Crystal structure of catena-poly[[[tri-aqua-strontium]-di-μ2-glycinato] dibromide].

In the title coordination polymer, {[Sr(C2H5NO2)2(H2O)3]Br2}n, the Sr2+ ion and one of the water mol­ecules are located on twofold rotation axes. The alkaline earth ion is nine-coordinated by three water O atoms and six O atoms of the carboxyl­ate groups of four glycine ligands, two in a chelating mode and two in a monodentate mode. The glycine mol­ecule exists in a zwitterionic form and bridges the cations into chains parallel to [001]. The Br− counter-anions are located between the chains. Inter­molecular hydrogen bonds are formed between the amino and carboxyl­ate groups of neighbouring glycine ligands, generating a head-to-tail sequence. Adjacent head-to-tail sequences are further inter­connected by inter­molecular N—H⋯Br hydrogen-bonding inter­actions into sheets parallel to (100). O—H⋯Br and O—H⋯O hydrogen bonds involving the coordinating water mol­ecules are also present, consolidating the three-dimensional hydrogen-bonding network.