C8H6IN3O4: a birefringent crystal induced by uniformly aligned hybrid groups

Abstract

Herein, a novel optical crystal material, C₈H₆IN₃O₄, has been synthesized through rational design. Remarkably, C₈H₆IN₃O₄ showcases a large birefringence of 0.55@550 nm, surpassing those of commercially available birefringent materials. Theoretical calculations and analyses indicate that this phenomenon arises from the uniform alignment of π-conjugated [NO₃]⁻ and [C₈H₆IN₂O]⁺ groups.