A1 Journal article (refereed)
Dynamics of weak interactions in the ligand layer of meta-mercaptobenzoic acid protected gold nanoclusters Au68(m-MBA)32 and Au144(m-MBA)40 (2020)

Mammen, N., Malola, S., Honkala, K., & Häkkinen, H. (2020). Dynamics of weak interactions in the ligand layer of meta-mercaptobenzoic acid protected gold nanoclusters Au68(m-MBA)32 and Au144(m-MBA)40. Nanoscale, 12(48), 23859-23868. https://doi.org/10.1039/d0nr07366k

JYU authors or editors

Mammen, Nisha
Malola, Sami
Honkala, Karoliina
Häkkinen, Hannu

Publication details

All authors or editors: Mammen, Nisha; Malola, Sami; Honkala, Karoliina; Häkkinen, Hannu

Journal or series: Nanoscale

ISSN: 2040-3364

eISSN: 2040-3372

Publication year: 2020

Volume: 12

Issue number: 48

Pages range: 23859-23868

Publisher: Royal Society of Chemistry (RSC)

Publication country: United Kingdom

Publication language: English

DOI: https://doi.org/10.1039/d0nr07366k

Publication open access: Openly available

Publication channel open access: Partially open access channel

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/72853

Abstract

Atomically precise metal nanoclusters, stabilized and functionalized by organic ligands, are emerging nanomaterials with potential applications in plasmonics, nano-electronics, bio-imaging, nanocatalysis, and as therapeutic agents or drug carriers in nanomedicine. The ligand layer has an important role in modifying the physico-chemical properties of the clusters and in defining the interactions between the clusters and the environment. While this role is well recognized from a great deal of experimental studies, there is very little theoretical information on dynamical processes within the layer itself. Here, we have performed extensive molecular dynamics simulations, with forces calculated from the density functional theory, to investigate thermal stability and dynamics of the ligand layer of the meta-mercaptobenzoic acid (m-MBA) protected Au68 and Au144 nanoclusters, which are the first two gold nanoclusters structurally solved to atomic precision by electron microscopy [Azubel et al., Science, 2014, 345, 909 and ACS Nano, 2017, 11, 11866]. We visualize and analyze dynamics of three distinct non-covalent interactions, viz., ligand–ligand hydrogen bonding, metal–ligand O[double bond, length as m-dash]C–OH⋯Au interaction, and metal–ligand Ph(π)⋯Au interaction. We discuss their relevance for defining, at the same time, the dynamic stability and reactivity of the cluster. These interactions promote the possibility of ligand addition reactions for bio-functionalization or allow the protected cluster to act as a catalyst where active sites are dynamically accessible inside the ligand layer.

Keywords: nanoparticles; clusters; gold; ligands

Free keywords: metal nanoclusters; organic ligands

Fields of science: