Two kinds of 2,4-dichlorobenzoate-based lanthanide coordination polymers tuned by 4,4′-bipyridine: Syntheses, structures, photoluminescence, and magnetism

Two sorts of 2,4-dichlorobenzoate-based lanthanide coordination polymers tuned by 4,4′-bipyridine have been successfully synthesized and structurally characterized. Their photoluminescent and magnetic properties have been investigated. [Display omitted] •Eight 2,4-dichlorobenzoate-based lanthanide coordination polymers tuned by 4,4′-bipyridine are prepared.•The Eu/Tb(III)-containing coordination polymers exhibit the photoluminescent properties.•A Dy(III)-containing coordination polymer shows a slow magnetic relaxation behavior. Ln(NO3)3·nH2O reacted with 2,4-dichlorobenzoic acid (2,4-HDCB) and NaOH under solvothermal conditions of water and ethanol to yield four lanthanide-organic coordination polymers (CPs) [Eu(2,4-DCB)3(CH3CH2OH)2] (1) and [Ln(2,4-DCB)3(H2O)] [Ln = Gd (2), Tb (3), Dy (4)]. The second ligand 4,4′-bipyridine (4,4′-bpy) was introduced into the above reaction systems to provide four new lanthanide-organic CPs [Ln2(2,4-DCB)6(4,4′-bpy)(H2O)2] [Ln = Eu (5), Gd (6), Tb (7), Dy (8)]. Single-crystal and powder X-ray diffraction analyses reveal that CPs 1 and 2 possess similar one-dimensional (1D) structures, and CPs 2–4 and 5–8 are isostructural, respectively. In 1–4, the 2,4-DCB anions bridge the Ln(III) ions to form a 1D chain. In 5–8, six 2,4-DCB anions link two Ln(III) ions into a binuclear Ln2(2,4-DCB)6 unit, and the Ln2(2,4-DCB)6 units are further connected by the 4,4′-bpy co-ligands to generate a 1D chain. The photoluminescent and magnetic properties of 1–8 were investigated.