Lanthanide Complexes Assembled from 3-Fluorophthalate and 1,10-Phenanthroline: Syntheses, Crystal Structure, Photoluminescence, and White-Light Emission



Two different crystal forms, [Ln4(Fpht)6(phen)6(H2O)4]·nH2O (Ln = Eu 1, n = 14; Tb 2, n = 12) and [Ln(Fpht)(HFpht)(phen)(H2O)] (Ln = La 3, Eu 4, Tb 5) were obtained from the one-pot reaction of LnIII ions with 3-fluorophthalic acid (H2Fpht) and 1,10-phenanthroline (phen). Complexes 1 and 2 are centrosymmetric tetranuclear molecules with two crystallographically different LnIII ion environments, [Ln(1)O6N2] and [Ln(2)O4N4]. The complexes have a tridentate bridging Fpht ligand and a bidentate terminal Fpht ligand. Complexes 35 show 2D networks with [LnO7N2] polyhedra. There are two kinds of ligands, Fpht and HFpht, which adopt chelating-bridging/monodentate and bidentate-bridging coordination modes, respectively. The LaIII complex shows ligand-centered fluorescence. EuIII and TbIII complexes display red 5D0 → 7F0–4 and green 5D4 → 7F6–2 characteristic luminescence, respectively. Intriguingly, white-light emission was produced when EuIII and TbIII were codoped into the 2D LaIII complex.