Synthesis, crystal structure and DFT calculations of bis(1,3-diazinane-2-thione-κS)dicyanido disilver(I), [{Ag(Diaz)2}{Ag(CN)2}]

Abstract A silver(I) complex containing cyanide and diazinane-2-thione (Diaz) ligands, [Ag(Diaz) 2 Ag(CN) 2 ] ( 1 ) was prepared and its crystal structure was determined. The compound crystallizes in the orthorhombic space group, Pnma . The structure of the complex consists of [Ag(Diaz) 2 ] + cationic and [Ag(CN) 2 ] − anionic units, which are associated through Ag NC and argentophilic interactions to form a two dimensional polymeric network. An upfield shift in the C S resonance of Diaz in 13 C NMR and downfield shift in N H resonance in 1 H NMR are consistent with sulfur coordination to silver(I). The appearance of a band around 2100 cm −1 in IR and a resonance at 143 ppm in 13 C NMR indicates the binding of cyanide to silver(I). DFT calculations on model head-to-tail dimeric systems mimic the bridging behavior of the [Ag(CN) 2 ] − anionic units that connect the metal center of the cationic unit by N→Ag coordination in one N terminus, whereas the other terminal N atom is involved in hydrogen bonding towards Diaz H atoms.