Abstract
Based on quantum mechanical calculations we predict the elastic constants of kyanite at 0 K. The reliability of the prediction has been evaluated by computing the elastic constants of andalusite and of sillimanite and comparing them to experimentally determined values. The computed bulk moduli of andalusite (145 GPa) and of sillimanite (159 GPa) are constistent with experimental values. Only two of the computed elastic contants c13 of andalusite and c23 of sillimanite differ from the experimental values by more than 11%. As the parameter-free model is transferable, the predictions for the bulk modulus, B = 178 GPa, and the elastic constants of kyanite are believed to be equally reliable. In contrast to the promising results of our quantum mechanical calculations, the agreement with experimental values is poor for elastic properties derived from a transferable empirical core-shell model.
© 2001 Oldenbourg Wissenschaftsverlag GmbH