Two Gd-2 compounds constructed by 8-hydroxyquinoline Schiff base ligands: Synthesis, structure, and magnetic refrigeration

摘要

Two new Gd-2 compounds having formulae, [Gd-2(hfac)(4)(L1)(2)] (1) and [Gd-2(hfac)(4)(L2)(2)] (2) (hfac = hexafluoroacetylacetonate, HL1 = 2-[4-methylaniline-imino]methy1]-8-hydroxyquinoline and HL2 = 2-[(3,4dimethylaniline)-iminolmethy1]-8-hydroxyquinoline), have been successfully synthesized via applying two different 8-hydroxyquinoline Schiff base ligands, and further characterized by crystallography. Structural analysis shows that both of 1 and 2 are phenoxo-O bridged dinuclear complexes. The magnetic study reveal that 1 and 2 display cryogenic magnetic refrigeration properties with maximum -triangle S-m = 17.66 J kg(-1) K-1 at 2 K and 7 T for 1 and -triangle S-m, = 14.81 J kg(-1) K-1 at 3K and 7 T for 2. (C) 2017 Elsevier B.V. All rights reserved.