Synthesis and crystal structure of [Sr(urea)(NO3)2] n

Acta Crystallogr E Crystallogr Commun. 2025 Jan 7;81(Pt 2):96-98. doi: 10.1107/S2056989024012386. eCollection 2025 Feb 1.

Abstract

The crystal structure of poly[di-μ2-nitrato-μ2-urea-strontium(II)], [Sr(NO3)2(CH4N2O)] n , was determined using single-crystal X-ray diffraction. Crystallizing in the ortho-rhom-bic space group Aba2, the asymmetric unit consists of an SrII cation, two nitrate anions, and two half urea mol-ecules. The SrII 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) Å. 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 SrII with nitrate and urea ligands, contributing to the understanding of supra-molecular architectures in metal-organic frameworks (MOFs).

Keywords: Hirshfeld surface analysis; caramid; crystal structure; strontium; urea.