Metalloid gallium clusters

The more molecular character of 9 in comparison to 8-gallium is responsible for a decrease of the bond lengths by about 25 pm. These results prove that 9, considering its synthesis as well as the electronic structure, has to be classified in between polyhedral gallium clusters such as the square antiprismatic cluster GajjiCnHcih2- 72 and metalloid clusters. 

This section will focus on homonuclear neutral or anionic clusters of the elements aluminum, gallium, indium, and thallium, which have an equal number of cluster atoms and substituents. Thus, they may clearly be distinguished from the metalloid clusters described below, which in some cases have structures closely related to the allotropes of the elements and in which the number of the cluster atoms exceeds the number of substituents. The compounds described here possess only a single non-centered shell of metal atoms. With few exceptions, their structures resemble those of the well-known deltahedral boron compounds such as B4(CMe3)4 [30], B9CI9 [31] or [B H ]2 [32]. The oxidation numbers of the elements in these... 

However, mixtures of these products with some gallium rich metalloid clusters were formed so that this method is rather inadequate, and compounds 10-12 were isolated in very low yields. 

Metastable solutions of the monohalides AIX and GaX (X = Cl, Br, I) have been prepared using this technique, and oligomeric species (MX) -L containing a variety of donors (L) have been crystallised. The solutions disproportionate to the trihalide and the metal (equation 2) when warmed to temperatures in the range —40 to - -50°C, depending on the halide, the donor, and the concentration. Species with oxidation states both higher and lower than - -1 (i.e. on the path to both disproportionation products) have been isolated. The reduced species (0 < No. < 1) are discussed in the section on metalloid clusters, and the monohalides and more oxidized species (1 < No. < 3) are discussed here. A sonochemical synthesis of a subvalent gallium species, possibly Gal, has also been developed. 

Schnockel H, Schnepf A (2011) Aluminium and gallium clusters metalloid clusters and their relationship to the bulk phases, to naked clusters and to nanoscaled materials. In Aldridge A, Downs AJ (eds) The group 13 metals aluminium, gallium, indium and thalliiun chemical patterns and peculiarities. Wiley, Chichester, pp 402-487, Chapto 6... 

A. Schnepf, H. Schnockel, Metalloid aluminium and gallium clusters element modifications on a molecular scale Angew. Chem. Int. Ed. 41 (2002) 3532. 

From AIX/GaX Monohalide Molecules to Metalloid Aluminum and Gallium Clusters... 

This short description of the various elementary modifications of gallium shows its high structural variety, which also includes structural elements that are atypical for metals. This variety is also reflected in the inner composition of the metalloid gallium clusters, as discussed below. 

The Gag[C(SiMe3)3]6 8 cluster, which occurs as an intermediate during the formation of the Gai 9 cluster (see above), includes the most extraordinary arrangement of gallium atoms in the cluster core of all structures of metalloid gallium clusters... 

The compound [Gai9 C(SiMe3)3 6F[Li2Br(THF)6]+ contains 11, the smallest metalloid gallium cluster with a shell-like structure discussed here. The gallium core of 11 contains 19 gallium atoms, 6 of which are connected to a trisyl ligand... 

As already mentioned, 16 is the largest metalloid gallium cluster structurally analyzed so far. In addition to the 84 gallium atoms, the cluster consists of 20 N(SiMe3)2 ligands. Thus, the number of ligands is identical to that found for the... 

Metalloid Gallium Clusters GanRm< and Related Indium Clusters 2.3.4.2.1 The Modifications of Elemental Ga... 

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