"Chemical scissors" - a shortcut to the low-dimensional world

Abstract: A number of oxo-halide compounds have been prepared and studied. The antimony Sb3+ cation shows great flexibility in adopting coordination numbers of three or four, and, since this ion carries a stereochemically active lone-pair of electrons (E), both coordinations are one-sided. This flexibility, combined with the behaviour of the unshared electron pair, offers the possibility of a wide range of original structures to form.If late transition metals are introduced into a lone-pair element ? oxo-halide system, it is observed that the resulting structure is primarily divided into an oxygen/lone-pair element part and a halogen/transition metal part. In the majority of examples of such structures, the border between these two regions is a non-bonding volume occupied by terminal halide ions and lone-pairs of electrons. Furthermore, the halide ion – lone-pair combination acts as “chemical scissors” to reduce the dimensionality of the structure, and as a consequence the transition metals are usually forced to form chains or layers in the structures.This thesis studies some previously known Sb3+ ? O ? X (X = Cl, Br, I) compounds that lack accurate structure solution or their crystal structures remain unknown, and new compounds where a transition metal is introduced into simple antimony oxo-halide system. In all the compounds the structures formed are based on the nature of the Sb3+ cation, the behaviour of its unshared electron pair and how the structures utilize the lone-pair and halide surfaces. These compounds are examples of the concept of “chemical scissors” and the dimensionality of their structures are analysed.