Crystalline-Phase-Recognition-Induced Domino Phase Transition and Luminescence Switching for Advanced Information Encryption

Herein, a new mechanism, namely, crystalline phase recognition (CPR), is proposed for the single-crystal-to-single-crystal (SCSC) transition of metal halides. Chiral beta-[Bmmim](2)SbCl5 (Bmmim=1-butyl-2,3-methylimidazolium) can recognize achiral alpha-[Bmmim](2)SbCl5 on the basis of a key-lock feature through intercontact of their single crystals, resulting in a domino phase transition (DPT). The concomitant photoluminescence (PL) switching enables observation of the DPT in situ. The liquid eutectic interface, stress-strain transfer, and feasible thermodynamics are key issues for the CPR. DFT calculations and PL measurements revealed that the optical absorption and emission of the isomers mainly originate from [SbCl5](2-) anions. The structural effects (e.g., supramolecular interactions and [SbCl5](2-) distortion) on the optical emission are clarified. As a novel type of stimuli response, the CPR-induced DPT and luminescence switching exhibit potential for application in advanced time-resolved information encryption.

Automated summary

A new mechanism, CPR, is proposed for the SCSC transition of metal halides, where chiral molecules can recognize each other through crystalline interactions. The phase transition is accompanied by photoluminescence switching, showing potential for advanced time-resolved information encryption.