Heterometallic cuboidal clusters [M.sub.3]M'[Q.sub.4](M=Mo, W; M'=Sn, Pb, As, Sb; Q=S, Se): from coordination compounds to supramolecular adducts

Incomplete cuboidal clusters when reacted with group 14 and 15 metal complexes with [s.sup.2][p.sup.0] electronic configuration resulted in the formation of heterometal incorporated cuboidal clusters. X-ray diffraction studies showed the cuboidal clusters as weak complexes of the cluster tridentate ligand with [EX.sub.3].