Metal-cluster Halogen Complexes

Structures of metallic cluster complexs of Ge and Sn (for clarity only the metal and halogen atoms are shown, and the organic groups have been omitted) ... 

Preparations of metal carbonyl halide complexes containing metal-metal bonds is not a fruitful area in comparison to cleavage of metal-metal bonds by halogens. In a few cases one metal-metal bond of a cluster can be halogenated, leading to halide complexes containing metal-metal bonds. Reaction of iodine with Fc3(CO)i2 leads to a low yield of FejlCOy, ... 

As discussed in section 2.8, relativistic effects on the valence electronic structure of atoms are dominated by spin-orbit splitting of (nl) states into (nlj) subshells, and stabilization of s- and p-states relative to d- and f-states. Here we examine consequences of relativistic interactions for cubo-octahedral metal-cluster complexes of the type [M6X8Xfi] where M=Mo, Nb, W and X=halogen, which have a well defined solution chemistry, and are building blocks for many interesting crystal structures. 

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