Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99352, United States.
Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United States.
J Chem Theory Comput. 2021 Dec 14;17(12):7504-7517. doi: 10.1021/acs.jctc.1c00738. Epub 2021 Dec 2.
We present a scalable implementation of the approximation using Gaussian atomic orbitals to study the valence and core ionization spectroscopies of molecules. The implementation of the standard spectral decomposition approach to the screened-Coulomb interaction, as well as a contour-deformation method, is described. We have implemented both of these approaches using the robust variational fitting approximation to the four-center electron repulsion integrals. We have utilized the MINRES solver with the contour-deformation approach to reduce the computational scaling by 1 order of magnitude. A complex heuristic in the quasiparticle equation solver further allows a speed-up of the computation of core and semicore ionization energies. Benchmark tests using the GW100 and CORE65 data sets and the carbon 1s binding energy of the well-studied ethyl trifluoroacetate, or ESCA molecule, were performed to validate the accuracy of our implementation. We also demonstrate and discuss the parallel performance and computational scaling of our implementation using a range of water clusters of increasing size.
我们提出了一种使用高斯原子轨道来研究分子价和核心电离光谱的 近似的可扩展实现。描述了屏蔽库仑相互作用的标准光谱分解方法以及轮廓变形方法的实现。我们使用稳健的变分拟合方法对四中心电子排斥积分进行了这两种方法的实现。我们使用轮廓变形方法的 MINRES 求解器将计算规模降低了一个数量级。准粒子方程求解器中的复杂启发式方法进一步加速了核心和半核心电离能的计算。使用 GW100 和 CORE65 数据集以及经过充分研究的乙基三氟乙酸乙酯（ESCA 分子）的碳 1s 结合能进行了基准测试，以验证我们实现的准确性。我们还展示并讨论了使用一系列越来越大的水分子簇的并行性能和计算扩展。
