Mixed azide and substituted 1,2,4-triazole co-ligand bridged 1D chain cadmium(ii) motif: crystal structure, Hirshfeld surfaces and spectroscopic studies

Abstract

A novel Cd(II) coordination polymer (1) derived from azide and 3-ethyl-4-(3-methylphenyl)-5-(2-pyridyl)-1,2,4-triazole co-ligand (L), has been synthesized and structurally characterized. Complex 1, [Cd₂(μ_1,1-N₃)₂L₂(N₃)₂]·H₂O, features a primary structure with binuclear units bridged by double asymmetric μ_1,1-azido and double terminal azide. The adjacent binuclear units are linked by two syn–syn bridged ligands L into an infinite 1D structure. Water molecules, which are located on the two sides of the binuclear unit through O–H⋯N hydrogen bond interactions with the terminal azide, supported the conversion of 1D chain structures into a 3D motif. Hirshfeld surfaces analysis revealed that the main intermolecular interactions experienced by ligand L in 1 are H–H, N–H and C–H contacts. We further investigated the Raman and IR spectra of co-ligand L, complex 1 and the dehydrated form of 1, which revealed that the dehydration of 1 does not effect the crystal structure.