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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Dodecanuclear [Cu(II)6Gd(III)6] nanoclusters as magnetic refrigerants
Alina S Dinca1, Alberto Ghirri, Augustin M Madalan
1Inorganic Chemistry Laboratory, Faculty of Chemistry, University of Bucharest, Str. Dumbrava Rosie nr. 23, 020464 Bucharest, Romania.
Abstract:
A novel dodecanuclear complex, [{(HL)(L)(DMF)Cu(II)Gd(III)(DMF)(H(2)O)}(6)]·6DMF (1; DMF = N,N-dimethylformamide), has been obtained using the ligand resulting from the condensation of 3-formylsalicylic acid with hydroxylamine (H(3)L). The exchange interaction between the phenoxo-bridged Cu(II) and Gd(III) ions is weak ferromagnetic (J = +1.01 cm(-1)). The combination of a high-spin ground state with small anisotropy leads to a significant magnetocaloric effect [-ΔS(m)(0-7 T) = 23.5 J K g(-1) K(-1) at ∼2 K].
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