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Published on: June 16, 2020
Magnetic properties of a mononuclear iron(II) complex with a typical FeN6 coordination octahedron
1Key Laboratory of Optoelectronic Chemical Materials and Devices of the Ministry of Education, Jianghan University, Wuhan, People's Republic of China. yufan0714@163.com
Abstract:
A mononuclear iron(II) complex with the tripodal ligand bis(pyridin-2-ylmethyl)(quinolin-2-ylmethyl)amine (dpqa) has been synthesized and structurally characterized, namely [bis(pyridin-2-ylmethyl)(quinolin-2-ylmethyl)amine-κ(4)N,N',N'',N''']bis(thiocyanato-κS)iron(II), [Fe(NCS)(2)(C(22)H(20)N(4))], exhibits a three-dimensional supramolecular network via π-π interactions and S...H-C hydrogen-bonding interactions between adjacent Fe(II) centres. Temperature-dependent magnetic measurements under different external pressures and X-ray diffraction measurements indicate that all the Fe(II) centres in this complex retain a high-spin state upon cooling from 300 to 2 K. The surprising absence of spin-crossover behaviour for this mononuclear iron(II) complex is attributed to the steric hindrance originating from the substituted quinoline ring in the dpqa ligand.
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