Lanthanide(III) Hexanuclear Circular Helicates: Slow Magnetic Relaxation, Toroidal Arrangement of Magnetic Moments, and Magnetocaloric Effects

Jingjing Lu (1, 2) , Vincent Montigaud (3) , Olivier Cador (3) , Jianfeng Wu (2) , Lang Zhao (2) , Xiao-Lei Li (2) , Mei Guo (2) , Boris Le Guennic (3) , Jinkui Tang (1, 2)

1 USTB - University of Science and Technology Beijing [Beijing]
2 CAS - Chinese Academy of Sciences [Beijing]
3 ISCR - Institut des Sciences Chimiques de Rennes

Four hexanuclear circular helicates, {[DyL(DMF)]·6CFSO·12DMF} (), {[GdL(DMF)]·6CFSO·12DMF} (), [DyL(DMF)(HO)]·6ClO·4HO·10DMF (), and [GdL(DMF)]·6ClO·2HO·10DMF (), where DMF = ,-dimethylformamide, were synthesized by employing a glutaratedihydrazide-bridged bis(3-methoxysalicylaldehyde) ligand (HL) and characterized structurally and magnetically. Direct-current magnetic susceptibility studies indicated predominant weak antiferromagnetic exchange interactions among gadolinium analogues, which were quantified using the software, giving = -0.003 cm with = 2.00 for and = -0.001 cm with = 2.02 for . Alternating-current magnetic susceptibility measurements indicated that complexes and show slow relaxation of magnetization behavior, further supported by theoretical calculations that also highlighted the toroidal arrangement of the magnetic moments.

Domains: Chemical Sciences

Jingjing Lu, Vincent Montigaud, Olivier Cador, Jianfeng Wu, Lang Zhao, et al.. Lanthanide(III) Hexanuclear Circular Helicates: Slow Magnetic Relaxation, Toroidal Arrangement of Magnetic Moments, and Magnetocaloric Effects. Inorganic Chemistry, 2019, 58 (18), pp.11903-11911. ⟨10.1021/acs.inorgchem.9b01068⟩. ⟨hal-02179644⟩