Elaboration, étude structurale et analyse CHARDI et BVS d'une nouvelle variété β-Na9Cr(MoO4)6 de type alluaudite

Acta Crystallographica Section E: Crystallographic Communications

Sonni, M.¹  Marzouki, R.¹  Zid, M.F.¹  Souilem, A.¹ 

[1] Laboratoire de Matériaux et Cristallochimie, Faculté des Sciences de Tunis, Université de Tunis El Manar, 2092 Manar II Tunis, Tunisia

关键词: CRYSTAL STRUCTURE;    ALLUAUDITE STRUCTURE;    FRAMEWORK;    BVS;    CHARDI;   

DOI  :  10.1107/S205698901600774X

学科分类：数学（综合）

来源: International Union of Crystallography

【 摘 要 】

The title compound, nonasodium chromium(III) hexakis[molybdate(VI)], β-Na9CrMo6O24, was prepared by solid-state reactions. This alluaudite-type structure is constituted of infinite layers formed by links between M2O10 (M = C/Na) dimers and MoO4 tetra­hedra. The Na+ and Cr3+ cations are located in the same site with, respectively, 0.25 and 0.75 occupancies. The layers are connected to each other through MoO4 sharing corners, resulting an in open three-dimensional framework with hexa­gonal-form cavities occupied by Na+ cations. The proposed structural model is supported by charge-distribution (CHARDI) and bond-valence-sum (BVS) analysis. All atoms are on general positions except for one Mo, two Na (site symmetry 2) and another Na site (site symmetry -1). A comparison is made with the similar structures Na4Co(MoO4)3, Na2Ni(MoO4)2, Cu1.35Fe3(PO4)3 and NaAgFeMn2(PO4)3.

【 授权许可】

CC BY