title: The alluaudite-like arsenate NaCaMg(3)(AsO(4))(3).
abstract: The title compound, sodium calcium trimagnesium tris-(arsenate), an alluaudite-like arsenate, was prepared by solid-state reaction at high temperature. The structure is built up from edge-sharing MgO(6) octa-hedra in chains associated with the AsO(4) arsenate groups. The three-dimensional network leads to two different tunnels occupied statistically by Na(+) and Ca(2+). One As and one Mg atom lie on twofold rotation axes; one Na and one Ca are disordered over two sites with occupancies of 0.7 and 0.3 and these sites lie on a twofold rotation axis and an inversion centre, respectively.
authors.affiliation: Laboratoire de Matériaux et Cristallochime, Institut Supérieur des Sciences Appliquées et Technologie de Mahdia, Avenue El Mourouj, Sidi Messoud 5111 Hiboun, Mahdia, Tunisia.
authors.forename: Anissa
authors.initials: A
authors.lastname: Haj Abdallah
authors.forename: Amor
authors.initials: A
authors.lastname: Haddad