在三角 prismatic (((III) 复合体中缓慢的磁放松
Jeffrey D Rinehart1, Jeffrey R Long
1Department of Chemistry, University of California, Berkeley, California 94720-1460, USA.
Journal of the American Chemical Society
|August 20, 2009
概括
这项研究揭示了复合物的缓慢磁性放松,U(Ph(2) BPz(2)) ((3),表明了单分子磁体应用的潜力. 在较低的温度下观察到量子道,这表明了基磁体的新设计策略.
科学领域:
- * 无机化学 无机化学
- * 材料科学 材料科学
- * * 量子物理 量子物理
背景情况:
- *单分子磁铁 (SMM) 对于开发先进的磁性材料至关重要.
- *由于其独特的电子特性,复合物是SMM的有希望的候选物.
- * 了解磁放松动态是设计高效的SMM的关键.
研究的目的:
- * 为了研究三角体体复合体U(Ph(2)BPz(2))(3) 的磁放松特性.
- * 确定旋转放松屏障并探索温度依赖的放松机制.
- * 确定量子道效应并提出基于的新型SMM的设计策略.
主要方法:
- * 交替电流 (ac) 磁性易感度测量.
- * 对AC敏感性的温度和频率依赖性分析.
- *对放松时间的直流 (dc) 场依赖性研究.
主要成果:
- * 在零应用直流电场下,在U{\displaystyle U{\displaystyle Ph} }2) BPz{\displaystyle BPz{\displaystyle U{\displaystyle P} }2)) 中证明了缓慢的磁放松.
- *确定了阿雷尼乌斯行为主导3K以上的放松,产生了U(eff) =20cm(-1的旋转放松屏障.
- * 在较低温度下观察到量子道过程的证据.
结论:
- * U ((Ph ((2) BPz ((2)) ((3) 具有单分子磁铁的特征.
- * 结果表明,通过优化轴对称复合体中的联体场贡献来设计新的 (III) 基SMM的总体策略.
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