Topotactic ion exchange is ubiquitous in the preparation of many metastable solids with layered structures. In recent times, the scope of chimie-douce ion exchange has been extended to quasi-2D and -3D structures including nanocrystals. The low-temperature solid-state exchange is yet another unique synthetic tool to access preconceived structures for the rational design of solids. Although rational synthesis using inorganic synthons is rare, few examples exist among inorganic solids with layered structures. Herein, we extend the scope further by transforming a simple perovskite (ABO₃) into a high-pressure quadruple (AA′₃B₄O₁₂) perovskite. The transformation is achieved at moderate temperatures and ambient pressure via a solid-state metathesis reaction, wherein the transition metal adopts a new A-cation coordination upon exchange. Such coordination switching upon ion exchange will open up possibilities for functionality-driven structural transformations and the rational design of new solids.

中文翻译：

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通过 NaNbO3 固态离子交换的配位转换实现简单的四重钙钛矿转变

拓扑离子交换在许多具有层状结构的亚稳态固体的制备中普遍存在。近年来，chimie-douce离子交换的范围已扩展到包括纳米晶体在内的准2D 和-3D 结构。低温固态交换是另一种独特的合成工具，可用于获取预先设想的结构以进行固体的合理设计。尽管利用无机合成子进行合理合成的情况很少见，但具有层状结构的无机固体中的例子却很少。在这里，我们通过将简单的钙钛矿（ABO ₃）转化为高压四元（AA' ₃ B ₄ O ₁₂）钙钛矿来进一步扩展范围。该转变是在中等温度和环境压力下通过固​​态复分解反应实现的，其中过渡金属在交换时采用新的A-阳离子配位。这种离子交换上的配位转换将为功能驱动的结构转变和新固体的合理设计开辟可能性。