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Updated: Jul 26, 2026
Synthesis and Purification of Iodoaziridines Involving Quantitative Selection of the Optimal Stationary Phase for Chromatography
Published on: May 16, 2014
ε-La(IO3)3: A Polar Iodate with High Thermal Stability and a Large Second-Harmonic-Generation Response Obtained by a
Dandan Wang1,2, Xinyuan Zhang1, Pifu Gong3
1Tianjin Key Laboratory of Functional Crystal Materials, Institute of Functional Crystals, Tianjin University of Technology, Tianjin 300384, China.
Abstract:
The synthesis conditions at high temperature and high pressure are favorable for exploring new compounds with novel structures and properties. In this work, a new polar iodate, ε-La(IO3)3, is obtained by a supercritical hydrothermal method with high temperature and high pressure (T = 400 °C and P ≈ 25 MPa). Different from the known phases, ε-La(IO3)3 crystallizes in the chiral space group P21, which features a three-dimensional framework with multiple IO3- groups stacked along different directions around the LaO polyhedra. ε-La(IO3)3 possesses high thermal stability up to 525 °C and exhibits a wide band gap of about 4.05 eV. Attributed to its noncentrosymmetric arrangement, ε-La(IO3)3 is second-harmonic-generation (SHG)-active and the powder SHG response is measured to be 11.1 × KH2PO4 at 1064 nm in the 26-50 μm particle size range. This work has enriched the structural diversity of iodates and would further promote the materials' exploration under a supercritical hydrothermal method.
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