Oligocyanometallic cords as building blocks in luminescent three-dimensional coordination polymers: [Ag4Cd2(tren)2(CN)6.5][Ag(CN)1.5] and [Au2Cd(tren)(CN)4]·H2O

The syntheses, structures and luminescent properties of two unusual mixed-metal coordination polymers, namely [Ag4Cd2(tren)2(CN)7.5][Ag(CN)1.5] 1 and [Au2Cd(tren)(CN)4]·H2O 2 (tren = tris(2-aminoethyl)amine), are presented. Both compounds contain abnormal metal cords of oligocyanometallic anions as building blocks wherein the d10–d10 interaction plays a crucial role in the metal–metal assembly.