Strasburger Krzysztof
Department of Physical and Quantum Chemistry, Faculty of Chemistry, Wrocław University of Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.
J Chem Phys. 2016 Jun 21;144(23):234304. doi: 10.1063/1.4953677.
The order of low-energy states of six-electron harmonium is uncertain in the case of strong correlation, which is not a desired situation for the model system being considered for future testing of approximate methods of quantum chemistry. The computational study of these states has been carried out at the frequency parameter ω = 0.01, using the variational method with the basis of symmetry-projected, explicitly correlated Gaussian (ECG) lobe functions. It has revealed that the six-electron harmonium at this confinement strength is an octahedral Wigner molecule, whose order of states is different than in the strong confinement regime and does not agree with the earlier predictions. The results obtained for ω = 0.5 and 10 are consistent with the findings based on the Hund's rules for the s(2)p(4) electron configuration. Substantial part of the computations has been carried out on the graphical processing units and the efficiency of these devices in calculation of the integrals over ECG functions has been compared with traditional processors.
在强关联情况下，六电子钬原子低能态的顺序是不确定的，这对于未来用于测试量子化学近似方法的模型系统来说并非理想情况。这些态的计算研究是在频率参数ω = 0.01下进行的，使用了基于对称投影的显式相关高斯（ECG）瓣函数基的变分方法。结果表明，在这种限制强度下，六电子钬原子是一个八面体维格纳分子，其态的顺序与强限制 regime 不同，且与早期预测不一致。对于ω = 0.5和10所获得的结果与基于洪德规则对s(2)p(4)电子构型的研究结果一致。大部分计算是在图形处理单元上进行的，并且已将这些设备在计算ECG函数积分方面的效率与传统处理器进行了比较。
