Intermediate Intercluster Bond Orders. Electronic Communication in Au₃₈(SR)₂₄ Superatomic Molecules.

Area of Science:

• Nanomaterials Science
• Supramolecular Chemistry
• Electrochemistry

Background:

• Ligand-protected gold clusters are key components for advanced molecular materials.
• The Au38(SR)24 cluster, derived from two Au25(SR)18- units, features a bi-icosahedral Au23 core.
• Electrochemical tuning of charge states allows modification of cluster properties.

Purpose of the Study:

• To investigate the electron communication between building blocks in ligand-protected gold clusters.
• To explore the characteristics of intermediate intercluster bond orders in Au38(SR)24.
• To understand the influence of charge states on structural variations and electronic properties.

Main Methods:

• Electrochemical methods were used to tune the charge state of Au38(SR)24 clusters from -1 to +3.
• Analysis of structural variations and intercluster bond orders across different charge states.
• Investigation of unpaired electron delocalization and its impact on electron communication.

Main Results:

• Small structural variations were observed across charge states (-1 to +3) due to ligand interactions.
• Intermediate intercluster bond orders (1.5 for Au38(SR)24(1-) and (1+), 2.5 for Au38(SR)24(3+)) were identified.
• Unpaired electrons exhibited delocalized characteristics, facilitating electron communication between cluster units.

Conclusions:

• The study provides insights into electron communication in ligand-protected gold clusters.
• Delocalized electrons in charged Au38(SR)24 species promote conductive and cooperative cluster aggregates.
• Findings support the rational design of ligand-protected gold clusters for molecular electronic devices.