Tailoring the Electron Affinity of Au₁₃ Superhalogen via Ligand Design

Abstract

The thiolate (RS)-protected neutral gold cluster Au₂₅(SR)₁₈⁰, which has an icosahedral Au₁₃ core, is regarded as a superhalogen due to its comparably high electron affinity (EA) to those of halogen atoms. Here, the EAs of Au₁₃ superhalogens protected by various thiophenolate derivatives were determined by using gas-phase photoelectron spectroscopy of the corresponding anions [Au₂₅(SR)₁₈]⁻. Correlation analysis revealed a linear relationship between the EA and the dipole moment of the RS ligands. The relationship can be explained by the concept of surface potential, which has been widely used to describe changes in the work function of bulk metals modified by self-assembled monolayers. Based on these results, we propose a unified design principle of ligand for tuning the EA of the Au₁₃ superhalogen.

Keywords

ligand-protected metal clusters / photoelectron spectroscopy / physical chemistry / superatoms

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2026 The Author(s). Aggregate published by SCUT, AIEI, and John Wiley & Sons Australia, Ltd.