Geometric evolution, stability trend and electronic properties of rhenium-doped gold clusters

Based on the density functional theory with using relativistic all electron methods, this work systematically studies the geometrical structures, relative stabilities, electronic properties, and chemical hardness of AunRe (n = 1–12) clusters. Low-lying energy structures include two-dimensional and three-dimensional geometries. Especially, for the lowest energy structures of AunRe (n = 1–12) clusters, the planar to three dimensional transformation is found to occur at cluster size n = 10 and the dopant Re atom prefers being located at highly coordinated site. After doping a Re atom, the relatively stable odd-numbered Aun+1 cluster becomes the relatively unstable odd-numbered AunRe cluster, while the relatively unstable even-numbered Aun+1 cluster becomes the relatively stable even-numbered AunRe cluster. Moreover, the presence of dopant Re atom leads to the chemical reactivity of even-numbered gold clusters becomes weaker, but the chemical reactivity of odd-numbered gold clusters turns stronger. Additionally, the spd hybridization in the Re atom of AunRe clusters is stronger than that in the corresponding Au atom of Aun+1. Au–Re bonds of AunRe clusters have stronger covalent characteristics than corresponding Au–Au bonds of Aun+1, meaning the stronger interaction between the Re and Au atoms than that between the corresponding Au and Au atoms in pure clusters.