一个N2(3-) 基结桥接的合物复合物,在14K时呈现磁性歇斯底里
Jeffrey D Rinehart1, Ming Fang, William J Evans
1Department of Chemistry, University of California, Berkeley, California 94720, USA.
Journal of the American Chemical Society
|August 16, 2011
概括
研究人员合成了新的迪兰化物复合物,表现出单分子磁铁行为. 复合体是迄今为止最硬的分子磁体,它展示了有效的磁交换合,以实现更广泛的温度放松.
科学领域:
- 协调化学 协调化学
- 磁电化学 磁电化学 磁电化学
- 材料科学 材料科学 材料科学
背景情况:
- 单分子磁铁 (SMM) 对于开发高密度数据存储和量子计算至关重要.
- 兰化离子具有强烈的磁性异构性,这是SMM的关键性质.
- (N(2)(3-)) 基桥可以调解金属中心之间的磁交换相互作用.
研究的目的:
- 为了合成和表征新的N(2)(3-) 基因桥接的迪兰化物复合物.
- 研究这些新复合物的磁性特性,特别是SMM行为.
- 探索N(2)(3-) 基桥在调解磁交换和提高SMM性能方面的作用.
主要方法:
- 三种迪兰化物复合物的合成:{[(Me(3) Si) (((2) N](2) ((THF) Ln}(2) ((μ-η(2):η(2) -N(2)) (((-) (Ln = Tb, Ho, Er).
- 测量磁性特性,包括磁性敏感性和磁性歇斯底里.
- 与非根基桥接的类似物进行比较,以阐明根基桥的效果.
主要成果:
- 这三种合成的迪兰化物复合体都表现出单分子磁铁行为特征.
- (Tb) 同源在14K时显示磁性歇斯底里,阻塞温度为13.9K (100秒).
- 该N(2)(3-) 基桥有效地调解磁交换合,阻碍零场放松并扩大操作温度范围.
结论:
- 结合Tb(III) 异质性和N(2)(3-) 基交换合的协同作用组合,产生了迄今为止报告的最硬的分子磁铁.
- 基桥对于在较高温度下实现强大的慢磁放松至关重要.
- 这些发现为设计具有更高性能的先进分子磁性材料铺平了道路.
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