Slow Magnetic Relaxation and Luminescence Properties in Tetra β-Diketonate Lanthanide(III) Complexes

The reaction of [Ln(btfa)3(H2O)2] (btfa- = 4,4,4-trifluoro-1-phenyl-1,3-butanedionate) with additional 4,4,4-trifluoro-1-phenyl-1,3-butanedione (Hbtfa) and acridine (Acr) in ethanol allows the isolation mononuclear compounds HAcr[Nd(btfa)4]·EtOH, (1) HAcr[Ln(btfa)4], Ln Dy (2) Yb (3); HAcr+ acridinium cation. Magnetic measurements indicate that complexes 1–3 show field-induced single-ion magnet behavior anisotropy energy barriers preexponential factors Ueff 20.7 cm−1, τ0 24.5 × 10−8 s; 40.5 8.6 10−10 s 22.7 8.4 s, for respectively. solid-state luminescence emission NIR region shows efficient transfer from 4,4,4-trifluoro-1-phenyl-1,3-butanedionate ligands to central Ln3+ ion case 1 3.