Guangpeng Zhou

Samarium(III) formate

The title compound, poly[samarium(III)-tri-μ-formato], [Sm(HCO2)3]n, is isostructural with numerous lanthanide formates and comprises a three-dimensional framework assembled from SmO9 polyhedra and HCO2− anions. The Sm atom lies on a site of 3m symmetry and is coordinated by nine O atoms in a typical coordination geometry. The formate anions lie on mirror planes.

Hydrothermal synthesis and characterization of two new arsenic–vanadate compounds with the same cluster anion [As8V14O42(H2O)]4−

Two new arsenic–vanadate compounds [Co(C4H13N3)2]2[As8V14O42(H2O)] · 3.5H2O (1) and (C2N2H9)2(C2N2H10)[As8V14O42(H2O)] · 2.33H2O (2) have been hydrothermally synthesized and characterized by X-ray single crystal diffraction, IR spectra and thermogravimetric analysis. Compound 1 crystallizes in the monoclinic space group P 2(1)/c, a = 24.649(9) Å, b = 13.364(5) Å, c = 22.463(8) Å, β = 104.008(5)°, V = 7180(5) Å3, Z = 4, R 1 = 0.0787, and wR 2 = 0.1859. Compound 2 crystallizes in rhombohedral system with space group R3c, a = b = c = 22.2405(5) Å, α = β = γ = 110.4030(10)°, V = 8163.4(3) Å3, Z = 6, R 1 = 0.0341 and wR 2 = 0.0941. The structural analyses show that both compounds have the same discrete cluster anion [As8V14O42(H2O)]4−. Moreover, in 1, the polyanions are connected through van der Waals forces to generate soft channels that are filled by [Co(C4H13N3)2]2+ cations and water. In 2, water and organic molecules link cluster anions to create the supramolecular assembly through hydrogen bonding.