A family of three-dimensional 3d–4f and 4d–4f heterometallic coordination polymers based on mixed isonicotinate and 2-sulfobenzoate ligands: syntheses, structures and photoluminescent properties?

Dalton Transactions Pub Date: 2012-03-08 DOI: 10.1039/C2DT30268C

Abstract

Hydrothermal reactions of isonicotinic acid (Hina), 2-sulfobenzoic acid (H2sba), d-block metal salts and lanthanide oxides/hydroxides yielded 17 three-dimensional (3D) 3d–4f and 4d–4f heterometallic coordination polymers (HCPs). They are formulated as [LaAg(sba)(ina)2]n (1), [Ln2Ag2(sba)2(ina)4(H2O)2]n [Ln = Pr (2), Nd (3), Sm (4), Eu (5), Gd (6), Tb (7), Dy (8), Ho (9), Er (10)] and [Ln2Cu2(sba)2(ina)4(H2O)2]n [Ln = La (11), Pr (12), Nd (13), Sm (14), Eu (15), Gd (16), Tb (17)]. Their structures were characterized by single crystal X-ray diffraction, powder X-ray diffraction (XRD), infrared (IR) spectroscopy, elemental analysis (EA), and thermogravimetric analysis (TGA). It reveals that they represent two structural types of 3D HCPs. Furthermore, the investigations of their solid-state photoluminescent (PL) property demonstrate the extraordinary emission behaviors. HCP 1(La–Ag) exhibits tunable blue-to-green PL emissions by variation of excitation light. HCPs 6(Gd–Ag), 11(La–Cu), 12(Pr–Cu) and 16(Gd–Cu) show d10-metal-based ligand-to-metal charge transfer (LMCT) or metal-to-ligand charge transfer (MLCT) emissions. HCPs 3(Nd–Ag), 4(Sm–Ag), 5(Eu–Ag), 7(Tb–Ag), 8(Dy–Ag), 13(Nd–Cu), 14(Sm–Cu), 15(Eu–Cu) and 17(Tb–Cu) display characteristic PL emissions of the corresponding Ln(III) ions, while both d10-metal-based and 4f-metal-centered emissions are observed in the emission spectra of 4(Sm–Ag), 8(Dy–Ag), 14(Sm–Cu) and 17(Tb–Cu).

Graphical abstract: A family of three-dimensional 3d–4f and 4d–4f heterometallic coordination polymers based on mixed isonicotinate and 2-sulfobenzoate ligands: syntheses, structures and photoluminescent properties
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