Two cadmium compounds with adenine and carboxylate ligands: syntheses, structures and photoluminescence

Two cadmium(II) coordination compounds, [Cd3(CH3CO2)4(ad)2(CH3CN)2]n (1) and [Cd3(5-SIP)2(H-ad)2(H2O)6]n (2) (H-ad = adenine and 5-SIP = 5-sulfoisophthalate), were synthesized and characterized. Compound 1 features a two-dimensional (2-D) layered structure based on linear trinuclear [Cd3(CH3CO2)4] units bridged by monoanionic adenine ligands. In 2, the 5-SIP3− ligands link Cd(II) ions to form a one-dimensional (1-D) ladder, which is further linked by neutral adenine ligands to give a 2-D layered structure. In both structures, the carboxylate ligands link Cd(II) ions to form low-dimensional structures, which are further connected by adenine ligands to give high-dimensional structures. Compounds 1 and 2 exhibit emissions centered at 382 and 416 nm, respectively, which can be attributed to the ligand centered ππ* transition.