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X-ray powder diffraction analysis of the heteropoly-molybdate (MoO2)0.5PMo14O42

Published online by Cambridge University Press:  06 March 2012

L. Marosi
Affiliation:
Departamento de Química, Universidad de las Islas Baleares, 07071 Palma de Mallorca, Spain
J. Cifré
Affiliation:
Departamento de Química, Universidad de las Islas Baleares, 07071 Palma de Mallorca, Spain
C. Otero Areán*
Affiliation:
Departamento de Química, Universidad de las Islas Baleares, 07071 Palma de Mallorca, Spain
*
a)Author to whom correspondence should be addressed: C. Otero Areán, Departamento de Química, Universidad de las Islas Baleares, 07071 Palma de Mallorca, Spain, Electronic mail: dqueep0@clust.uib.es, Fax: (+34) 971 173426.

Abstract

The new heteropoly blue compound (MoO2)0.5PMo14O42, which is relevant in the context of catalytic activity of heteropoly-molybdates, was prepared by controlled thermolysis of (NH4)3PMo12O40 at 730 K in a nitrogen atmosphere. Powder X-ray diffraction analysis showed that this compound has a cubic unit cell, space group Pn3m (No. 224), with ao=11.795(2) Å, Z=2 and DXR=4.2466 g cm−3. Computer modeling and Rietveld analysis of powder diffraction patterns led to a proposed structure of the corresponding Keggin-cage unit PMo14O42.

Type
New Diffraction Data
Copyright
Copyright © Cambridge University Press 2005

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