Syntheses, crystal structures, visible and near-IR luminescent properties of ternary lanthanide (Dy3+, Tm3+) complexes containing 4,4,4-trifluoro-1-phenyl-1,3-butanedione and 1,10-phenanthroline

The ligands 4,4,4-trifluoro-1-phenyl-1,3-butanedione (Hbfa) and 1,10-phenanthroline (phen) were used to prepare ternary lanthanide (Ln) complexes [Dy(bfa)3phen and Tm(bfa)3phen]. Crystal data: Dy(bfa)3phen C42H26F9N2O6Dy, triclinic, P1¯, a=9.9450(6) Å, b=14.0944(9) Å, c=14.6043(9) Å, α=82.104(1)°, β=87.006(1)°, γ=76.490(1)°, V=1971.1(2) Å3, Z=2; Tm(bfa)3phen C42H26F9N2O6Tm, triclinic, P1¯, a=9.898(5) Å, b=13.918(5) Å, c=14.753(5) Å, α=83.517(5)°, β=86.899(5)°, γ=76.818(5)°, V=1965.3(14) Å3, Z=2. The coordination number of the central Ln3+ (Ln=Dy, Tm) ion is eight, with six oxygen atoms from three Hbfa ligands and two nitrogen atoms from the phen ligand. The photophysical properties of the two complexes were studied by absorption spectra, diffuse reflectance spectra, and emission spectra. They show the characteristic luminescence of the corresponding Ln3+ ion in both visible and near-IR (NIR) region. Additionally, the energy transfer mechanisms between the ligands and central Ln3+ ions were discussed.