In this work, we investigated the nonlinear optical (NLO) properties of excess electron electride molecules of M[Cu(Ag)@(NH3)n](M = Be, Mg and Ca; n = 1–3) using density functional theory (DFT). This electride molecules consist of an alkaline‐earth (Be, Mg and Ca) together with transition metal (Cu and Ag) doped in NH3 cluster. The natural population analysis of charge and their highest occupied molecular orbital suggests that the M[Cu(Ag)@(NH3)n] compound has excess electron like alkaline‐earth metal form double cage electrides molecules, which exhibit a large static first hyperpolarizability ( β0e ) (electron contribution part) and one of which owns a peak value of β0e 216,938 (a.u.) for Be[Ag@(NH3)2] and vibrational harmonic first hyperpolarizability ( βzzznr ) (nuclear contribution part) values and the ratio of βzzznr / βzzze , namely, η values from 0.02 for Be[Ag@(NH3)] to 0.757 for Mg[Ag@(NH3)3]. The electron density contribution in different regions on βzzze values mainly come from alkaline‐earth and transition metal atoms by first hyperpolarizability density analysis, and also explains the reason why βzzze values are positive and negative. Moreover, the frequency‐dependent values β(−2ω,ω,ω) are also estimated to make a comparison with experimental measures. © 2018 Wiley Periodicals, Inc.

中文翻译：

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双笼过剩电子化合物非线性光学性质的密度泛函理论研究：理论设计 M[Cu(Ag)@(NH3) n ](M = Be, Mg and Ca; n = 1-3)

在这项工作中，我们使用密度泛函理论研究了 M[Cu(Ag)@(NH3)n](M = Be、Mg 和 Ca；n = 1-3) 的过量电子电极分子的非线性光学 (NLO) 特性(DFT)。这种电子化物分子由碱土金属（Be、Mg 和 Ca）以及掺杂在 NH3 簇中的过渡金属（Cu 和 Ag）组成。电荷及其最高占据分子轨道的自然布居分析表明，M[Cu(Ag)@(NH3)n] 化合物具有过量电子，如碱土金属形成双笼电子化合物分子，表现出较大的静态第一超极化率（ β0e ) (电子贡献部分) 并且其中一个拥有 Be[Ag@(NH3)2] 的峰值 β0e 216,938 (au) 和振动谐波第一超极化 ( βzzznr ) (核贡献部分) 值和 βzzznr 的比率/ βzzze ，即 η 值从 Be[Ag@(NH3)] 的 0.02 到 Mg[Ag@(NH3)3] 的 0.757。通过第一次超极化密度分析，不同区域的电子密度对βzzze值的贡献主要来自碱土金属和过渡金属原子，这也解释了βzzze值正负的原因。此外，还估计频率相关值 β(-2ω,ω,ω) 以与实验测量进行比较。© 2018 Wiley Periodicals, Inc. ω) 也估计与实验措施进行比较。© 2018 Wiley Periodicals, Inc. ω) 也估计与实验测量进行比较。© 2018 Wiley Periodicals, Inc.