[Zn(H2O)4][B6O10]: An open-framework borate with acentric structure.

An open-framework borate [Zn(H 2 O) 4 ][B 6 O 10 ] with acentric structure, has been successfully obtained for the first time under solvothermal conditions. It has been characterized by powder and single crystal X-ray diffraction, IR spectroscopy, diffuse-reflectance spectroscopy and thermogravimetric (TG) analyses, respectively. It crystallizes in the orthorhombic system, space group Pna 2 1 , a = 11.3140(6) Å, b = 11.8995(7) Å, c = 8.6140(5) Å and Z = 4. In the structure, the alternative connections between [B 3 O 7 ] units give rise to an unprecedented 3D borate framework with 11- and 10-MR channels, in which the [Zn(H 2 O) 4 ] 2+ complexes are located. It has a cut-off edge below 200 nm and exhibits second harmonic generation (SHG) efficiency approximately 0.4 times that of KH 2 PO 4 (KDP). [ABSTRACT FROM AUTHOR]