Twinning and extended defects in hcp metals with large c/a ratio : modelling and microscopic observations

In hexagonal metals of largest c/a ratio, experimental observations hardly agree with the theoretical models of extended defects. For Zn and Cd, we have developed a semi-empirical tight-binding method to calculate the energy of extended defects. It was then possible to obtain a good correlation for polytypes or basal stacking faults. For the (102) twin, two possible interfaces have been shown to be stable in agreement with the available experimental results for Zn. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)