title: K1+2xNi1-xFe2(AsO4)3(x= 0,125): un nouvel arséniate à structure de type α-CrPO4.
abstract: A new arsenate K1+2xNi1-xFe2(AsO4)3(x= 1/8) {potassium nickel diiron(III) tris-[arsenate(V)]} was synthesized using a flux method and its crystal structure was determined from single-crystal X-ray diffraction data. This material was also characterized by qualitative energy dispersive X-ray spectroscopy (EDS) analysis. The crystal structure belongs to the α-CrPO4-structure type, space groupImma. It consists of a three-dimensional-framework built up from FeO6and Ni0.875□1.25O6-octa-hedra and AsO4-tetra-hedra that are sharing corners and/or edges, generating tunnels running along the [010] and [001] directions in which the potassium cations are located. The proposed structural model was validated by bond-valence-sum calculations, charge-distribution (CHARDI) and Madelung energy analyses.
authors.affiliation: Université de Tunis El Manar, Faculté des Sciences de Tunis, Laboratoire de Matériaux, Cristallochimie et Thermodynamique Appliquée, 2092 El Manar II, Tunis, Tunisia; Université de Carthage, Institut Préparatoire aux Etudes d'Ingénieurs de Nabeul, Campus Universitaire, 8000 Mrazka, Nabeul, Tunisia.
authors.forename: Ridha
authors.identifier: https://orcid.org/0000-0002-0807-1052
authors.initials: R
authors.lastname: Ben Smail
authors.affiliation: Université de Tunis El Manar, Faculté des Sciences de Tunis, Laboratoire de Matériaux, Cristallochimie et Thermodynamique Appliquée, 2092 El Manar II, Tunis, Tunisia.
authors.forename: Mohamed Faouzi
authors.initials: MF
authors.lastname: Zid
keywords: BVS; CHARDI; Madelung energy; arsenate; crystal structure; α-CrPO4