Achieving effective balance between bandgap and birefringence by confining π-conjugation in an optically anisotropic crystal.

Optically anisotropic crystal NaPO 2 (NH) 3 (CO) 2 achieves effective balance between wide bandgap and large birefringence owing to the π-conjugation confinement effect in the constituent [PO 2 (NH) 3 (CO) 2 ]− building units. [Display omitted] [ABSTRACT FROM AUTHOR]