Hydrothermal syntheses, crystal structures and properties of lanthanide complexes with 4-Hydroxy-6-methylnicotinic acid

Four isomorphous lanthanide complexes, [Ln(2)(L)(6)(H2O)(2)]center dot 2H(2)O [Ln = Ce (1), Ln = Nd (2), Ln = Sm (3), Ln = Pr (4)] (HL = 4-Hydroxy-6-methylnicotinic acid) were synthesized by the reaction of nitrate salts of Ln(III) and HL by hydrothermal method, which were characterized by single-crystal X-ray diffraction. elemental analysis, FT-IR spectra, UV-vis spectra, TG analyses and X-ray powder diffraction (XRPD). The crystal structures of 1-4 consist of homodinuclear species, which bridged by two oxygen atoms from two L ligands. The photoluminescence properties of compounds 3 and 4 in the solid state at room temperature were investigated. The complex 3 is demonstrated orange-red luminescence, while the luminescence spectrum of complex 4 is typical for the praseodymium complexes. (C) 2012 Elsevier B.V. All rights reserved.