Chair of Theoretical Chemistry, Department of Chemistry, University of Munich (LMU), D-81377 Munich, Germany.
Max Planck Institute for Solid State Research, D-70569 Stuttgart, Germany.
J Chem Theory Comput. 2022 Sep 13;18(9):5233-5245. doi: 10.1021/acs.jctc.2c00118. Epub 2022 Aug 9.
We employ our recently introduced tensor-hypercontracted (THC) second-order Møller-Plesset perturbation theory (MP2) method [Bangerter, F. H., Glasbrenner, M., Ochsenfeld, C. , , 211-221] for the computation of hyperfine coupling constants (HFCCs). The implementation leverages the tensor structure of the THC factorized electron repulsion integrals for an efficient formation of the integral-based intermediates. The computational complexity of the most expensive and formally quintic scaling exchange-like contribution is reduced to effectively subquadratic, by making use of the intrinsic, exponentially decaying coupling between tensor indices through screening based on natural blocking. Overall, this yields an effective subquadratic scaling with a low prefactor for the presented THC-based AO-MP2 method for the computation of isotropic HFCCs on DNA fragments with up to 500 atoms and 5000 basis functions. Furthermore, the implementation achieves considerable speedups with up to a factor of roughly 600-1000 compared to previous implementations [Vogler, S., Ludwig, M., Maurer, M., Ochsenfeld, C. , , 024101] for medium-sized organic radicals, while also significantly reducing storage requirements.
我们采用最近提出的张量超缩合（THC）二阶 Møller-Plesset 微扰理论（MP2）方法[Bangerter, F. H., Glasbrenner, M., Ochsenfeld, C.,,, 211-221]来计算超精细耦合常数（HFCC）。该实现利用 THC 因子化电子排斥积分的张量结构，有效地形成基于积分的中间量。通过基于自然屏蔽的筛选，利用张量指标之间固有的指数衰减耦合，有效地将最昂贵且形式上 quintic 规模的交换类似项的计算复杂度降低到次二次，从而得到有效次二次的规模。对于 THC 基 AO-MP2 方法，对于具有高达 500 个原子和 5000 个基函数的 DNA 片段上的各向同性 HFCC 的计算，总体上表现出低阶次的有效次二次规模。此外，与之前的实现[Vogler, S., Ludwig, M., Maurer, M., Ochsenfeld, C.,,, 024101]相比，该实现对于中等大小的有机自由基实现了高达约 600-1000 倍的速度提升，同时也显著降低了存储需求。
