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Intracluster ligand rearrangement: an NMR-based thermodynamic study.

ABSTRACT: Ligand and metal exchange reactions are powerful methods to tailor the properties of atomically precise metal nanoclusters. Hence, a deep understanding of the mechanisms behind the dynamics that rule the ligand monolayer is crucial for its specific functionalization. Combining variable-temperature NMR experiments and dynamic-NMR simulations, we extract the thermodynamic activation parameters of a new exchange reaction: the intracluster ligand rearrangement between the two symmetry-unique positions in [Ag₂₅(DMBT)₁₈]^- and [Ag₂₄Au(DMBT)₁₈]^- clusters. We report for the first time that this peculiar intracluster modification does not seem to proceed via metal-sulphur bond breaking and follows a first-order rate law, being therefore a process independent from the well-described collisional ligand exchange.

SUBMITTER: Rosa-Gastaldo D

PROVIDER: S-EPMC10077333 | biostudies-literature | 2023 Apr

REPOSITORIES: biostudies-literature

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Intracluster ligand rearrangement: an NMR-based thermodynamic study.

Rosa-Gastaldo Daniele D Pupier Marion M Meshvildishvili Giorgi G Viger-Gravel Jasmine J Bürgi Thomas T

Nanoscale 20230406 14

Ligand and metal exchange reactions are powerful methods to tailor the properties of atomically precise metal nanoclusters. Hence, a deep understanding of the mechanisms behind the dynamics that rule the ligand monolayer is crucial for its specific functionalization. Combining variable-temperature NMR experiments and dynamic-NMR simulations, we extract the thermodynamic activation parameters of a new exchange reaction: the intracluster ligand rearrangement between the two symmetry-unique positio ...[more]

PMID: 36960796

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