The thesis deals with the activation and coordination of the reactive molecular modifications of phosphorus and arsenic. By carefully chosen reaction conditions, it is possible to selectively break one or more bonds of the native tetrahedral molecules to yield novel structural motifs. Moreover, the highly unstable yellow arsenic can be stabilized in the coordination sphere of transition metal complexes. This stabilized arsenic can be used for further reactivity studies and opens new ways in the chemistry of this fascinating element
