Lu, J., Liu, X., Zhao, S., Deng, X., Fu, Q., Guo, J., Liu, Z., Wu, L., Chen, L. (2026). Protonation‐Triggered Structural Transformations in 4‐Hydroxypyridinium Halides for Solar‐Blind UV Functional Crystals. Angewandte Chemie International Edition. https://doi.org/10.1002/anie.202524953