Heterometallic Octanuclear Ni(4)(II)Ln(4)(III) (Ln = Y, Gd, Tb, Dy, Ho, Er) Complexes Containing Ni(2)(II)Ln(2)(III)O(4) Distorted Cubane Motifs: Synthesis, Structure, and Magnetic Properties
Metadatos
Afficher la notice complèteAuteur
Kalita, Pankaj; Goura, Joydeb; Herrera Martínez, Juan Manuel; Colacio Rodríguez, Enrique; Chandrasekhar, VadapalliEditorial
American Chemical Society
Date
2018-05-14Referencia bibliográfica
Kalita, P. et. al. Heterometallic Octanuclear Ni(4)(II)Ln(4)(III) (Ln = Y, Gd, Tb, Dy, Ho, Er) Complexes Containing Ni(2)(II)Ln(2)(III)O(4) Distorted Cubane Motifs: Synthesis, Structure, and Magnetic Properties. ACS Omega 2018, 3, 5202−5211 [http://dx.doi.org/10.1021/acsomega.8b00292]
Patrocinador
Ministerio de Economía y Competitividad (MINECO) and EU Feder Funds (Project CTQ2014-56312-P), the Junta de Andalucía (FQM-195 and the Project of Excellence P11-FQM- 7756), and the University of Granada for financial support.Résumé
The reaction of 2-methoxy-6-[{2-(2-hydroxyethylamino)ethylimino}methyl] phenol (LH3) with lanthanide metal
salts followed by the addition of nickel acetate allowed isolation of a family of octanuclear complexes, [Ni4Ln4(μ2-OH)2(μ3-
OH)4(μ-OOCCH3)8(LH2)4]·(OH)2·xH2O. Single crystal X-ray diffraction studies of these complexes reveal that their central
metallic core consists of two tetranuclear [Ni2Ln2O4] cubane subunits fused together by acetate and hydroxide bridges. The
magnetic study of these complexes reveals a ferromagnetic interaction between the LnIII and the NiII center. The magnitude of
exchange coupling between the NiII and LnIII center, parametrized from the magnetic data of the Gd analogue, gives J = +0.86
cm−1. The magneto caloric effect, studied for the NiII 4GdIII 4 complex, shows a maximum of magnetic entropy change, −ΔSm =
22.58 J kg−1 K−1 at 3 K for an applied external field of 5 T.