Electron Affinities of Ligated Icosahedral M₁₃ Superatoms Revisited by Gas-Phase Anion Photoelectron Spectroscopy.

ABSTRACT: The electron binding energies of the ligand-protected gold/silver-based cluster anions, [Au₂₅(SR)₁₈]^-, [XAg₂₄(SR')₁₈]^2- (X = Ag⁺, Au⁺, Pd⁰, or Pt⁰), and [PdAu₂₄(C≡CR″)₁₈]^2- having icosahedral M₁₃ superatomic cores, were reexamined by gas-phase photoelectron spectroscopy (PES) on a significantly intensified mass-selected ion beam. Laser fluence-dependent PE spectra and pump-probe PES revealed that the previous PE spectra were contaminated by PE signals due to the two-photon electron detachment via long-lived photoexcited states. Although the adiabatic electron affinities (AEAs) of the corresponding oxidized forms were found to be 1-2 eV larger than those previously reported, the effects of doping and ligation were not qualitatively affected. (1) The AEA of the Ag₁₃ superatom (∼4 eV) was not appreciably affected by doping a Au atom at the center but was reduced by ∼2 eV by doping Pd or Pt, and (2) the AEA of PdAu₁₂ protected by Au₂(C≡CR″)₃ units was much larger than that of PdAg₁₂ protected by Ag₂(SR')₃ units.

SUBMITTER: Ito S 

PROVIDER: S-EPMC9190706 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature