HAL will be down for maintenance from Friday, June 10 at 4pm through Monday, June 13 at 9am. More information
Skip to Main content Skip to Navigation
Journal articles

Field-induced single ion magnet behaviour of discrete and one-dimensional complexes containing [bis(1-methylimidazol-2-yl)ketone]-cobalt( ii ) building units

Abstract : We describe herein the first examples of six-coordinate CoII single-ion magnets (SIMs) based on the β-diimine Mebik ligand [Mebik = bis(1-methylimidazol-2-yl)ketone]: two mononuclear [CoII(Rbik)2L2] complexes and one mixed-valence {CoIII2CoII}n chain of formulas [CoII(Mebik)(H2O)(dmso)(μ-NC)2CoIII2(μ-2,5-dpp)(CN)6]n·1.4nH2O (3) [L = NCS (1), NCSe (2) and 2,5-dpp = 2,5-bis(2-pyridyl)pyrazine (3)]. Two bidentate Mebik molecules plus two monodentate N-coordinated pseudohalide groups in cis positions build somewhat distorted octahedral surroundings around the high-spin cobalt(II) ions in 1 and 2. The diamagnetic [CoIII2(μ-2,5-dpp)(CN)8]2− metalloligand coordinates the paramagnetic [CoII(Mebik)(H2O)(dmso)]2+ complex cations in a bis-monodentate fashion to afford neutral zigzag heterobimetallic chains in 3. Ab initio calculations, and cryomagnetic dc (2.0–300 K) and ac (2.0–12 K) measurements as well as EPR spectroscopy for 1–3 show the existence of magnetically isolated high-spin cobalt(II) ions with D values of 59.84–89.90 (1), 66.32–93.90 (2) and 70.40–127.20 cm−1 (3) and field-induced slow relaxation of the magnetization, being thus new examples of SIMs with transversal magnetic anisotropy. The analysis of their relaxation dynamics reveals that the relaxation of the magnetization occurs by the Raman (with values of the n parameter covering the range 6.0–6.8) and direct spin-phonon processes.
Document type :
Journal articles
Complete list of metadata

Contributor : Hal Sorbonne Université Gestionnaire Connect in order to contact the contributor
Submitted on : Tuesday, November 9, 2021 - 10:36:55 AM
Last modification on : Friday, April 1, 2022 - 3:47:16 AM
Long-term archiving on: : Thursday, February 10, 2022 - 6:27:27 PM


Jiménez et al. - 2021 - Field...
Files produced by the author(s)



Juan-Ramón Jiménez, Buqing Xu, Hasnaa El Said, Yanling Li, Jurgen von Bardeleben, et al.. Field-induced single ion magnet behaviour of discrete and one-dimensional complexes containing [bis(1-methylimidazol-2-yl)ketone]-cobalt( ii ) building units. Dalton Transactions, Royal Society of Chemistry, 2021, ⟨10.1039/d1dt02441h⟩. ⟨hal-03420373⟩



Record views


Files downloads