BiH3 is the best reducing agent (when reducing nature increases down the group NH3 to BiH3, as in case of other hydrides of Group IVA, VIA and VIIA).
Combining the findings described in Section 2.5.1 and Section 2.5.2, one can have a different view angle of the cluster size effect. For the unsupported cases, with using the SM as the energetic reference, the stability of either IM1 or IM2 increases with the order of Ru1 < Ru2 < Ru...