An Al12R8– cluster as an intermediate on the way from aluminium(I) compounds to aluminium metal†
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Andreas Purath, Ralf Köppe and Hansgeorg Schnöckel
Abstract
A new Al12 cluster resembling a small section of the aluminium lattice has been prepared by the reaction of AlCl solution with LiN(SiMe3)2.
References
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For the radical anion Al12(NH2)s– most of the calculated Al–Al distances are very close to those of1. A complete accordance with the experimentally determined structural data can not be expected since the NH2 ligand is different from the N(SiMe3)2 group for the following reasons. (a) The N atom in the NH2 group is pyramidally coordinated whereas a planar surrounding is observed for the N(SiMe3)2 groups. (b) The orientation of the NR2 groups towards the Al12 core should be different for both amide groups for steric reasons and therefore a different interaction of the lone pair of the N atom with the Al12 core can be expected. In order to save computing time a symmetry restriction (S4) was applied for the Al12(NH2)8 species. The electron affinity for the process Al12(NH2)8→ Al12(NH2)8– has been calculated to be exothermic by –145 kJ mol–1.
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