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Removal of Arsenic Using a Cationic Polymer Gel Impregnated with Iron Hydroxide
Published on: June 28, 2019
[The arsenate Na3Fe2(AsO4) 3: structural study at low temperature and simulation of conduction properties of alkaline
Najoua Ouerfelli1, Abderrahmen Guesmi, Daniele Mazza
1Laboratoire de Matériaux et Cristallochimie, Faculté des Sciences, Université de Tunis El Manar, El Manar, 2092 Tunis, Tunisie. najoua.ouerfelli@fst.rnu.tn
Abstract:
The crystal structure of the low-temperature garnet-like form of trisodium diiron(III) triarsenate, Na(3)Fe(2)(AsO(4))(3), exhibits a three-dimensional framework with small tunnels running along the [111] direction, in which the Na(+) cations are located. This study demonstrates the structural origins of the different ionic conductivities of the low- and high-temperature forms. Sodium conduction properties are simulated by means of the bond-valence-sum (BVS) model; the correlations between the low- and high-temperature crystal structures are discussed. The As, Fe and Na atoms lie on special positions (Wyckoff symbols 24d, 16a and 24c, respectively).
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