Generation of ground‐state structures and electronic properties of ternary AlxTiyNiz clusters (x + y + z = 6) with a two‐stage density functional theory global search approach

Abstract

AbstractThe structural and electronic properties of ternary AlxTiyNiz clusters, where x, y, and z are integers and x + y + z = 6, are investigated. Both Slater, Vosko, Wilks, and Nusair and B3LYP exchange‐correlation (XC) functionals are employed in a two‐stage density functional theory (DFT) calculations to generate these clusters. In the first stage, a minimum energy cluster structure is generated by an unbiased global search algorithm coupled with a DFT code using a light XC functional and small basis sets. In the second stage, the obtained cluster structure is further optimized by another round of global minimization search coupled with a DFT calculator using a heavier XC functional and more costly basis set. Electronic properties of the structures are illustrated in the form of a ternary diagram. Our DFT calculations find that the thermodynamic stability of the clusters increases with the increment in the number of constituent nickel atoms. These results provide a new insight to the structure, stability, chemical order, and electronic properties for the ternary alloy nanoclusters.