Synthesis and crystal structure of [Sr(urea)(NO(3))(2)] (n).

The crystal structure of poly[di-μ(2)-nitrato-μ(2)-urea-strontium(II)], [Sr(NO(3))(2)(CH(4)N(2)O)] (n) , was determined using single-crystal X-ray diffraction. Crystallizing in the ortho-rhom-bic space group Aba2, the asymmetric unit consists of an Sr(II) cation, two nitrate anions, and two half urea mol-ecules. The Sr(II) cation adopts a distorted deca-hedral geometry coordinated by ten oxygen atoms, with Sr-O bond lengths ranging from 2.573†(3) to 2.847†(5)†à . The nitrate anions act as bidentate ligands, displaying both terminal and bridging coordination modes. The structure features a robust coordination network supported by hydrogen bonding. These results provide insight into the coord-ination behaviour of Sr(II) with nitrate and urea ligands, contributing to the understanding of supra-molecular architectures in metal-organic frameworks (MOFs).