The edge-sharing connection mode of BO4 tetrahedra has greatly enriched the structural chemistry of borates, which provides more options and possibilities for designing more materials with unique structures and excellent performance. A zinc borate Ba5Zn4(B3O6)2(B12O24) (BaZnBO) was synthesized via a high-temperature solid reaction. Its uniqueness lies in not only introducing Zn into the structure of β-BaB2O4 but also containing the unusual edge-sharing BO4 tetrahedra. The functional building units are isolated B3O6 and B12O24 groups. The adjacent B3O6 groups are linked to a layer in the ab plane and further stack along the 001 direction, while the B12O24 groups are located in the middle of these layers, thus forming the "sandwich" structure. This work also analyzed the impact of introducing Zn into β-BaB2O4 on the structure of anions. In addition, BaZnBO also exhibits good thermal stability and excellent optical properties including the short cut-off edge (204 nm) and suitable birefringence (0.058@1064 nm).
Liu et al. (Thu,) studied this question.