Scaling up the shape: A novel growth pattern of gallium clusters

Abstract

Putative global minima for Ga(N)⁺ clusters with size "N" ranging from 49 to 70 are found by employing the Kohn-Sham formulation of the density functional theory, and their evolution is described and discussed in detail. We have discovered a unique growth pattern in these clusters, all of which are hollow core-shell structures. They evolve with size from one spherical core-shell to the next spherical core-shell structure mediated by prolate geometries, with an increase in overall diameter of the core, as well as the shell, without putting on new layers of atoms. We also present a complete picture of bonding in gallium clusters by critically analyzing the molecular orbitals, the electron localization function, and Bader charges. Bonding in these clusters is a mixture of metallic and covalent type that leans towards covalency, accompanied by marginal charge transfer from the surface to the core. Most molecular orbitals of Ga clusters are non-jellium type. Covalency of bonding is supported by a wide localization window of electron localization function, and joining of its basins along the bonds.

The dimeric nature of bonding in gallium: from small clusters to the α-gallium phase

“…Any explanation of this phenomenon seems to rely on the nature of bonding in these small clusters being significantly different to that of the bulk, and indeed, the dimeric character of the very small clusters is lost at sizes around 10 atoms, where the first internal atom is introduced. [22][23][24][25][26] Previous work has interpreted the electron localisation function (ELF) as quantification of covalent and metallic bonding in larger Ga clusters, 27 though this interpretation is not unique 28 when considering the original interpretation of the ELF 29 and keeping in mind that chemical bonding is not an observable.…”

MeGen - generation of gallium metal clusters using reinforcement learning

“…Even for a small size like Ga 8 , MeGen model predicts some structural motifs which are missed out by DFT based search. Further the high energy isomers of Ga 8 are observed as building blocks of larger clusters with more than 30 atoms [47]. In our second experiment we generated structures of Ga 11 from seed structures of Ga 10 .…”

Multifaceted Thermodynamics of Pbn (n = 16–24) Clusters: A Case Study

“…It is interesting to note that such a partial/ characteristic similarity of atomic clusters with Jellium has been previously seen in clusters of gallium and of aluminum. 32,55 Thus, similarity of "MOs formed out of atomic s" with those of the Jellium orbitals is not just Pb specific but seems to be a trait common to other small clusters in general.…”