论文标题
施加到金属表面的Kohn-Sham交换电位的半近似值
Semilocal approximations to the Kohn-Sham exchange potential as applied to a metal surface
论文作者
论文摘要
测试了密度功能理论（DFT）框架中通常采用的几种半局限性交换潜力，并将其与其确切的对应物（交换优化有效势（OEP））进行了比较，该电位（OEP）适用于金属 - 空中界面的Jellium-SLAB模型。在其明确依赖地面密度（梯度和动能密度）的驱动下，这三个分析的半邻属交换潜力与OEP相比，其各自的渐近限制的速度比OEP更快，它们都具有形式的$-α\，e^2/z + v _} $ a = $ a} $ n y y $ n.lyly a in。在这里，我们提供了正在研究的三个模型电位的领先分析渐近学，我们发现它们都没有表现出确切的OEP板渐近级$ - \; e^2/z $。尽管所谓的Becke-Roussel势的领先渐近线接近其确切的OEP对应物，但研究中的其他两个模型电位远与真空相关的材料依赖性正恒定值，从而导致了大量高估的电离电位。
Several semilocal exchange potentials usually employed in the framework of density-functional theory (DFT) are tested and compared with their exact counterpart, the exchange Optimized Effective Potential (OEP), as applied to the jellium-slab model of a metal-vacuum interface. Driven by their explicit dependence on the ground-state density, its gradient, and its kinetic-energy density, the three analyzed semilocal exchange potentials approach their respective asymptotic limits faster than in the case of the OEP, all of them having an asymptotic scaling of the form $-α\,e^2/z + V_{\infty}$, with $α< 1$. Here we provide the leading analytic asymptotics of the three model potentials under study, and we find that none of them exhibits the exact OEP slab asymptotics $-\;e^2/z$. While the so-called Becke-Roussel potential's leading asymptote is close to its exact OEP counterpart, the other two model potentials under study approach a material-dependent positive constant value far into the vacuum, resulting in considerably overestimated ionization potentials.
