Crystal structures and luminescence properties of a one-dimensional cadmium coordination polymer derived from a flexible bis(imidazole) ligand

Abstract

A new Cd(II) coordination polymer, namely [Cd(pbmb)(mip)]n (pbmb = 1,1′-(1,3-propane)bis-(2-methylbenzimidazole), H₂mip = 5-methylisophthalic acid), is hydrothermally synthesized and characterized by elemental analyses, infrared spectroscopy and single crystal X-ray diffraction analyses. It crystallizes in the triclinic space group \(P\overline 1 \), a = 0.2883(11), b = 11.3409(12), c = 13.2519(14) Å, α = 69.6950(10)°, β = 73.5850(10)°, γ = 63.8100(10)°, V = 1285.8(2) ų, Z = 2, C₂₈H₂₈CdN₄O₅, M_r = 612.94, D_c = = 1.583 g/cm³, μ = 0.896 mm^–1. In the complex, adjacent dinuclear units [Cd₂(pbmb)₂] are bridged by mip^2– ligands in the μ₂-η², η¹ coordination modes to construct 1D ladder-like chains which are additionally assembled into a 2D supramolecular network via C–H∙∙∙π interactions. Moreover, the luminescence properties of the complex are described.