Magnetic doping of a thiolated-gold superatom

TL;DR

This paper demonstrates magnetic doping of a gold superatom by replacing the central gold atom with magnetic transition metals, resulting in clusters with significant magnetic moments and magnetization of the shell.

Contribution

It introduces a novel method of magnetic doping in ligand-protected metal-cluster superatoms via atom substitution, expanding their functional potential.

Findings

Cr and Mn doping yield 5 Bohr magnetons magnetic moments.

Fe doping yields a 3 Bohr magnetons magnetic moment.

The ligand-protected shell also becomes significantly magnetized.

Abstract

The Au25(SR)18- cluster is a new member in the superatom family which features a centered icosahedral shell (Au13) protected by six RS(AuSR)2 motifs (RS- being a alkylthiolate group). Here we show that this superatom can be magnetically doped by replacing the center Au atom with Cr, Mn, or Fe. We find that Cr and Mn-doped clusters have an optimized magnetic moment of 5 Bohr magnetons while the Fe-doped cluster has an optimized magnetic moment of 3 Bohr magnetons. Although the dopant atom's local magnetic moment makes a major contribution to the total moment, the icosahedral Au12 shell is also found to be significantly magnetized. Our work here provides a new scenario of magnetic doping of a metal-cluster superatom which is protected by ligands and made by wet chemistry.