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Published on: August 20, 2014
像梯子一样的铁磁旋转合网络在一个pi-结合的吊多基基上
Takashi Kaneko1, Takahisa Makino, Hiroshi Miyaji
1Department of Chemistry and Chemical Engineering, Faculty of Engineering, Niigata University, Ikarashi 2-8050, Niigata 950-2181, Japan. kanetaka@gs.niigata-u.ac.jp
Journal of the American Chemical Society
|March 20, 2003
概括
研究人员合成了一种具有稳定基的新型多基基,实现了高自旋量子数. 这表明在pi结合聚合物中存在一个强大的铁磁自旋网络,能够抵御缺陷.
科学领域:
- 有机化学 有机化学
- 聚合物科学 聚合物科学
- 材料科学 材料科学 材料科学
背景情况:
- 新型有机基聚合物的开发对于先进的电子和磁性应用至关重要.
- 稳定的基激素为材料设计提供独特的自旋特性.
研究的目的:
- 合成和表征一种新的基于多 (9,10-乙烯乙烯) 的多基基,具有悬挂基.
- 为了研究合成的多根基的磁性特性和自旋合行为.
主要方法:
- 使用Palladium(0) 催化剂的甲基兰特拉单体的聚合.
- 从基前体聚合物中制备聚基基.
- 电子自旋共振 (ESR) 光谱分析自旋密度分布.
- SQUID磁力测量仪用于测量磁化和磁性易感性.
主要成果:
- 成功合成了一种具有平均分子量为5 x 10^3.3的可溶性多基.
- 多基基在室温下表现出稳定性.
- 据ESR数据显示,在烯骨干上,自旋密度的有效移位.
- 测量结果显示了很大的平均旋转量子数 (S = 5/2),这意味着大量的铁磁旋转合.
结论:
- 合成的多基基具有铁磁自旋合网络,该网络延伸到整个pi-conjugated链.
- 该材料对旋转缺陷表现出相当大的不敏感性,这表明它有可能用于强大的磁性应用.
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