ATh_(12)N_6X_(29) (A = Li... Rb; X = Cl, Br): A New Type of Thorium Cluster with a Th_(12)N_6 Core

摘要

The reduced halides of the rare earth elements exhibit a rich chemistry, in which discrete or condensed metal clusters, play a major role. Primarily the 5d electrons are involved in metal-metal bonds in the clusters; the 4f electrons are much lower inenergy. The possible participation of f electrons in the formation of metal-metal bonds is still in question. One prerequisite for this is significantly higher energies, as found in the 5 f metals. We therefore started experiments to prepare reduced thorium halides as a "window towards the actinoids". Like the related element zirconium, thorium forms cluster compounds if interstitial heteroatoms are allowed for stabilization. We have already reported on thorium cluster compounds with an octahedral Th_6Br_(15) unit, and we now describe compounds with the new cluster framework Th_(12)Br_(29).