INVESTIGATION OF THE STRUCTURAL PROPERTIES OF (Au-Co-Pd)N TERNARY NANOALLOYS

Alloys and nanoalloys receive much attention because of their numerous potential applications in various fields like metallurgy, catalysis, magnetism, optics and health [1]. One of the main scientific challenge is to model their structure and properties as accurately as possible for experimentalists to the design of new materials with targeted properties. This study focuses on the structural properties of (Au-Co-Pd)N (N=19,23,26,34,38,55) ternary nanoalloys. To determine the most stable structures, the optimizations were performed by the Basin-hopping algorithm [2][3]. The Gupta many-body potential [4] was used to model interatomic interactions. To investigate the effects of composition on structural properties, the number of cobalt atoms was fixed, and the number of palladium and gold atoms was varied for all other compositions. It was predicted that the Pd and Au atoms mainly occupy the surface sites and Co atoms tend to be in the core of the ternary nanoalloys due to the lower surface and cohesive energy in comparison with palladium and gold. As a result of the performed geometry optimization, we obtained polyicosahedral structures for N=19, 23, 26 and 55 atoms. Relative stability investigation were performed using excess energy calculations. Common neighbor analysis (CNA)[5] signatures have been used for structural classifications. As a results of excess energy analyses, we obtained the most stable compositions for fixed number of Co atoms