A ferromagnetic tetranuclear nickel(II) Schiff-base complex with an asymmetric Ni4O4 cubane core

The ferromagnetic tetranuclear nickel(II) complex [Ni4(L)4(CH3OH)2]·2MeOH·8H2O (1) has been synthesized by reacting nickel nitrate hexahydrate with the Schiff base ligand H2L (H2L = N-(2-hydroxyphenyl)-3-methoxy-salicylideneamine). Complex 1 was characterized by analytical, thermogravimetric, optical and magnetic techniques. The solid state structure of 1 was established by single crystal X-ray diffraction analysis. Crystal structure determination shows the formation of a distorted Ni4O4 cubane moiety encapsulated by four Schiff base ligands. Compound 1 crystallizes in the triclinic space group P1¯ with a = 12.7624(9) Å, b = 15.0477(9) Å, c = 16.8589(10) Å, α = 94.732(2)°, β = 94.308(2)°, γ = 99.136(2)° and Z = 2. The magnetic properties of complex 1 show a predominant ferromagnetic coupling inside the Ni4 cluster with g = 2.240, J1 = +0.88 cm−1, J2 = +0.84 cm−1, J3 = −0.014 cm−1, J4 = +1.22 cm−1 and D = 9.6 cm−1.

A ferromagnetic tetranuclear nickel(II) complex [Ni4(L)4(CH3OH)2]·2MeOH·8H2O (1) has been synthesized and characterized. The solid-state structure of 1 shows a distorted asymmetric Ni4O4 cubane moiety encapsulated by Schiff base ligands. The magnetic study of 1 showed predominant ferromagnetic coupling within the Ni4O4 cluster.Figure optionsDownload as PowerPoint slide