It is challenging to cooperatively improve the nonlinear optical (NLO) efficiency and the laser-induced damage threshold (LIDT). This work reports a novel IR NLO materials CsInP₂S₇ (CIPS) designed by combination the strategies of alkali metals substitution and microscopic NLO units PS₄ introduction based on AgGaS₂. CIPS was composed of strongly distorted [InS₆]^9- octahedra and [P₂S₇]^4- dimers constructed by corner-sharing [PS₄]^3-, which increase the NLO efficiency and decrease thermal expansion anisotropy simultaneously. Compared with AgGaS₂, CIPS exhibited strong phase matchable NLO response ca. 1.1 × AGS@2.1 µm, high LIDT ca. 20.8 × AgGaS₂, and IR transparency up to 15.3 µm. Structural analysis and theoretical investigation confirmed that large SHG effect and ultrahigh LIDT of CIPS originated from the synergistic contribution of [InS₆]^9- octahedra and [P₂S₇]^4- dimers. These results indicate that CIPS is a promising NLO candidate in the mid-IR region, and this study provides a new approach for developing potential NLO-LIDT compatible materials.

协同提高非线性光学（NLO）效率和激光诱导损伤阈值（LIDT）具有挑战性。该工作报道了一种基于AgGaS _{2 的}新型红外非线性光学材料CsInP ₂ S ₇ (CIPS)，该材料结合了碱金属替代策略和引入微观非线性光学单元PS ₄。_{CIPS由强烈扭曲的[InS 6} ] ^9-八面体和由共享角[PS ₄ ] ^{3-构建的[P} ₂ S ₇ ] ^4-二聚体组成，可同时提高非线性光学效率并降低热膨胀各向异性。与AgGaS ₂相比，CIPS表现出较强的相位匹配NLO响应约。1.1 × AGS@2.1 µm，高 LIDT约 20.8 × AgGaS ₂，红外透明度高达 15.3 µm。结构分析和理论研究证实CIPS的大SHG效应和超高LIDT源于[InS ₆ ] ^9-八面体和[P ₂ S ₇ ] ^4-二聚体的协同作用。这些结果表明，CIPS 是中红外区域有前途的 NLO 候选材料，这项研究为开发潜在的 NLO-LIDT 兼容材料提供了一种新方法。