K3YB6O12: A new nonlinear optical crystal with a short UV cutoff edge

Abstract A new non-centrosymmetric borate, K 3 YB 6 O 12 , has been synthesized by solid state reaction techniques, and a K 3 YB 6 O 12 crystal with dimensions of ∼40 mm × 30 mm × 10 mm was successfully grown by the top-seeded solution growth method using a K 2 O–B 2 O 3 –KBF 4 flux. K 3 YB 6 O 12 crystallizes in the trigonal space group R32 with cell parameters of a = 13.2202(19) A, c = 30.281(6) A, and Z = 15. In the structure of K 3 YB 6 O 12 , B 5 O 10 groups are bridged by Y 3 O 12 chains and discrete YO 6 octahedra via corner-sharing, constructing columns packed side by side in a hexagonal motif along the c -axis to form a three-dimensional framework. The three-dimensional framework affords one-dimensional tunnels of 8-membered rings along the b -axis which are occupied by K atoms. K 3 YB 6 O 12 melts incongruently at 941 °C, and exhibits a short UV cutoff edge at 195 nm. The second harmonic generation effect of K 3 YB 6 O 12 is weaker than that of KH 2 PO 4 .