Binary metal(II)–pyromellitate coordination polymers, M₂(pm) (M=Co, Fe, Mn): synthesis, structures and magnetic properties

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• 作者：Kumagai ; Hitoshi ; Chapman ; Karena W. ; Kepert ; Cameron J. ; Kurmoo ; Mohamedally
• 关键词：Carboxylate ; Cobalt ; Iron ; Magnetism ; Manganese ; Pyromellitate ; Framework
• 刊名：Polyhedron
• 出版年：2003
• 出版时间：July 15, 2003
• 年：2003
• 卷：22
• 期：14-17
• 页码：1921-1927
• 全文大小：409 K

文摘

The hydrothermal synthesis, structures and magnetic properties of the isostructural coordination polymers _∞³[M₂^II(pm)], M=Co, Fe or Mn and pm=pyromellitate, 1,2,4,5-benzenetetracarboxylate, are described. The structure consists of 1D chains of edge-sharing MO₆ octahedra that are connected into layers via OCO bridges. The layers are held together by the pyromellitate (pm⁴⁻) backbone to give a 3D structure where each ligand participates in an unprecedented 12 coordination MO bonds to ten metal atoms. The Fe and Mn analogues are antiferromagnets whereas the Co compound displays a more complex behaviour, existing in one of three magnetic ground states at low temperature (collinear antiferromagnetism, canted antiferromagnetism and field induced ferromagnetism).