Syntheses and magnetic properties of a series of discrete Ni(II)-Ln(III) heterometallic complexes based on 2,3-dichlorobenzoate and 2,2′-bipyridine

Abstract

Herein, a series of zero-dimensional (0D) heterometallic complexes, [Ln2Ni2(2,3-DCB)10(2,2′-bpy)2] [Ln = Nd (1), Sm (2), Eu (3), Gd (4), Tb (5), Dy (6), Er (7) and Yb (8)], were obtained by the reactions of Ln(NO3)3·nH2O, Ni(NO3)2·6H2O, 2,3-dichlorobenzoic acid (2,3-HDCB), NaOH and 2,2′-bipyridine (2,2′-bpy) under solvothermal conditions. The structures of complexes 1–8 were determined by single-crystal X-ray diffraction and further characterized by elemental analysis, FT-IR, PXRD and TGA. Complexes 1–8 are isostructural, and display discrete linear tetranuclear cluster structures constructed from ten 2,3-DCB anions linking two Ln(III) and two Ni(II) ions by four types of coordination modes. Such linear tetranuclear molecules can be extended into a two-dimensional (2D) supramolecular network through π–π interactions between 2,3-DCB and 2,2′-bpy. The magnetic properties of complexes 1–8 were also studied.