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Pyrazine-2-amidoxime Ni(II) complexes: from ferromagnetic cluster to antiferromagnetic layer
Guang-Yu An1, Cong-Min Ji, Ai-Li Cui
1Department of Chemistry, Tsinghua University, Beijing, People's Republic of China.
Abstract:
Tetranuclear [Ni(4)(Hpzaox)(2)(pzaox)(2)(py)(4)](ClO(4))(2)·2py (1), [Ni(4)(Hpzaox)(2)(pzaox)(2)(py)(4)](NO(3))(2)·4py (2), and two-dimensional (2D) [Ni(4)(Hpzaox)(2)(pzaox)(2)(H(2)O)(2)](NO(3))(2)·2H(2)O (3) are prepared via the reaction of NiX(2)·6H(2)O and pyrazine-2-amidoxime (H(2)pzaox). All compounds contain [Ni(4)(Hpzaox)(2)(pzaox)(2)](2+) fragments, which assemble to form a tetranuclear or polymeric network. Magnetic studies show that the tetranuclear compounds display usual ferromagnetic coupling via the oxime N-O bridges, and the 2D compound displays unusual antiferromagnetic behavior.
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