Date Published: May 01, 2012
Publisher: International Union of Crystallography
Author(s): Anissa Haj Abdallah, Amor Haddad.
The title compound, potassium strontium trialuminium tetraarsenate, was prepared by solid-state reaction. The structure consists of AlO6 octahedra (site symmetries 2.. and 2/m) and two AsO4 tetrahedra (.2. and m..) sharing corners and edges to form a two-dimensional structure parallel to (010). The cations are occupationally disordered and are located in the interlayer space. For both types of cations, distorted coordination polyhedra are observed.
For further information on this structure type, see: K3Cr3(AsO4)4 (Friaa et al., 2003 ▶); K3Fe3(AsO4)4 (Ouerfelli et al., 2005 ▶). For similar structures, see: K3Fe3(PO4)4·H2O (Lii, 1995 ▶); Na3Fe3(PO4)4 (Lajmi et al., 2002 ▶). For background to the bond-valence method, see: Brown & Altermatt (1985 ▶).