6533b852fe1ef96bd12aa47b

RESEARCH PRODUCT

Dynamic Stabilization of the Ligand-Metal Interface in Atomically Precise Gold Nanoclusters Au68 and Au144 Protected by meta-Mercaptobenzoic Acid

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Ligand-stabilized, atomically precise gold nanoclusters with a metal core of a uniform size of just 1–3 nm constitute an interesting class of nanomaterials with versatile possibilities for applications due to their size-dependent properties and modifiable ligand layers. The key to extending the usability of the clusters in applications is to understand the chemical bonding in the ligand layer as a function of cluster size and ligand structure. Previously, it has been shown that monodispersed gold nanoclusters, stabilized by meta-mercaptobenzoic acid (m-MBA or 3-MBA) ligands and with sizes of 68–144 gold atoms, show ambient stability. Here we show that a combination of nuclear magnetic resonance spectroscopy, UV–vis absorption, infrared spectroscopy, molecular dynamics simulations, and density functional theory calculations reveals a distinct chemistry in the ligand layer, absent in other known thiol-stabilized gold nanoclusters. Our results imply a low-symmetry C1 ligand layer of 3-MBA around the gold cor...