Field-induced slow magnetic relaxation in a distorted trigonal prismatic cobalt(II) complex

• Published in: Inorganic chemistry communications 2024-07, Vol.165, p.112551, Article 112551
• Main Authors: Zeng, Meng-Meng, Ruan, Ze-Yu, Deng, Wei, Wu, Si-Guo, Tong, Ming-Liang
• Format: Article
• Language: English
• Subjects: cobalt(II); Single-ion magnet; Slow magnetic relaxation
• ISSN: 1387-7003; 1879-0259
• DOI: 10.1016/j.inoche.2024.112551

Field-induced slow magnetic relaxation is observed in a distorted trigonal prismatic cobalt(II) complex enforced by a helical pentadentate ligand. [Display omitted] •Two mononuclear complexes with distorted trigonal prismatic geometry were synthesized by employing a helical pentadentate ligand.•Magnetic measurements and ab initio calculations indicate easy axis anisotropy and field-induced slow magnetic relaxation in Co(II) complex. Two mononuclear complexes [M(DQ)(OTf)](OTf)·H2O (M = Co for 1 and Fe for 2, DQ = 6,6′′-di(quinolin-8-yl)-4′-phenyl-2,2′:6′,2′′-terpyridine) with distorted trigonal prismatic geometry have been synthesized and characterized. Crystal structures show that the 3d ions are helically coordinated by a pentadentate DQ and encapsulated by a terminal OTf− anion, resulting in [MN5O] coordination environments. Magnetic measurements and ab initio calculation indicate that complex 1 displays easy axis anisotropy and exhibits field-induced slow magnetic relaxation which is dominated by Raman and direct processes. For 2, no slow magnetic relaxation had been recorded owing to the significant fast quantum tunneling of magnetization.