Structures and magnetic properties of two dinuclear lanthanide complexes based on 8-hydroxyquinoline Schiff base derivatives

Based on 8-hydroxyquinoline Schiff base derivative and auxiliary ligand beta-diketonate, two new dinuclear lanthanide complexes [Gd-2(L1)(2)(bfac)(4)] ( 1 ) and [Dy-2(L2)(2)(acac)(2)(CH3OH)2]center dot CH3OH (2) (HL1 = 2[((4-phenethyl)- imino)methyl]-8-hydroxyquinoline, H(2)L2 = 2-[((4-methyl)-2-(arboxyl)-imino)]methyl]-8hydroxyquinoline, Hbfac = hexafluoroacetylacetonate, Hacac = acetylacetonate,) were successfully isolated and characterized. Structural analysis reveal that complexes 1 and 2 both contain a binuclear Ln2 cluster, in which two eight-coordinated Ln(III) ions are located in distorted dodecahedral geometry and bridged by phenoxide oxygen atom. In addition, their magnetic properties are investigated in detail. The results suggest that ferromagnetic interactions between adjacent Gd3+ ions can be observed in 1 , which exhibits remarkable magnetic refrigeration properties with -Delta S-max = 17.74 J kg(-1) K-1 (T = 2.0 K and Delta H = 7.0 T). Complex 2 displays slow magnetic relaxation behaviors with Delta E/k(B) approximate to 2.16 K and tau(0) approximate to 1.38 x 10(-5) s. (C) 2021 Elsevier B.V. All rights reserved.