Electronic structure of Gold, Aluminum and Gallium Superatom Complexes

TL;DR

This study uses ab-initio calculations to analyze ligand-protected clusters of gold, aluminum, and gallium, revealing consistent electronic shell behavior and superatomic rules across different metals and ligands.

Contribution

It demonstrates that a superatomic electronic counting rule applies universally to these clusters, regardless of metal or ligand composition.

Findings

Clusters exhibit similar stable electronic structures.

Superatomic electronic counting rule is consistent across different metals.

Ligand-core interactions can be characterized through orbital analysis.

Abstract

Using ab-initio computational techniques on crystal determined clusters, we report on the similarities and differences of Al$_{50}$(C$_5$(CH$_3)_5)_{12}$, Ga$_{23}$(N(Si(CH$_3)_{3}$)$_{2}$)$_{11}$, and Au$_{102}$(SC$_7$O$_2$H$_5$)$_{44}$ ligand-protected clusters. Each of the ligand-protected clusters in this study show the similar stable character which can be described via a electronic shell model. We show here that the same type of analysis leads consistently to derive a superatomic electronic counting rule, independently of the metal and ligand compositions. One can define the cluster core as the set of atoms where delocalized single-angular-momentum-character orbitals have hight weight using a combination of Bader analysis and the evaluation of Khon-Sham orbitals. Subsequently one can derive the nature of the ligand-core interaction. These results yield further insight into the superatom analogy for the class of ligand-protected metal clusters.