The complex structure of liquid Cu6Sn5 alloy

By applying ab initio molecular dynamics simulation to liquid Cu6Sn5 alloy, the hetero-coordination tendency is discovered by Bathia-Thornton partial correlation functions and a chemical short-range parameter. However the local structural environment of Sn in l-Cu6Sn5 alloy resembles that of liquid Sn by Voronoi analysis. A new feature, i.e. a subpeak in between the first and second peaks, is discovered by the present method which implies that topologically disordered β-Sn-type structural units may exist in l-Cu6Sn5 alloy. The local density states of electrons show that both Cu-Sn and Sn-Sn bonding exist in l-Cu6Sn5 alloy. This work suggests that chemical short-range order between unlike atoms and self-coordination between Sn atoms coexists in l-Cu6Sn5 alloy.