Structural and Magnetic Properties of Layered Copper(II) Coordination Polymers Intercalating s and f Metal Ions

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• 作者：Jorge A. R. Navarro ; Elisa Barea ; Juan M. Salas ; Norberto Masciocchi ; Simona Galli ; Angelo Sironi
• 刊名：Inorganic Chemistry
• 出版年：2007
• 出版时间：April 16, 2007
• 年：2007
• 卷：46
• 期：8
• 页码：2988 - 2997
• 全文大小：555K
• 年卷期：v.46,no.8(April 16, 2007)
• ISSN：1520-510X

文摘

The nanoporous coordination polymer [Cu(pyrimidin-2-olate-N1,N3)₂]_n (1_C) of the sodalite zeotype sorbs a varietyof metal nitrates [M(NO₃)_m, M = Na⁺, K⁺, Rb⁺, Tl⁺, Ca²⁺, Sr²⁺, Ba²⁺, Pb²⁺, La³⁺, Nd³⁺, Gd³⁺, Er³⁺] from H₂O/MeOHsolutions, with a concomitant structural change to a layered [Cu(pyrimidin-2-olate-N1,N3)₂]_n·[M(NO₃)_m]_n/2 (MNO₃@1_L)coordination framework. Single-crystal X-ray diffraction analyses revealed that the layers are based on Cu₄(pyrimidin-2-olate-N1,N3)₄ square grids of copper(II) ions bridged by N1,N3 exobidentate ligands, displaying a structural motifof the metallacalix[4]arene type in pinched cone conformation. The interlayer space is occupied by the guest metalnitrates, each metal being coordinated by (at least) the four oxygen atoms of a metallacalix[4]arene. Magneticmeasurements on the MNO₃@1_L series denoted a weak ferromagnetic ordering taking place below the Néeltemperatures (typically close to 35 K), arising from spin-canting phenomena of the antiferromagnetically coupledcopper centers. When M = Nd³⁺, Gd³⁺, or Er³⁺, additional magnetic ordering is observed at lower temperatures,which, on the basis of static and dynamic magnetic susceptibility measurements, can be attributed to copper-lanthanide interactions.