Single-Component\nCoordination Polymers with Excitation\nWavelength- and Temperature-Dependent Long Persistent Luminescence\ntoward Multilevel Information Security

Metal–organic hybrid materials with long persistent\nluminescence\n(LPL) properties have attracted a lot of attention due to their enormous\npotential for applications in information encryption, anticounterfeiting,\nand other correlation fields. However, achieving multimodal luminescence\nin a single component remains a significant challenge. Herein, we\nreport two two-dimensional LPL coordination polymers: {[Zn<sub>2</sub>(BA)<sub>2</sub>(BIMB)<sub>2</sub>]·2H<sub>2</sub>O}<sub><i>n</i></sub> (<b>1</b>) and {[Cd(BA)(BIMB)]·3H<sub>2</sub>O}<sub><i>n</i></sub> (<b>2</b>) (BIMB = 1,3-bis(imidazol-1-yl)benzene;\nBA = butanedioic acid). Their LPL colors can be adjusted by the excitation\nwavelength or temperature variation in a single-component coordination\npolymer, achieving multimode color adjustment from green to orange\nor blue to yellow. X-ray single-crystal diffraction analysis and theoretical\ncalculations demonstrate that abundant intermolecular interactions,\nligand-to-ligand charge transfer (LLCT) transitions, and heavy atom\neffects of the central metal can realize multicolor afterglow. This\nwork provides a convenient strategy for new pattern multicolor LPL\nmaterials and may also inspire new ideas for advanced information\nencryption technologies.