Full-Potential KKR Calculations for Lattice Distortion Around Impurities in Al-based Dilute Alloys, Based on the Generalized-Gradient Approximation

We present systematically the calculated results for the lattice distortion caused by the substitutional two impurities (X-X pairs; X=Sc-Ge) in Al, being located at the 1st-nearest neighboring sites. The calculations are based on the generalized-gradient approximation in the density functional theory and the full-potential Korringa-Kohn-Rostoker (FPKKR) Green's function method for point defects. The distortion effect is very large for the present impurity systems, especially for X=Mn, Fe, and Co. The interatomic length of the X-X pair extends for X=Cr, Mn, Fe, Co, and Ni, although the atomic size of these impurities is fairy smaller than the atomic size of Al. We clarify the micromechanism of the lattice distortion caused by the X-X pair.