The impact of relativistic effects on the periodicity of elements has significant implications for the prediction of the properties of atoms and their compounds. In this study, (non-) periodic variations of properties of Group IB dimers are investigated from the perspective of excited states. EOM-CCSD and EOM-CCSD(T)(a)* methods along with wave function analysis tools are employed to investigate their excited state. According to our results, the EOM-CCSD(T)(a)* approach with QZ basis set is required to obtain reasonable results for some states. SOC plays a crucial role in the excited state properties of Au2 and Rg2 and our results show that the ground state of Rg2 is an open-shell 2u state due to considerable SOC splitting in the 3Π state. To rationalize (non-) periodic variations of excited states, ionization potentials and electron affinities of these molecules are obtained to approximate energies of occupied and virtual orbitals. Low-lying excited states are mainly transitions from occupied orbitals to LUMO orbital for Cu2, Au2, and Rg2, while they are transitions from HOMO to virtual orbitals in Ag2. This is due to a large energy difference between HOMO and HOMO-1 in Ag2. Excited state properties of Au2 are similar to those of Cu2 when SOC is not considered due to scalar relativistic effects. The excited state properties of Rg2 differ from other molecules in the same group, as its LUMO orbital is predominantly composed of d orbitals, while they are primarily s orbitals in the other molecules.

中文翻译：

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（非）铸币金属二聚体 M2 激发态特性的周期性变化 （m = Cu， Ag， Au， Rg）


相对论效应对元素周期性的影响对原子及其化合物性质的预测具有重大意义。在这项研究中，从激发态的角度研究了 IB 组二聚体性质的（非）周期性变化。EOM-CCSD 和 EOM-CCSD（T）（a）* 方法以及波函数分析工具用于研究它们的激发态。根据我们的结果，对于某些州，需要设置了 QZ 基数的 EOM-CCSD（T）（a）* 方法才能获得合理的结果。SOC 在 Au2 和 Rg2 的激发态特性中起着至关重要的作用，我们的结果表明，由于 SOC 在 3Π 状态下发生相当大的分裂，Rg2 的基态是开壳层 2u 状态。为了合理化激发态的（非）周期性变化，获得这些分子的电离势和电子亲和力，以近似占据轨道和虚拟轨道的能量。低位激发态主要是 Cu2、Au2 和 Rg2 从占据轨道到 LUMO 轨道的跃迁，而它们是 Ag2 中从 HOMO 到虚拟轨道的跃迁。这是由于 Ag2 中 HOMO 和 HOMO-1 之间的能量差异很大。Au2 的激发态性质与 Cu2 的激发态性质相似，当由于标量相对论效应而不考虑 SOC 时。Rg 的激发态性质2 与同一组中的其他分子不同，因为它的 LUMO 轨道主要由 d 轨道组成，而它们主要是其他分子中的 s 轨道。