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(II) 基磁铁或 (V) 基磁铁含有非协调的芳香分子
Toshinori Kashiwagi1, Shin-Ichi Ohkoshi, Hidetake Seino
1Research Center for Advanced Science and Technology, The University of Tokyo, Meguro-ku, Japan.
Journal of the American Chemical Society
|April 22, 2004
概括
研究人员合成了一种新型的支柱状层磁性材料,[{MnII{pyrimidine}{H2O}}2{MnII{H2O}2}{WV{CN}8}2]{pyrimidine}2.2H2O,在47K时呈现磁性相变.这种材料显示了和离子之间的反铁磁相互作用.
科学领域:
- 材料科学 材料科学 材料科学
- 无机化学 无机化学
- 磁力学 磁力学 是一种
背景情况:
- 柱状层磁性材料由于其独特的结构和磁性特性而引起人们的兴趣.
- 将非协调的分子纳入这些框架可以影响它们的维度和功能.
研究的目的:
- 为了合成和表征一种新的支柱状层磁性材料,其中含有非协调的芳香分子.
- 为了研究合成化合物的磁性特性和相变.
主要方法:
- 化学合成的化合物[{MnII(pyrimidine) ((H2O) }2{MnII ((H2O) 2}{WV ((CN) 8}2{pyrimidine) 2.2H2O.}2{MnII ((H2O) 2}{WV ((CN) 8}2}{pyrimidine) 2.2H2O.}2{MnII (pyrimidine) 2}{MnII (pyrimidine) 2}{MnII (pyrimidine) 2}2{MnII (pyrimidine) 2}2{MnII (pyrimidine) 2}2{MnII (pyrimidine) 2}2}2{MnII (pyrimidine) 2}2}2{MnII (pyrimidine) 2}2}2{MnII (pyrimidine) 2}2}2{MnII (pyrimidine) 2}2}2}2{MnII (pyrimidine) 2}2}2}2}2}2}2{MnII (pyrimidine) 2}2}2}3
- 使用X射线衍射进行表征,以确定结构特征,包括一维通道.
- 测量磁性特性,包括磁化与温度和外部磁场对比,以及磁性歇斯底里循环.
主要成果:
- 合成材料具有一维通道 (6.2 x 2.1 Å),由非协调的金胺分子占据.
- 观察到磁相过渡温度 (TC) 为47K.
- 在2K时13.0μB的和磁化 (MS) 表明MnII (S = 5/2) 和WV (S = 1/2) 离子之间的反铁磁相互作用.
- 在2K时测量了17G的强制场 (HC).
结论:
- 一个支柱状层磁性材料的成功合成,具有可访问的通道.
- 该材料表现出特有的磁性行为,包括相位过渡和反铁磁合.
- 这些发现有助于理解磁协调化合物中的结构属性关系.
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