Lock-and-Key Assembly Enables Record Birefringence in Monocyclic π-Conjugated Crystals via Spatial Confinement of Linear Polyhalide. - Hu YX; Yu Wu H; Li JJ; Wang MC; Lian JM; Yu Luo J; Fu YR; Chen ZY; Guo YH; Chen J; Du KZ (Angewandte Chemie (International ed. in English), 2026)