Synthesis and structural characterization of some 1:1 and 1:2 adducts of silver(I) salts with hindered Pmes3, PPhmes2 and PPh2mes bases (Ph = phenyl, mes = 2,4,6-trimethylpheny1))

•Influence of bulky mesityl groups in phosphines was investigated toward silver(I) salts.•Progressive substitution with less hindered phenyl groups allowed expansion of the silver environment.•Silver(I) iodide afforded a tetranuclear ‘cubane’ Ag4I4 complex and an unprecedent octanuclear complex, based on two ‘cubane’ Ag4I4 tetramers, interconnected by a central Ag(μ-I)2Ag four-membered ring.