A new ultraviolet transparent hydra-cyanurate K2(C3N3O3H) with strong optical anisotropy from delocalized π-bonds.
A new metal hydra-cyanurate, K2(C3N3O3H), was synthesized by a slow evaporation method in aqueous solution. It possesses a short ultraviolet cutoff wavelength at 240 nm. First-principles calculations reveal that its birefringence (∼0.35@800nm) is two times larger than that of commercial calcite crystals. Therefore, K2(C3N3O3H) and metal cyanurates, are very promising ultraviolet birefringent materials in future optical devices.