NIR luminescence of 2-(2,2,2-trifluoroethyl)-1-indone (TFI) neodymium and ytterbium complexes

Two series of six β-diketone, 2-(2,2,2-trifluoroethyl)-1-indone (TFI) containing a trifluorinated alkyl group and a rigid indone group, neodymium and ytterbium complexes, namely, [Ln(TFI)3L] [Ln=Nd; L=(H2O)2 (1), bpy (2) and phen (3); Ln=Yb; L=(H2O)2 (4), bpy (5) and phen (6); bpy=2,2-bipyridine, phen=1,10-phenanthroline], have been synthesized and isolated. X-ray crystallographic analysis reveals that complex 2 is mononuclear structure in which the central Nd3+ ion is eight-coordinated by six oxygen atoms furnished by three TFI ligands and two nitrogen atoms from ancillary ligand. PXRD analysis suggests that all complexes 1 and 4, 2 and 5, 3 and 6 are isomorphic, respectively The room-temperature PL spectra of complexes 1-6 show strong characteristic NIR luminescence of the corresponding Nd3+ and Yb3+ ions and the substitution of the solvent molecules by bidentate nitrogen ligands essentially enhance the NIR luminescence quantum yields and lifetimes of the complexes.