有希望的进步.
这些方法为应对复杂的化学挑战提供了强大而准确的方法.

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