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

摘要

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 Au_nRe (n = 1-12) clusters. Low-lying energy structures include two-dimensional and three-dimensional geometries. Especially, for the lowest energy structures of Au_nRe (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 Au_(n+1) cluster becomes the relatively unstable odd-numbered Au_nRe cluster, while the relatively unstable even-numbered Au_(n+1) cluster becomes the relatively stable even-numbered Au_nRe 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 Au_nRe clusters is stronger than that in the corresponding Au atom of Au_(n+1). Au-Re bonds of Au_nRe clusters have stronger covalent characteristics than corresponding Au-Au bonds of Au_(n+1), meaning the stronger interaction between the Re and Au atoms than that between the corresponding Au and Au atoms in pure clusters.