Two Deep Ultraviolet Hydrated Borate Crystals: Centrosymmetric LiRbB5O8(OH)·H2O and Non-Centrosymmetric K2B5O8(OH)·2H2O

Two hydrated borate crystals, namely, centrosymmetric LiRbB5O8(OH)·H2O (LRB) and non-centrosymmetric K2B5O8(OH)·2H2O (K2B5), were successfully synthesized by a solvothermal technique. Although two titled compounds have the same fundamental building block B5O10(OH), the distinct linkage modes make them exhibit completely different structures. Compounds LRB and K2B5 crystallize in the nonpolar space group of P21/n and polar space group Pna21, respectively. Thermal analyses of both compounds were performed. Besides, they had short UV cutoff edge (