论文标题
超轨道，轨道分裂和纯碱金属簇的结构预测
Superatom Orbitals, Orbital Splitting and Structure Prediction of Pure Alkali Metal Clusters
论文作者
论文摘要
Jellium模型在预测具有闭合电子壳和零旋转的稳定簇方面取得了巨大成功。为了解释开放壳簇的稳定性，有必要考虑非分类能级的情况。在本文中，通过超级原子轨道分裂效果系统地分析了九个低洼的li $ _ {19} $簇中的能量水平。已经发现，对于最初具有五个1D轨道的简化轨道，轨道沿簇延伸的方向延伸的越多，轨道的能量就越低。因此，将li $ _ {19} $簇具有轨道序列美元X^2-Y^2}^{4} -2 \ Mathrm {s}^2-1 \ Mathrm {d} _ {XZ/Yz}^{4} {4} -1 \ Mathrm {d} _ {Z^2}而prate li $ _ {19} $簇的顺序$ 1 \ mathrm {s}^2-1 \ Mathrm {p} _ {z}^{2} {2} -1 \ Mathrm {p} _ {x/y}^{4}^{4} -1 \ Mathrm {d} }^{2} -1 \ Mathrm {d} _ {xz/yz}^{4} -1 \ Mathrm {d} _ {xy/x^2-y^2}^{4}^{4} {4} -2 \ 2 \ Mathrm {s}}^1 $。该电子构型用于预测碱金属li $ _ {n} $簇的形状和磁矩。 Li $ _ {14} $群集的稳定性可以在轨道分裂效果的框架中成功解释，而无需诉诸于超级价值键（SVB）模型，这表明非球形群集可以实现良好的稳定性而无需满足魔术数。还提出，轨道分裂可用于预测簇的形状（岩层，扁平或球体）和磁矩。在16个李$ _n（n = 3-18）$的16个预测形状中，有11个与最低能量原理获得的结果一致。
Jellium model achieved great success in predicting stable clusters with closed electronic shells and zero spin. In order to explain the stability of open shell clusters, it is necessary to consider the case of non-degenerate energy levels. In this paper the energy levels in nine low-lying Li$_{19}$ clusters are analysed systematically through superatomic orbital splitting effect. It is found that for originally degenerate orbitals like five 1D orbitals, the more the orbital extends in the direction of the cluster extension, the lower the energy of the orbital becomes. So oblate Li$_{19}$ clusters have the orbital sequence of $1\mathrm{S}^2-1\mathrm{P}_{x/y}^{4}-1\mathrm{P}_{z}^{2}-1\mathrm{D}_{xy/x^2-y^2}^{4}-2\mathrm{S}^2-1\mathrm{D}_{xz/yz}^{4}-1\mathrm{D}_{z^2}^{1}$, while prolate Li$_{19}$ clusters have the sequence of $1\mathrm{S}^2-1\mathrm{P}_{z}^{2}-1\mathrm{P}_{x/y}^{4}-1\mathrm{D}_{z^2}^{2}-1\mathrm{D}_{xz/yz}^{4}-1\mathrm{D}_{xy/x^2-y^2}^{4}-2\mathrm{S}^1$. This electron configuration is applied to predict the shape and magnetic moment of the alkali metal Li$_{n}$ clusters. The stability of the Li$_{14}$ cluster can be successfully interpreted in the framework of orbital splitting effect without resorting to the super valence bond (SVB) model, indicating a non-spherical cluster can achieve good stability without meeting the magic number. It is also proposed that the orbital splitting can be used to predict the shape (prolate, oblate or sphere) and magnetic moment of clusters. 11 out of 16 predicted shapes of Li$_n(n=3-18)$ are consistent with the results obtained by the principle of minimum energy.
