Identification of hyperhalogens in Agn(BO2)m (n = 1–3, m = 1–2) clusters: anion photoelectron spectroscopy and density functional calculations

Abstract

The electronic and structural properties of neutral and anionic Ag_n(BO₂)_m (n = 1–3, m = 1–2) clusters are investigated by using mass-selected anion photoelectron spectroscopy and density functional theory calculations. Agreement between the measured and calculated vertical detachment energies (VDEs) allows us to validate the equilibrium geometries of [Ag_n(BO₂)_m]⁻ clusters obtained from theory. The ground state structures of anionic Ag₂(BO₂) and Ag_n(BO₂)₂ (n = 1–3) clusters are found to be very different from those of their neutral counterparts. The structures of anionic clusters are chain-like while those of the neutral clusters are closed-rings. The presence of multiple isomers for [Ag₂(BO₂)₂]⁻ and [Ag₃(BO₂)₂]⁻ in the cluster beam has also been confirmed. Several of these clusters are found to be hyperhalogens.