LiMoO3(IO3): A new molybdenyl iodate based on WO3-type sheets with large SHG response

A novel lithium molybdenyl iodate, LiMoO3(IO3), has been prepared by hydrothermal reactions at 170 °C. Its crystal structure has been determined from single-crystal X-ray data: space group P21, a = 5.4104(4) Å, b = 5.3158(3) Å, c = 9.0025(7) Å, β = 106.863(6)°, Z = 2. LiMoO3(IO3) is a new layered material containing [MoO3(IO3)]1−[MoO3(IO3)]1− anionic layers separated by Li+ cations. The anionic layer has an unprecedented configuration consisting of WO3-type sheets “capped” by IO3− groups. The iodate groups have their stereochemically active nonbonded electron pairs align along the b-axis, which creates the polarity in the structure. Second-harmonic-generation measurements on LiMoO3(IO3) display a response of about 4 × KH2PO4. DTA measurements demonstrate that LiMoO3(IO3) is stable up to at least 430 °C. UV–vis diffuse reflectance spectrum of this compound shows a high degree of transparency from 1.1 to 2.8 eV and a band gap of about 2.8 eV.