Here, we present the synthesis and crystal structure of Rb₃InCl₆ prepared from air stable reagents via a two-step process that proceeds through the intermediate Rb₂InCl₅·H₂O. Rb₃InCl₆ crystallizes with the Rb₃YCl₆ structure type (C2/c), which can be derived from the double perovskite structure by noncooperative tilting of isolated [InCl₆]^3– octahedra. Despite this lowering of symmetry, the optical properties are similar to the cubic double perovskite Cs₂NaInCl₆. Partial substitution of In³⁺ with Sb³⁺ in Rb₃InCl₆ results in intense cyan-green photoluminescence originating from localized 5s² to 5s¹5p¹ electronic transitions of [SbCl₆]^3– polyatomic anions. In comparison with the cubic double perovskite phosphor Cs₂NaInCl₆:Sb³⁺, the octahedral tilting distortion increases the electronic isolation of the In/Sb-centered octahedra thus facilitating electron and hole localization on Sb³⁺ sites, leading to bright photoluminescence. The distorted crystal structure also leads to a larger Stokes shift (1.29 eV) and a corresponding red shift of the emission peak (λ_max = 522 nm) compared to the more symmetric Cs₂NaInCl₆:Sb³⁺ (Stokes shift ≈ 0.94 eV, λ_max = 445 nm).

中文翻译：

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Rb3InCl6：单斜双钙钛矿衍生物，具有明亮的Sb3 +激活的光致发光。

这里，我们提出Rb的合成和晶体结构₃的InCl ₆经由两步过程从空气中稳定的试剂制备，通过中间RB前进₂的InCl ₅ ·H ₂ O. RB ₃的InCl _6个结晶与Rb ₃ YCL ₆结构类型（C 2 / c），可以通过孤立的[InCl ₆ ] ^3–八面体的非合作倾斜从双重钙钛矿结构派生而来。尽管降低了对称性，但光学性质与立方双钙钛矿Cs ₂ NaInCl ₆相似。Rb ₃ InCl _6中的Sb ³⁺部分取代In ^3+会导致强烈的青绿色光致发光，其发源于[SbCl ₆ ] ^3–多原子阴离子的局部5s ²至5s ¹ 5p ¹电子跃迁。与立方双钙钛矿荧光粉Cs ₂ NaInCl ₆：Sb ^3+相比，八面体倾斜畸变增加了以In / Sb为中心的八面体的电子隔离，从而有利于电子和空穴在Sb ^3+上的局域化部位，导致明亮的光致发光。与更对称的Cs ₂ NaInCl ₆：Sb ³⁺（斯托克斯位移≈0.94 eV ）相比，扭曲的晶体结构还导致更大的斯托克斯位移（1.29 eV）和相应的发射峰红移（_λmax = 522 nm）。，_λmax = 445 nm）。