Development of chemical and topological structure in aluminosilicate liquids and glasses at high pressure - Université d'Orléans Accéder directement au contenu
Article Dans Une Revue Journal of Physics: Condensed Matter Année : 2015

Development of chemical and topological structure in aluminosilicate liquids and glasses at high pressure

Résumé

The high pressure structure of liquid and glassy anorthite (CaAl(2)Si(2)O(8)) and calcium aluminate (CaAl(2)O(4)) glass was measured by using in situ synchrotron x-ray diffraction in a diamond anvil cell up to 32.4(2) GPa. The results, combined with ab initio molecular dynamics and classical molecular dynamics simulations using a polarizable ion model, reveal a continuous increase in Al coordination by oxygen, with 5-fold coordinated Al dominating at 15 GPa and a preponderance of 6-fold coordinated Al at higher pressures. The development of a peak in the measured total structure factors at 3.1 Å(-1) is interpreted as a signature of changes in topological order. During compression, cation-centred polyhedra develop edge- and face- sharing networks. Above 10 GPa, following the pressure-induced breakdown of the network structure, the anions adopt a structure similar to a random close packing of hard spheres.
Fichier non déposé

Dates et versions

hal-01402115 , version 1 (24-11-2016)

Identifiants

Citer

James W.E. Drewitt, Sandro Jahn, Chrystèle Sanloup, Charlotte de Grouchy, Gaston Garbarino, et al.. Development of chemical and topological structure in aluminosilicate liquids and glasses at high pressure. Journal of Physics: Condensed Matter, 2015, 27 (10), pp.105103. ⟨10.1088/0953-8984/27/10/105103⟩. ⟨hal-01402115⟩
137 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More