The synthesis and structural characterization of metalloid gold clusters stabilized by sulfur ligands has increased massively in the last decade. The metalloid gold clusters are synthesized via a reduction of a gold precursor and most metalloid gold clusters are stabilized via aryl thiolate ligands. It is also possible to use thiosilyl or phosphine groups as stabilizing [a]

The increasing number of metalloid clusters, synthesized in the last couple of years, gives new insights into the formation process of metals or semi-metals. Metalloid clusters of the transition metals, especially the coinage metals are thereby of particular interest and the number of structurally characterized metalloid gold clusters has in-* Prof. Dr. A. Schnepf 670 creased over the last decade. Most of these clusters are stabilized via aryl thiolate ligands. Herein, the synthesis and crystal structures of the lithium and potassium salts of the bulky SSi(SiMe 3 ) 3 ligand are presented together with the synthesis of suitable M I precursors (M = Cu, Ag, Au) for further build-up reactions to metalloid clusters.SePh with a low steric demand. As bulky ligands, like Si(SiMe 3 ) 3 (Hyp) or N(SiMe 3 ) 2 , are useful in the chemistry of nanoscaled metalloid clusters of the elements of group 13 and 14, [9] it was wondered if it is possible to use such bulky ligands also in the chemistry of metalloid clusters of coinage metals and in the following a first step into this direction is presented.

Investigation of the correlation between the crystal structure, electronegativity difference and valence electron concentration in intermetallic gallides lead to the discovery of the new compound Ba3LiGa5 (space group Immm, a = 6.2720(2) Å, b = 6.5872(2) Å, c = 12.6878(8) Å). A combination of quantum chemical bonding analysis with NMR study revealed the gallium substructure to be formed of chains built of the interconnected pyramidal [Ga5] clusters. Analysis of chemical bonding by means of the electron localizability approach confirmed the presence nido‐[Ga5] Wade clusters. Lithium species are not only required for the purpose of charge compensation, but also – analogous to a transition metal – occupies partially the same crystallographic position as gallium.

During the search for a possible replacement of the europium in the structure Eu 3 Li 5 + x Ga 5À x (x = 0.15) in order to facilitate the analysis of the chemical bonding in the bell-like [Ga 5 ] clusters, the isostructural compound Sr 3 Li 5 Ga 5 (space group R3 m, a = 9.6040(5) Å, c = 22.061(1) Å) was discovered. A detailed investigation of the bonding situation in the first fivemembered nonconvex Ga cluster utilizing the electron localizability approach became possible, revealing not only first signs of a transition from a Zintl to a Wade cluster, but also the presence of a [Sr 6 ] polycation.

This cover picture shows the unique bell‐like [Ga5] cluster and its corresponding ELI‐D maxima, in front of a drawing of an old school bell. First observed in the related compound Eu3Li5Ga5 these clusters are the first and only known galliumclusters to be nonconvex, which makes an investigation of the intra cluster bonding of particular interest. Initially hindered by the presence of europium, an application of the electron localizability approach (ELI‐D) became possible with Sr3Li5Ga5 due to the absence of f electrons. The resulting insights into the bonding situation are described in great detail in our article 202100147.