Experimental Confirmation of a Topological Isomer of the Ubiquitous Au25(SR)18 Cluster in the Gas Phase

Elina Kalenius; Sami Malola; María Francisca Matus; Rania Kazan; Thomas Bürgi; Hannu Häkkinen

doi:10.1021/jacs.0c11509

Experimental Confirmation of a Topological Isomer of the Ubiquitous Au₂₅(SR)₁₈ Cluster in the Gas Phase

J Am Chem Soc. 2021 Jan 27;143(3):1273-1277. doi: 10.1021/jacs.0c11509. Epub 2021 Jan 14.

Authors

Elina Kalenius¹, Sami Malola², María Francisca Matus², Rania Kazan³, Thomas Bürgi³, Hannu Häkkinen^{1

2}

Affiliations

¹ Department of Chemistry, Nanoscience Center, University of Jyväskylä, FI-40014 Jyväskylä, Finland.
² Department of Physics, Nanoscience Center, University of Jyväskylä, FI-40014 Jyväskylä, Finland.
³ Department of Physical Chemistry, University of Geneva, 30 Quai Ernest-Ansermet, 1211 Geneva 4, Switzerland.

Abstract

High-resolution electrospray ionization ion mobility mass spectrometry has revealed a gas-phase isomer of the ubiquitous, extremely well-studied Au₂₅(SR)₁₈ cluster both in anionic and cationic form. The relative abundance of the isomeric structures can be controlled by in-source activation. The measured collision cross section of the new isomer agrees extremely well with a recent theoretical prediction (Matus, M. F.; et al. Chem. Commun. 2020, 56, 8087) corresponding to a Au₂₅(SR)₁₈^- isomer that is energetically close and topologically connected to the known ground-state structure via a simple rotation of the gold core without breaking any Au-S bonds. The results imply that the structural dynamics leading to isomerization of thiolate-protected gold clusters may play an important role in their gas-phase reactions and that isomerization could be controlled by external stimuli.