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The crystal structure of Mg end-member lizardite-1T forming polyhedral spheres from the Lizard, Cornwall

Published online by Cambridge University Press:  05 July 2018

M. Mellini ,
G. Cressey ,
F. J. Wicks  and
B. A. Cressey
M. Mellini
Affiliation:
Dipartimento di Scienze della Terra, Università di Siena, Via Laterina 8, 53100 Siena, Italy
G. Cressey*
Affiliation:
Department of Mineralogy, Natural History Museum, Cromwell Road, London SW7 5BD, UK
F. J. Wicks
Affiliation:
Natural History Department, Royal Ontario Museum, 100 Queen's Park, Toronto M5S 2C6, Canada
B. A. Cressey
Affiliation:
Electron Microscopy Centre, School of Chemistry, University of Southampton, Southampton SO17 1BJ, UK
*
*E-mail: g.cressey@nhm.ac.uk
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Abstract

The crystal structure of lizardite-1T from Gew-graze, Cornwall, has been refined by single-crystal X-ray diffraction to R1 of 0.0263 and 0.0557, for two crystals having P31m space group and lattice parameters a = 5.2905(5) Å, c = 7.2815(8) Å, and a = 5.3111(10) Å, c = 7.2907(15) Å, respectively. The Gew-graze lizardite is very close to the end-member composition, so these refinements confirm the existence of well crystallized pure Mg-lizardite and show this to be the most weakly H-bonded lizardite ever refined. With regard to its lattice parameters, Si–O bond distances and geometrical parameters controlled by interlayer interactions (i.e. H-bonding), the Gew-graze Mg end-member lizardite yields slight but observable geometrical differences compared with previous refined structures for specifically, aluminous, lizardites.

Keywords

serpentinepolyhedral sphereslizarditestructure
Type
Research Article
Information
Mineralogical Magazine , Volume 74 , Issue 2 , April 2010 , pp. 277 - 284
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2010

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Supplementary material: File

Mellini et al. supplementary material

Structure factors 1

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Mellini et al. supplementary material

Strucure Factors 2

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