Hill Adam N, Meijer Anthony J H M, Hill J Grant
Department of Chemistry, University of Sheffield, Sheffield S3 7HF, United Kingdom.
J Phys Chem A. 2022 Sep 1;126(34):5853-5863. doi: 10.1021/acs.jpca.2c04446. Epub 2022 Aug 17.
New correlation consistent basis sets for the second-row atoms (Al-Ar) to be used with the neon-core correlation consistent effective core potentials (ccECPs) have been developed. The basis sets, denoted cc-pV(+d)Z-ccECP ( = D, T, Q), include the "tight"-d functions that are known to be important for second-row elements. Sets augmented with additional diffuse functions are also reported. Effective core polarization potentials (CPPs) to account for the effect of core-valence correlation have been adjusted for the same elements, and two different forms of the CPP cutoff function have been analyzed. The accuracy of both the basis sets and the CPPs is assessed through benchmark calculations at the coupled-cluster level of theory for atomic and molecular properties. Agreement with all-electron results is much improved relative to the basis sets that originally accompanied the ccECPs; moreover, the combination of cc-pV(+d)Z-ccECP and CPPs is found to be a computationally efficient and accurate alternative to including core electrons in the correlation treatment.
已开发出与氖芯相关一致有效核势（ccECP）一起使用的第二周期原子（Al - Ar）的新相关一致基组。这些基组表示为cc - pV(+d)Z - ccECP（= D、T、Q），包括已知对第二周期元素很重要的“紧密”d函数。还报告了用额外弥散函数增强的基组。已针对相同元素调整了用于考虑芯价相关效应的有效核极化势（CPP），并分析了两种不同形式的CPP截止函数。通过在耦合簇理论水平上对原子和分子性质进行基准计算，评估了基组和CPP的准确性。相对于最初与ccECP一起使用的基组，与全电子结果的一致性有了很大提高；此外，发现cc - pV(+d)Z - ccECP和CPP的组合是在相关处理中包含芯电子的一种计算高效且准确的替代方法。
