Modelling the Morphology of Minerals by Computer

A. L. Rohl* and D. H. Gay
The Royal Institution of Great Britain, 21 Albemarle Street, London, W1X 4BS, UK
*Present address: The Inorganic Chemistry Laboratory, South Parks Road, Oxford, OX1 3QR, UK

Abstract: A new computer code (MARVIN) has been developed for the simulation of surfaces and interfaces. The models and methodologies employed within the program are briefly discussed. One application of the code, calculating crystal morphologies, is explored using zircon, quartz and α-Al2O3 as examples. The new code enables the use of covalent type force fields and the effect of surface relaxation on the growth morphology to be calculated for the first time. It is found that relaxation does affect the attachment energy but not by a large enough amount to significantly change the growth morphology for the three examples discussed here. Finally, the calculated surface relaxation for the basal plane of α-Al2O3 is found to be in complete agreement with Hartree-Fock ab initio calculations, verifying that the potentials, which are derived from bulk properties, transfer well to this surface.

Keywords: morphology • MARVIN • modelling • zircon • quartz • α-Al2O3 • corundum

Mineralogical Magazine; December 1995 v. 59; no. 397; p. 607-615; DOI: 10.1180/minmag.1995.059.397.04
© 1995, The Mineralogical Society
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