Zheng Xuechen, Zhang Chaoqun, Jin Zheqi, Southworth Stephen H, Cheng Lan
Department of Chemistry, The Johns Hopkins University, Baltimore, MD 21218, USA.
Department of Chemistry, University College London, London, WC1E 6BT, UK.
Phys Chem Chem Phys. 2022 Jun 8;24(22):13587-13596. doi: 10.1039/d2cp00993e.
A benchmark computational study of K-edge core-ionization energies of third-row elements using relativistic delta-coupled-cluster (ΔCC) methods and a revised core-valence separation (CVS) scheme is reported. High-level relativistic (HLR) corrections beyond the spin-free exact two-component theory in its one-electron variant (SFX2C-1e), including the contributions from two-electron picture-change effects, spin-orbit coupling, the Breit term, and quantum electrodynamics effects, have been taken into account and demonstrated to play an important role. Relativistic ΔCC calculations are shown to provide accurate results for core-ionization energies of third-row elements. The SFX2C-1e-CVS-ΔCC results augmented with HLR corrections show a maximum deviation of less than 0.5 eV with respect to experimental values.
报道了一项使用相对论性δ耦合簇（ΔCC）方法和修正的芯价分离（CVS）方案对第三周期元素K边芯电离能进行的基准计算研究。考虑了单电子变体的无自旋精确双组分理论（SFX2C-1e）之外的高级相对论（HLR）修正，包括双电子图像变化效应、自旋轨道耦合、Breit项和量子电动力学效应的贡献，并证明这些贡献起着重要作用。相对论性ΔCC计算表明能为第三周期元素的芯电离能提供准确结果。经HLR修正增强后的SFX2C-1e-CVS-ΔCC结果与实验值相比，最大偏差小于0.5 eV。
