BaSc2(HPO3)4(H2O)2: a new nonlinear optical phosphite exhibiting a 3D {[Sc2(HPO3)4]2−}∞ anionic framework and phase-matchable SHG effect

Phosphite materials have aroused wide attention due to their diverse open frameworks and promising magnetic and optical performances. Here, the first barium scandium phosphite, BaSc2(HPO3)4(H2O)2, was obtained via a facile hydrothermal route. BaSc2(HPO3)4(H2O)2 crystallizes in the polar space group Pn and exhibits a 3D {[Sc2(HPO3)4]2−}∞ anion framework constructed by distorted ScO6 octahedra and HPO32− anion groups. BaSc2(HPO3)4(H2O)2 can exhibit a phase-matchable SHG response of about 0.94 × KH2PO4 at 1064 nm, and a moderate birefringence (0.036@1064 nm) to satisfy the phase-matchable behavior requirement. Deep investigation of its structure–property relationship based on theoretical calculations has also been presented in this work.