Structural Phase Transitions and Dielectric Switching in a Series of Organic‐Inorganic Hybrid Perovskites ABX3 (X=ClO4− or BF4−)

A series of organic‐inorganic hybrid perovskites ABX3 (A=diprotonated 1,4‐diazabicyclo[2.2.2]octane or piperazine; B=Na+ or K+; X=ClO4− or BF4−) has been synthesized. They feature a cubic cage‐like host‐guest structures of which A is the cationic guest residing in the anionic cage B8X12, B is the vertex of the cage with variable coordination numbers between six and twelve, and X is the bridging ligand with mono‐ and/or bidentate coordination modes. The extended Goldschmidt tolerance factor t is used to describe the phase stability of the compounds. Differential scanning calorimetry, variable‐temperature structural analyses, and dielectric measurements reveal that order‐disorder transitions of the A guest and/or X bridging ligand are supposed to be responsible for structural phase transitions and dielectric switching in the compounds. Transform: A series of organic‐inorganic hybrid perovskites ABX3 (A=diprotonated 1,4‐diazabicyclo[2.2.2]octane or piperazine; B=Na+ or K+; X=ClO4‐ or BF4‐) has been synthesized, showing structural phase transitions and dielectric switching that are caused by order–disorder transitions of the A guest and/or X bridging ligand.