Author/Authors :
Geng Bang Jin، نويسنده , , L. Soderholm، نويسنده ,
Abstract :
Colorless crystals of CsTh(MoO4)2Cl and Na4Th(WO4)4 have been synthesized at 993 K by the solid-state reactions of ThO2, MoO3, CsCl, and ThCl4 with Na2WO4. Both compounds have been characterized by the single-crystal X-ray diffraction. The structure of CsTh(MoO4)2Cl is orthorhombic, consisting of two adjacent [Th(MoO4)2] layers separated by an ionic CsCl sublattice. It can be considered as an insertion compound of Th(MoO4)2 and reformulated as Th(MoO4)2·CsCl. The Th atom coordinates to seven monodentate MoO4 tetrahedra and one Cl atom in a highly distorted square antiprism. Na4Th(WO4)4 adopts a scheelite superlattice structure. The three-dimensional framework of Na4Th(WO4)4 is constructed from corner-sharing ThO8 square antiprisms and WO4 tetrahedra. The space within the channels is filled by six-coordinate Na ions. Crystal data: CsTh(MoO4)2Cl, monoclinic, P21/c, Z=4, a=10.170(1) Å, b=10.030(1) Å, c=9.649(1) Å, β=95.671(2)°, V=979.5(2) Å3, R(F)=2.65% for I>2σ(I); Na4Th(WO4)4, tetragonal, I41/a, Z=4, a=11.437(1) Å, c=11.833(2) Å, V=1547.7(4) Å3, R(F)=3.02% for I>2σ(I).
Keywords :
Single-crystal structure , Insertion compound , Thorium , Tungstate , Molybdate