Enhancing Birefringence via a Planar‐Conformation‐Locking Strategy

Here, three crystals are successfully synthesized by introducing a high polarizability birefringence‐active gene. Theoretical calculations reveal that they demonstrate birefringence values of 0.89, 0.85 and 0.82 at 550 nm, respectively, significantly exceeding those of currently available commercial birefringent crystals. This study proposes a method that employs a conformational‐locking strategy to fix the planar conformation of π ‐conjugated groups, thereby enhancing the birefringence value.