Abstract
The synthesis, spectral characterization, crystal structure and properties of [Ba(H2O)2(NMF)2(4-nba)2], 1 (NMF = N-methylformamide; 4-nba = 4-nitrobenzoate), are reported. 1H and 13C NMR spectral data reveal the presence of NMF in 1. A strong band at 1660 cm−1 in the infrared spectrum indicates the binding of amide oxygen to Ba(II) which is confirmed by the single crystal structure. The unique Ba(II) in 1 situated on a mirror plane exhibits nine coordination and is bonded to two symmetry related monodentate terminal NMF ligands via the amide oxygen, and a terminal aqua ligand. The μ2-monoatomic bridging binding mode of each of a crystallographically independent 4-nba ligand and a unique water ligand link the Ba(II) cations into an infinite chain extending along a, leading to the formation of a 1D coordination polymer with Ba···Ba separations of 4.2522(3) Å. In the chain, the {BaO9} polyhedra are linked in a face sharing fashion. Thermal decomposition of 1 results in the formation of BaCO3 residue. A comparative study of the structural chemistry of several barium coordination polymers is described.
Graphical Abstract
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Acknowledgments
The authors thank the Sophisticated Analytical Instrument Facility (SAIF), Indian Institute of Technology (IIT) Madras for single crystal X-ray analysis of 1 reported in this paper. The authors thank one of the reviewers for useful suggestions.
Disclosure statement
No potential conflict of interest was reported by the authors.