An Ultraviolet Nonlinear Optic Borate with 13-Ring Channels Constructed from Different Building Units.

Under solvothermal conditions, a chair open-framework borate, Na2B9O15(H2O)(H3O) (1), has been synthesized. Compound 1 shows regular pores of zeolites as well as nonlinear optical (NLO) properties of borates. The large 13-ring channels of the boron oxide framework are constructed from different cluster units of B3O7 and B6O13 with three-ring units. The second harmonic generation (SHG) signal intensity of 1 is similar to that of KH2PO4 (KDP) and gradually increased with larger particle size. Compound 1 is a potential UV NLO material for its short wavelength absorption edge.