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在四面体复合体[Co(SPh]4]2-2-的零场缓慢的磁放松
Joseph M Zadrozny1, Jeffrey R Long
1Department of Chemistry, University of California, Berkeley, California 94720, USA.
Journal of the American Chemical Society
|December 7, 2011
概括
四面体复合体表现出单分子磁铁行为,在低温下显示温度独立放松,在高温下显示热激活行为. 稀释研究显示,分子间相互作用是量子道的媒介.
科学领域:
- 无机化学 无机化学 有机化学
- 材料科学 材料科学 材料科学
- 量子物理学 量子物理学 是一种量子物理学.
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.
- 了解磁放松动态和影响SMM行为的因素对于其实际应用至关重要.
- 由于其电子性质,具有四面体协调环境的复合物是SMM的潜在候选物.
研究的目的:
- 为了研究四面体复合体[Co(SPh) ((4))) ((2-)) 的Ph(4) P(+) 盐的单分子磁铁行为.
- 阐明磁放松机制,包括温度依赖和量子道化.
- 确定分子间相互作用在观察到的磁性特性中的作用.
主要方法:
- 综合和表征[Co(SPh) ((4))) ((2-) 复合体.
- 测量磁性易感度以探测动态磁性.
- 在应用磁场下的可变温度磁性研究.
- 使用等态复合矩阵进行稀释实验.
主要成果:
- [Co(SPh)(4)](2-) 复合体表现出单分子磁铁行为,其基本状态为S = 3/2和轴向零场分裂 (D = -70 cm(-1)).
- 磁放松在非常低的温度下是温度独立的,表明量子道,并且遵循2.5K以上的阿雷尼乌斯行为 (U(eff) = 21(1) cm(-1), τ(0) = 1.0(3) × 10(-7) s).
- 应用磁场 (1kOe) 在更广泛的温度范围内促进阿雷尼乌斯的行为.
- 稀释研究表明,分子间双极相互作用调解了低温量子道通路.
结论:
- [Co(SPh) ((4))) ((2-) 复合体作为单分子磁铁起作用.
- 量子道是一种在低温下显著的放松途径,可能受到分子间相互作用的影响.
- 需要对分子设计进行进一步的研究,以优化SMM性能并抑制实际应用的道化.
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