Intercluster Bonds: On the Making of Extended Materials From Superatoms

Abstract

The aggregation of superatoms, serving as stable building blocks, can be understood in terms of classical chemical bonding concepts, thereby enabling a rational design of molecular materials despite their different sizes, shapes, and compositions. From this perspective, the interaction between superatomic electronic shells from different building blocks is analogous to that between atomic orbitals, yielding cluster based supermolecular counterparts of prototypical molecules. The resulting intercluster bonding modes, including single, multiple, and hybrid bonds, are found in linear, cyclic, and three-dimensional aggregates. Moreover, the notion of concentric bonding in multilayered clusters is explored, highlighting electronic interactions across nested structural layers. These insights advance the understanding of electronic structure, bonding variability, and aggregation in ligand-protected coinage metal clusters, providing a robust foundation for the rational design of superatomic materials with tailored electronic, catalytic, and optical functionalities. This framework bridges classical chemical bonding and emerging nanoscale architectures, promoting the development of cluster-based functional materials with novel properties.

Keywords

bonding / hybridization / metal clusters / superatoms / supermolecules

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