DECOUPLING TRANSFORMATION APPROACH TO LATTICE DYNAMICS IN FACE-CENTRED CUBIC METALS

Abstract

The Decoupling Transformation is applied to study various lattice dynamical properties of face-centred cubic metals after it is reformulated in terms of the Cyclic Region Group. The theory is established and illustrated with a running example — copper. Unique set of force constants representing interaction between intersublattices are tabulated and compared to the traditional least-squares fit results. A computer package is developed for deriving those force constants as well as for constructing the phonon spectrum based on the decoupling transformation approach. Further discussion on the approach and the results are also presented.