Institute of Atomic and Molecular Physics, Key Laboratory of High Energy Density Physics and Technology, Ministry of Education, Sichuan University, Chengdu 610065, People's Republic of China.
School of Science, Xi'an University of Posts and Telecommunications, Xi'an 710121, People's Republic of China.
J Chem Phys. 2018 Jan 28;148(4):044304. doi: 10.1063/1.5011648.
We report bond lengths, force constants, and dissociation energies for a series of closed-shell superheavy element monohydrides and halides at the singles and doubles level with perturbative triples (CCSD(T)) using recently developed relativistic effective core potentials in this work. CCSD(T) results with spin-orbit coupling (SOC) included in self-consistent field (SCF) calculations provide highly accurate estimates for properties of these molecules. Trends as well as SOC effects on properties of these molecules are presented. Performance of the coupled-cluster (CC) approach with SOC included in post-SCF calculations (SOC-CC) on these superheavy element molecules is evaluated. Our results show that SOC-CCSD results are in excellent agreement with those of KR-CCSD, while the error of SOC-CCSD(T) is larger, particularly for molecules containing element 114. Density functional theory results with various exchange-correlation (XC) functionals for these superheavy element molecules are also compared with those of CCSD(T). PBE0 is shown to be able to give rise to results that agree best with those of CCSD(T) in scalar-relativistic calculations among the investigated XC functionals. On the other hand, B97-3 is the best XC functional when SOC is considered in calculations.
我们在这项工作中报道了一系列闭壳超重元素单氢化物和卤化物的键长、力常数和离解能，在单重态和双重态下使用最近开发的相对论有效核势进行了微扰三重态（CCSD(T)）计算。在自洽场（SCF）计算中包含自旋轨道耦合（SOC）的 CCSD(T)结果为这些分子的性质提供了高度准确的估计。呈现了这些分子性质的趋势以及 SOC 的影响。评估了在这些超重元素分子的后 SCF 计算（SOC-CC）中包含 SOC 的耦合簇（CC）方法（SOC-CCSD）的性能。我们的结果表明，SOC-CCSD 的结果与 KR-CCSD 的结果非常吻合，而 SOC-CCSD(T) 的误差较大，特别是对于含有 114 号元素的分子。还比较了各种交换相关（XC）泛函的密度泛函理论（DFT）结果与 CCSD(T) 的结果。在研究的 XC 泛函中，在标量相对论计算中，PBE0 被证明能够产生与 CCSD(T) 结果最吻合的结果。另一方面，在考虑 SOC 时，B97-3 是最好的 XC 泛函。
