在一个由Co (II) 离子和奇拉三元基Bis (氧化物) 基组成的基于分子的磁铁中, induced-field诱导的铁磁状态
Youhei Numata1, Katsuya Inoue, Nikolai Baranov
1Department of Structural Molecular Science, The Graduate University for Advanced Studies, Okazaki 444-8585, Japan.
Journal of the American Chemical Society
|July 31, 2007
概括
这项研究引入了一种新的基于分子的磁铁,[Co(hfac) 2).BNO*,表现出四种不同的磁性状态. 它的状结构导致了独特的磁性,包括在低温下硬磁阶段.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 磁力学 磁力学 是一种
背景情况:
- 基于分子的磁铁提供可调节的特性.
- 状结构可以影响磁性排序.
- 科巴尔特复合物被探索用于磁性应用.
研究的目的:
- 合成和描述一种新的基于分子的磁铁,[Co(hfac) 2].BNO*.
- 研究晶体结构和磁性特性.
- 确定其磁态的温度和磁场依赖性.
主要方法:
- 单晶X射线衍射用于结构分析.
- 取决于温度的磁感应度测量.
- 同热磁化曲线在各种温度和场.
主要成果:
- 在非中心对称的P1空间组中形成奇拉单维链.
- 对四种磁性基态的观察:偏磁性,反铁磁性,强制铁磁性和场诱导的转移性铁磁性.
- 一个硬磁铁的表现行为与强制场的25kOe在2K.
结论:
- 的双氧化连接体在复合体中诱导独特的磁性特性.
- 该材料表现出由温度和磁场驱动的复杂磁相转换.
- 离子的Ising特性稳定了转移稳定的铁磁状态,从而产生了硬磁铁的特性.
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