Isolation and structural characterization of an octaneselenolate-protected Au25 cluster

Area of Science:

• * Inorganic Chemistry
• * Nanomaterials Science
• * Surface Chemistry

Background:

• * Gold clusters are nanoscale particles with unique electronic and catalytic properties.
• * Thiolate ligands (RS) are commonly used to stabilize gold clusters, influencing their structure and reactivity.
• * Understanding ligand effects is crucial for designing tailored gold cluster catalysts and materials.

Purpose of the Study:

• * To report the isolation and structural characterization of a novel octaneselenolate-protected gold cluster, [Au(25)(SeC(8)H(17))(18)](-).
• * To compare the structural and electronic properties of the selenolate-protected cluster with well-established thiolate-protected analogues.
• * To establish a foundation for investigating the impact of selenolate ligands on gold cluster fundamental properties.

Main Methods:

• * Isolation of the octaneselenolate-protected gold cluster using specific synthesis protocols.
• * Structural characterization employing various analytical techniques (e.g., Mass Spectrometry, NMR Spectroscopy, X-ray Diffraction - specific techniques not detailed in abstract).
• * Comparative analysis of electronic properties, focusing on charge transfer between metal core and ligands.

Main Results:

• * Successful isolation and structural confirmation of the octaneselenolate-protected Au(25) cluster, [Au(25)(SeC(8)H(17))(18)](-).
• * The [Au(25)(SeC(8)H(17))(18)](-) cluster exhibits a similar geometric structure to thiolate-protected [Au(25)(SR)(18)](-) clusters.
• * Lower charge transfer was observed between the metal atoms and selenolate ligands compared to thiolate ligands in analogous clusters.

Conclusions:

• * This study presents the first isolation of a selenolate-protected gold cluster, expanding the library of ligand-protected metal nanoclusters.
• * The findings indicate that replacing thiolate with selenolate ligands in Au(25) clusters leads to comparable structures but altered electronic properties, specifically reduced charge transfer.
• * [Au(25)(SeC(8)H(17))(18)](-) serves as a key model compound for future research on structure-property relationships in ligand-protected gold clusters.