Three New Organically Templated 1D, 2D, and 3D Vanadates: Synthesis, Crystal Structures, and Characterizations

Three new vanadate compounds of the formulas (C2N2H10)VO(OH)4 (I), (NH4)3(C3N2H5)V4O10 (II), and V(OH)3·0.97H2O (III) have been synthesized by a solvothermal method and characterized by IR spectroscopy, elemental
analysis, and thermogravimetric analysis. The crystal structures of the above three vanadates have been established
by single-crystal X-ray diffraction. Compound I crystallizes as tetragonal, space group P4/mmm, with a = 9.0465(11) Å, c = 3.9897(10) Å, V = 326.51(10) Å3, and Z = 2. Compound II crystallizes as orthorhombic, space group
Immm, with a = 3.6012(10) Å, b = 11.312(4) Å, c = 15.050(4) Å, V = 613.1(3) Å3, and Z = 2. Compound III
crystallizes as cubic, space group Fd3̄m, with a = 10.4252(17) Å, V = 1133.1(3) Å3, and Z = 16. Structural
analyses reveal a one-dimensional beeline-chained structure, which consists of VO6 octahedra in I. Compound II
possesses a two-dimensional V−O-layered structure formed by VO5 square pyramids; protonated imidazole and
remaining NH4+ cations are inserted between the layers. The three-dimensional open framework of III with the
pyrochlore type consists of V12 and V4 secondary building units by using VO6 octahedra as building units.