Observation of halogen-like behavior of gold in fluorinated bimetallic CoAuF_1-2⁻ and CuAuF_1-2⁻ clusters: Anion photoelectron spectroscopy and density functional theory.

This article focuses on the investigation of the structural and electronic properties of fluorinated bimetallic clusters CoAuF₁₋₂⁻ and CuAuF₁₋₂⁻ and their neutral counterparts using size-selected anion photoelectron spectroscopy and density functional theory (DFT). The study reveals that in these clusters, gold (Au) exhibits halogen-like behavior by mimicking fluorine (F) in terms of charge distribution, electronic configuration, and bonding characteristics, with Au forming ionic bonds similar to M–F (M = Co, Cu) bonds. Experimental vertical detachment energies (VDEs) of CoAuF⁻ and CuAuF⁻ closely match those of CoF₂⁻ and CuF₂⁻, respectively, while the addition of a second fluorine atom results in CoAuF₂⁻ and CuAuF₂⁻ clusters exhibiting superhalogen properties, with VDEs exceeding those of typical halogen anions. These findings contribute to a deeper understanding of gold's nanoscale properties relevant to catalysis and nanotechnology.