To design pnictide nonlinear optical materials with wide band gap and large second‐harmonic generation, the heavy halogen I was introduced into pnictides through anionic aliovalent substitution with diamond‐like ZnS as templates. Thus, four excellent halopnictide‐based infrared nonlinear optical crystals, M^II₃PnI₃ (M^II=Zn, Cd; Pn=P, As), were obtained. They all exhibited defect diamond‐like structures with highly parallel‐oriented [M^IIPnI₃] mixed‐anionic tetrahedral groups, leading to excellent physical properties including wide band gaps (2.38–2.85 eV), large second harmonic generation responses (2.7–5.1×AgGaS₂), high laser‐induced damage thresholds (5.5–10.7×AgGaS₂), and good IR transparency. In particular, Cd₃PI₃ and Cd₃AsI₃ achieved phase‐matching (Δn=0.035 and 0.031) that their template β‐ZnS could not do. Anionic aliovalent substitution provides a feasible strategy to design novel promising halopnictide IR NLO materials.

中文翻译：

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ZnS的结构模型中的阴离子异价取代：具有宽带隙和大SHG效应的新型缺陷类金刚石类卤化物红外非线性光学材料。

为了设计具有宽禁带宽度和较大二次谐波生成量的光子非线性光学材料，通过以钻石状ZnS作为模板的阴离子异价取代将重卤素I引入到光子中。因此，获得了四种出色的基于卤虫肽的红外非线性光学晶体M ^II ₃ PnI ₃（M ^II = Zn，Cd； Pn = P，As）。它们都显示出具有高度平行[M ^II PnI ₃ ]混合阴离子四面体基团的缺陷类金刚石结构，从而导致出色的物理性能，包括宽带隙（2.38–2.85 eV），大的二次谐波响应（2.7–5.1） ×AgGaS ₂），高激光诱导损伤阈值（5.5-10.7×AgGaS₂），以及良好的红外透明性。特别是Cd ₃ PI ₃和Cd ₃ AsI ₃实现了模板β-ZnS不能实现的相位匹配（Δn = 0.035和0.031）。阴离子异价取代为设计新颖的有希望的卤代核苷酸IR NLO材料提供了可行的策略。