三维化物桥梁双金属磁铁的压力反应
Masaaki Ohba1, Wakako Kaneko, Susumu Kitagawa
1Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan. ohba@sbchem.kyoto-u.ac.jp
Journal of the American Chemical Society
|March 12, 2008
概括
压力显著改变了化物桥接协调聚合物的磁性. 这些材料在水静压下显示磁相和过渡温度的可逆和不可逆变化,揭示了框架强度和磁结构的洞察力.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 磁力学 磁力学 是一种
背景情况:
- 化物桥接双金属协调聚合物是一种具有可调节磁性质的材料.
- 了解这些材料对压力等外部刺激的反应对于它们在先进技术中的应用至关重要.
研究的目的:
- 为了研究水静压对三种不同的3D化物桥梁双金属协调聚合物磁体结构和磁性特性的影响.
- 为了将压力引起的变化与这些材料固有的磁性结构和框架稳定性相关联.
主要方法:
- 系统地应用高达19.8GPa的液压压力,使用活塞气和钻石细胞.
- 在不同压力条件下的结构和磁性相变的表征.
- 分析磁性特性,包括过渡温度 (TC) 和磁化.
主要成果:
- 铁磁[Mn(en) ]3[Cr(CN) [6]2.4H2O (1) 呈现出可逆的晶体到形态相位过渡,TC在4.7GPa时从69K增加到126K,并且在更高的压力下抑制磁化.
- 铁磁[Ni(dipn) ]3[Cr(CN) [6]2.3H2O (2) 显示了可逆的铁磁到类磁相位转换高达4.7 GPa,同时保持了结晶性.
- 多孔铁磁铁[Ni () 滴) ]2[Ni () 滴 (H2O) ][Fe (CN) ]2.11H2O (3) 容易无形化并不可逆转地失去其铁磁相,低于1.0 GPa.
结论:
- 灵活的化物桥梁磁框架显示显著的压力灵敏度,反映其磁结构和框架强度的变化.
- 观察到的压力诱导的转变为这些协调聚合物的机械和磁性行为提供了GPa尺度的理解.
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