Hydrothermal Synthesis of Rare Earth Iodates from the Corresponding Periodates: Structures of Sc(IO3)3, Y(IO3)3 · 2 H2O,La(IO3)3 · 1/2 H2O and Lu(IO3)3 · 2 H2O

Hydrothermal syntheses of single crystals of rare earth iodates, by decomposition of the corresponding periodate, are presented. This appears to be a generic method for making rare earth iodate crystals in a short period of time. Single crystal X‐ray diffraction structures of the four title compounds are presented. Sc(IO₃)₃: Space group R3, Z = 6, lattice dimensions at 100 K; a = b = 9.738(1), c = 13.938(1) Å; R₁ = 0.0383. Y(IO₃)₃ · 2 H₂O: Space group P1, Z = 2, lattice dimensions at 100 K: a = 7.3529(2), b = 10.5112(4), c = 7.0282(2) Å, α = 105.177(1)°, β = 109.814(1)°, γ = 95.179(1)°; R₁ = 0.0421. La(IO₃)₃ · ? H₂O: Space group Pn, Z = 2, lattice dimensions at 100 K: a = 7.219(2), b = 11.139(4), c = 10.708(3) Å, β = 91.86(1)°; R₁ = 0.0733. Lu(IO₃)₃ · 2 H₂O: Space group P1, Z = 2, lattice dimensions at 120 K: a = 7.2652(9), b = 7.4458(2), c = 9.3030(3) Å, α = 79.504(1)°, β = 84.755(1)°, γ = 71.676(2)°; R₁ = 0.0349.