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

• Published in: Magnetochemistry 2023-05, Vol.9 (5), p.131
• Main Authors: Speed, Saskia, Tubau, Ànnia, Vicente, Ramon, Castro, Eva, Font-Bardia, Mercè
• Format: Article
• Language: English
• Subjects: Analysis; Anisotropy; beta-diketonate anion; Chemical synthesis; Coordination compounds; Diffraction; dysprosium(III); Energy transfer; Ethanol; Identification and classification; Ketones; Ligands; Luminescence; Magnetic induction; Magnetic measurement; Magnetic properties; Magnetic relaxation; Methods; neodymium(III); Optical properties; Radiation; Sensors; Single crystals; SMMs; Spectrum analysis; X-rays; ytterbium(III)
• ISSN: 2312-7481; 2312-7481
• DOI: 10.3390/magnetochemistry9050131

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