Terbium(III) and Yttrium(III) Complexes with Pyridine-Substituted Nitronyl Nitroxide Radical and Different β-Diketonate Ligands. Crystal Structures and Magnetic and Luminescence Properties
Citations Over TimeTop 11% of 2014 papers
Abstract
A terbium(III) complex of nitronyl nitroxide free radical 2-(2-pyridyl)-4,4,5,5-tetramethyl-4,5-dihydro1H-imidazolyl-1-oxy-3-oxide (NIT2Py), [Tb(acac)3NIT2Py]·0.5H2O (3) (acac = acetylacetonate), was synthesized for comparison with the previously reported [Tb(hfac)3NIT2Py]·0.5C7H16 (1) (hfac = hexafluoroacetylacetonate), together with their yttrium analogues [Y(hfac)3NIT2Py]·0.5C7H16 (2) and [Y(acac)3NIT2Py]·0.5H2O (4). The crystal structures show that in all complexes the nitronyl nitroxide radical acts as a chelating ligand. Magnetic studies show that 3 like 1 exhibits slow relaxation of magnetization at low temperature, suggesting single-molecule magnet behavior. The luminescence spectra show resolved vibronic structure with the main interval decreasing from 1600 cm(-1) to 1400 cm(-1) between 80 and 300 K. This effect is analyzed quantitatively using experimental Raman frequencies.
Related Papers
- → Electron paramagnetic resonance spectra of the tert-butylperoxy and tert-butoxy adducts to phenyl tert-butyl nitrone and 2-methyl-2-nitrosopropane. Oxygen-17 hyperfine coupling constants(1978)48 cited
- → The use of fluorophore‐containing spin traps as potential probes to localize free radicals in cells with fluorescence imaging methods(1995)23 cited
- → Spectrofluorimetric determination of trace amounts of Tb(III) using acetylacetone in ethanol solution(1988)9 cited
- → Facile formation of luminescent terbium(III) aryloxide complexes directly from terbium metal including the X-ray crystal structures of Tb(OC6H3Me2-2,6)3(THF)3 and Tb(OC6H3iPr2-2,6)3(THF)2(2001)7 cited
- → ChemInform Abstract: Nitroxides (Aminyl Oxides). Part 40. ESR Spectroscopic Studies of β‐Sulfonyl Substituted Vinyl Nitroxides and of a Vinylogous Nitronyl Nitroxide.(1990)