Optimized auxiliary basis sets for density fitted post-Hartree–Fock calculations of lanthanide containing molecules

Optimised auxiliary basis sets for lanthanide atoms (Ce to Lu) for four basis sets of the Karlsruhe error-balanced segmented contracted def2 - series (SVP, TZVP, TZVPP and QZVPP) are reported. These auxiliary basis sets enable the use of the resolution-of-the-identity (RI) approximation in post Hartree–Fock methods – as for example, second-order perturbation theory (MP2) and coupled cluster (CC) theory. The auxiliary basis sets are tested on an enlarged set of about a hundred molecules where the test criterion is the size of the RI error in MP2 calculations. Our tests also show that the same auxiliary basis sets can be used together with different effective core potentials. With these auxiliary basis set calculations of MP2 and CC quality can now be performed efficiently on medium-sized molecules containing lanthanides.

本研究报道了适配卡尔斯鲁厄误差平衡分段收缩def2基组系列（包含SVP、TZVP、TZVPP与QZVPP四种基组）的镧系原子（铈Ce至镥Lu）优化辅助基组（auxiliary basis sets）。该类辅助基组可实现分辨率近似（resolution-of-the-identity，RI）在后哈特利-福克方法中的应用，例如二阶微扰理论（MP2）与耦合簇（CC）理论。我们基于包含约百余种分子的扩展测试集对该辅助基组进行了验证，测试标准为MP2计算中的RI误差大小。验证结果同时表明，该辅助基组可与不同的有效核势（effective core potentials）配合使用。借助此类辅助基组，如今可高效地对含镧系元素的中等规模分子开展MP2与CC级别的高精度计算。