Crystal structure of the mineral strontiodresserite from laboratory powder diffraction data

Par Conseil national de recherches du Canada

Téléchargement	Voir le manuscrit accepté : Crystal structure of the mineral strontiodresserite from laboratory powder diffraction data (PDF, 611 Kio)
DOI	Trouver le DOI : https://doi.org/10.1154/1.3504496
Auteur	Rechercher : Whitfield, P. S.¹; Rechercher : Mitchell, L. D.²; Rechercher : Le Page, Y.¹; Rechercher : Margeson, J. C.²; Rechercher : Roberts, A. C.
Affiliation	Conseil national de recherches du Canada. Institut de technologie des procédés chimiques et de l'environnement du CNRC Conseil national de recherches du Canada. Institut de recherche en construction du CNRC
Format	Texte, Article
Sujet	mineral, charge-flipping, simulated annealing, Rietveld refinement
Résumé	The crystal structure of the mineral strontiodresserite, (Sr,Ca)Al2(CO3)2(OH)4⋅H2O, from the Francon Quarry, Montreal, Quebec, Canada, has been solved from laboratory powder diffraction data using a combination of charge-flipping and simulated annealing methods. The structure is orthorhombic in space group Pnma with a=16.0990(7), b=5.6133(3), and c=9.1804(4) Å (Z=4) and the framework of the mineral is isostructural with that of dundasite. The strontium has a coordination number of 9 and the carbonate anions form a bridge between the SrO9 polyhedra and AlO6 octahedra. The water molecule lies in a channel that runs parallel to the b axis. An ordered network of hydrogen atoms could be uniquely determined from crystal-chemical principles in the channels of strontiodresserite. Ab initio density functional theory (DFT) energy minimization of the whole structure gave results in full agreement with X-ray refinement results for nonhydrogen atoms. The stability of this model (as well as that of the corresponding model of dundasite) in the proposed Pnma space group was tested by DFT optimization in space group P1 of random small distortions of this structure. This test confirms that both minerals are isostructural, including their hydrogen-bond networks.
Date de publication	2010-12-01
Dans	Powder Diffraction Journal 25, nº 4 (1 décembre 2010) : 322–328.
Langue	anglais
Publications évaluées par des pairs	Oui
Numéro du CNRC	NRCC 53597 NRC-IRC-21323
Numéro NPARC	20374704
Exporter la notice	Exporter en format RIS
Signaler une correction	Signaler une correction (s'ouvre dans un nouvel onglet)
Identificateur de l’enregistrement	04c9e819-8dc9-429a-a02b-6f497bf5198c
Enregistrement créé	2012-07-23
Enregistrement modifié	2020-04-17

Date de modification :: 2024-07-17