Trinuclear Cu(pn)2Ag2(CN)4: preparation, crystal structure and properties (pn=1,2-diaminopropane)

The new compound Cu(pn)2Ag2(CN)4 (CPAC; pn=1,2-diaminopropane) was isolated from a reaction mixture containing CuSO4, pn and K[Ag(CN)2] and was characterized by chemical analysis, IR and UV–VIS spectroscopy, and magnetic studies. The crystal structure of CPAC is built up of trinuclear NC–Ag–CN–Cu(pn)2–NC–Ag–CN molecules which are linked by hydrogen bonds and argentophilic interactions (Ag⋯Ag=3.26141(16) Å). The Cu(II) atom is coordinated in the equatorial plane by two chelate bonded pn ligands (mean Cu–N is 2.010(1) Å, while the axial positions are occupied by linear cyanoargentate anions acting as terminal ligands (Cu–N is 2.570(2) Å (2x)). The magnetic properties are well described by the Curie law down to 2 K.