Crystal structure of samarium hexamolybdoaluminate Sm[Al(OH)6Mo6O18] · 11H2O

The structure of a new complex of samarium(III) with a hexamolybdoaluminate ion, SmAl(OH)₆Mo₆O₁₈] · 11H₂O, was established by the methods of X-ray diffraction analysis. The crystallographic data are as follows: sp. gr. Pbc2₁, a = 10.927(4) Å, b = 11.757(5) Å, c = 22.327(9) Å, V = 2868(1) ų, Z = 4, ρ _calcd = 3.040 g/cm³, R = 0.084, R _W = 0.198. In the Al(OH)₆Mo₆O₁₈ ^3? anion, an Al atom is surrounded by six Mo atoms with distorted octahedral coordination. The anions are linked into chains via Sm atoms. The coordination polyhedron of a Sm atom is a tricapped trigonal prism with the vertices being occupied by two terminal oxygen atoms of two adjacent anions and seven water molecules.