Study of the Zn occupancy leading to the stability improvement for Cu6Sn5 using a first-principles approach

Abstract The influences of Zn doping on the relative stability of hexagonal and monoclinic Cu 6 Sn 5 were investigated using a first-principles approach. It was found that the phase stability of monoclinic and hexagonal Cu 6 Sn 5 could both be improved by Zn doping. For the monoclinic structure, Zn atoms preferentially occupied the 4e (Sn3) sites, it was 2c (Sn1c) sites for the hexagonal Cu 6 Sn 5 . The results of density of states demonstrated that hybridization of Zn-d and Sn-s state was the dominant factor for the stability improvement for both structures. Moreover, the Zn atoms concentration corresponding to the most stable structure for hexagonal Cu 6 (Sn,Zn) 5 was 7.54%, which was consistent with the experimental results.