Synthesis and characterization of an Al(69)(3-) cluster with 51 naked Al atoms: analogies and differences to the previously characterized Al(77)(2-) cluster.
A disproportionation process of a metastable AlCl solution with a simultaneous ligand exchange-Cl is substituted by N(SiMe(3))(2)-leads to a [Al(69)[N(SiMe(3))(2)](18)](3-) cluster compound that can be regarded as an intermediate on the way to bulk metal formation. The cluster was characterized by an X-ray crystal structural analysis. Regarding its structure and the packing within the crystal, this metalloid cluster with 4 times more Al atoms than ligands is compared to the [Al(77)N(SiMe(3))(2)](20)](2-) cluster that has been published four years ago. Although there is a similar packing density of the Al atoms in both clusters as well as in Al metal, the X-ray structural analysis shows significant differences in topology and distance proportions. The differences between these-at a first glance almost identical-Al clusters demonstrate that results of physical measuring, e.g., of nanostructured surfaces which carry supposedly identical cluster species, have to be interpreted with great caution.
Köhnlein
H
H
Institut für Anorganische Chemie, Universität Karlsruhe (TH), Engesserstrasse, Geb. 30.45 D-76128 Karlsruhe, Germany.
Purath
A
A
Klemp
C
C
Baum
E
E
Krossing
I
I
Stösser
G
G
Schnöckel
H
H