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The influence of aluminium on iron oxides: XII. High-resolution transmission electron microscopic (HRTEM) study of aluminous goethites

Published online by Cambridge University Press:  09 July 2018

S. Mann ,
R. M. Cornell  and
U. Schwertmann
S. Mann
Affiliation:
Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QR, UK
R. M. Cornell
Affiliation:
University of Bern, Department of Physical and Inorganic Chemistry, Freiestrasse 3, Bern, Switzerland
U. Schwertmann
Affiliation:
Technische Universität München, Institut für Bodenkunde, 8050 Freising-Weihenstephan, FRG
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Extract

Aluminium-substituted goethites are found in many soils and can also be synthesised readily in the laboratory. In recent years, synthetic substituted goethites have been examined by various techniques including XRD, IR, TEM and dissolution kinetics (Thiel, 1963; Jonas & Solymar, 1970; Fey & Dixon, 1981; Fysh & Fredericks, 1983; Schulze & Schwertmann, 1984; Schwertmann, 1984). Transmission electron microscopy (TEM) studies have shown that as Al substitution rises above 10%, the goethite needles become shorter and also thicker in the a direction. Furthermore, crystals which at zero substitution consist of domains parallel to the c axis become less domainic with increasing Al substitution (Schulze & Schwertmann, 1984).

Type
Notes
Information
Clay Minerals , Volume 20 , Issue 2 , June 1985 , pp. 255 - 262
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1985

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References

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