ZnIO3(OH): a new layered noncentrosymmetric polar iodate – hydrothermal synthesis, crystal structure, and second-harmonic generating (SHG) properties

Abstract

A new noncentrosymmetric polar iodate material, ZnIO₃(OH), has been hydrothermally synthesized as crystals and pure powders by using ZnO (or Zn(CH₃CO₂)₂·2H₂O), HIO₃, and water. Single crystal X-ray diffraction was used to determine the crystal structure of the reported material. ZnIO₃(OH) exhibits a layered structure that is composed of ZnO₆ and IO₃ polyhedra. Powder nonlinear optical (NLO) properties measurements on ZnIO₃(OH) using 1064 nm radiation indicate the material has a second-harmonic generating (SHG) efficiency of approximately 20 times that of α-SiO₂. Additional SHG measurements reveal that the material is not phase-matchable (type 1). Infrared spectroscopy, elemental analysis, and thermogravimetric analysis for the reported compound are also presented. Crystal data: ZnIO₃(OH), monoclinic, space group Cc (no. 9) with a = 4.67670(10) Å, b = 11.2392(4) Å, c = 6.3308(2) Å, β = 90.019(2)°, and Z = 4.