“…The interest in the activation of small molecules, such as H 2 , N 2 , NH 3 , etc., has increased notably in recent years [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 ]. A special focus lies on the activation of cage compounds such as white phosphorus and yellow arsenic by transition metals and main group compounds [ 9 , 10 , 11 , 12 ]. While the synthesis and isolation of polyphosphorus complexes have been intensively investigated [ 9 , 10 , 11 ], polyarsenic complexes are much less known, and hence the number of comparable polyarsenic complexes is quite limited [ 12 ].…”