Synthesis, structure and luminescence behaviour of a mononuclear cadmium(II) dicyanamide and a coordination polymer of mercury(II) dicyanamide containing 2,2′-dipyridylamine (dpaH) as end-capping ligand/anion of dpaH as binucleating bridge. Variance in

► Two Group 12 metal compounds [Cd(dpaH)2(dca)2] and [Hg4(dpa)4(dca)4]n are isolated. ► X-ray structures show interesting variation in coordination motifs and nuclearities. ► TG analyses show different decomposition patterns in these compounds. ► The compounds along with the bidentate tailored diimine (dpaH) are examples of luminous materials.