Aun (n = 1,11) Clusters Interacting With Lone-Pair Ligands.

Area of Science:

• Computational chemistry
• Materials science
• Surface science

Background:

• Gold clusters (Aun) exhibit unique electronic and chemical properties.
• Understanding ligand binding to gold clusters is crucial for catalysis and materials design.

Purpose of the Study:

• To analyze the binding energy patterns of small Aun clusters with various lone-pair ligands.
• To elucidate the bonding mechanisms and factors influencing binding strength.

Main Methods:

• Density Functional Theory (DFT) with PBE0 functional and dispersion correction.
• Scalar relativistic effective core potential approximation.
• Validation against benchmark coupled cluster calculations.

Main Results:

• Binding energies (BEs) of Aun-L complexes exhibit an irregular, size-dependent pattern.
• Electron affinities (EAs) of Aun clusters show an oscillatory trend with size.
• Ligand binding energies correlate with ligand ionization energies, with PX3 ligands showing the highest BEs.

Conclusions:

• The bonding mechanism involves lone pair donation and back-donation, differing between odd and even Aun clusters.
• Gold-ligand bond formation is linked to interactions with singly occupied or lowest unoccupied molecular orbitals.
• Ligand choice significantly impacts binding strength, with implications for targeted applications.