Accurate all-electron correlation energies for the closed-shell atoms from Ar to Rn and their relationship to the corresponding MP2 correlation energies.
Accurate all-electron correlation energies for the closed-shell atoms from Ar to Rn and their relationship to the corresponding MP2 correlation energies.
复制标题
从 Ar 到 Rn 的闭壳层原子的准确全电子相关能及其与相应 MP2 相关能的关系。
DOI：
10.1063/1.3547262
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
A. Thakkar
中科院分区：
文献类型：
--
作者：
Shane P. McCarthy;A. Thakkar
对于电子数超过18的原子，全电子相关能E（c）并不是很有名。因此，在精心设计的基组耦合集团计算与完全收敛的二阶Møller-Plesset微扰理论（MP2）计算相结合，以获得相当准确的，非相对论性E（c）值的12个封闭壳层原子从Ar到Rn。这些能量将是有用的密度泛函的评价和参数化。结果表明，MP2模型高估了重原子的能隙E（c）能隙.自旋分量标度的MP2相关能量是用来提供一个简单的解释，这种高估。
All-electron correlation energies E(c) are not very well-known for atoms with more than 18 electrons. Hence, coupled-cluster calculations in carefully designed basis sets are combined with fully converged second-order Møller-Plesset perturbation theory (MP2) computations to obtain fairly accurate, nonrelativistic E(c) values for the 12 closed-shell atoms from Ar to Rn. These energies will be useful for the evaluation and parameterization of density functionals. The results show that MP2 overestimates ∣E(c)∣ for heavy atoms. Spin-component scaling of the MP2 correlation energy is used to provide a simple explanation for this overestimation.