Planar σ-Aromaticity in Ga-Doped Au Clusters.

Area of Science:

• Computational chemistry
• Materials science
• Cluster physics

Background:

• The synthesis of the first Au-Ga clusters opens new avenues in superatom chemistry.
• Understanding the electronic structure and stability of doped clusters is crucial for novel material design.

Purpose of the Study:

• To analyze the structural features and stability of Ga-doped Au clusters with specific magic electron numbers (6 and 8).
• To investigate the valence electron fillings, chemical bonding, and aromaticity of Au3Ga and Au5Ga clusters.

Main Methods:

• Density Functional Theory (DFT) calculations for structural and electronic properties.
• Ab initio molecular dynamics (AIMD) simulations for thermal stability assessment.
• Molecular orbital analysis, Electron Localization Function (ELF), and Natural Population Analysis (NPA) for bonding and aromaticity.
• NICSzz-scan curves to quantify aromaticity.

Main Results:

• Au3Ga and Au5Ga clusters adopt stable planar configurations with magic electron counts.
• These planar clusters exhibit significant thermal stability up to 500 K.
• Molecular orbital analyses confirm planar σ-aromaticity, with Au3Ga showing higher aromaticity than Au5Ga due to more delocalized electrons.

Conclusions:

• Ga-doped Au clusters, specifically Au3Ga and Au5Ga, demonstrate unique planar structures and enhanced stability.
• The study establishes planar σ-aromaticity in these Au-Ga clusters, expanding the scope of aromaticity research.
• These findings pave the way for exploring novel electronic and chemical properties of Au-Ga superatomic systems.