S Almeida Nuno M, Melin Timothé R L, North Sasha C, Welch Bradley K, Wilson Angela K
Department of Chemistry, Michigan State University, East Lansing, Michigan 48864, USA.
J Chem Phys. 2022 Jul 14;157(2):024105. doi: 10.1063/5.0094367.
The f-block ab initio correlation consistent composite approach was used to predict the dissociation energies of lanthanide sulfides and selenides. Geometry optimizations were carried out using density functional theory and coupled cluster singles, doubles, and perturbative triples with one- and two-component Hamiltonians. For the two-component calculations, relativistic effects were accounted for by utilizing a third-order Douglas-Kroll-Hess Hamiltonian. Spin-orbit coupling was addressed with the Breit-Pauli Hamiltonian within a multireference configuration interaction approach. The state averaged complete active space self-consistent field wavefunctions obtained for the spin-orbit coupling energies were used to assign the ground states of diatomics, and several diagnostics were used to ascertain the multireference character of the molecules.
采用f区从头算相关一致复合方法预测镧系硫化物和硒化物的离解能。使用密度泛函理论以及含单、双激发和微扰三激发的耦合簇方法，并结合单分量和双分量哈密顿量进行几何结构优化。对于双分量计算，利用三阶道格拉斯-克罗尔-赫斯哈密顿量考虑相对论效应。在多参考组态相互作用方法中，用布赖特-泡利哈密顿量处理自旋-轨道耦合。为自旋-轨道耦合能获得的态平均完全活性空间自洽场波函数用于确定双原子分子的基态，并使用多种诊断方法来确定分子的多参考特征。
