在Cu-氧化物复合体中,热磁双稳定性,巨大的负热膨胀和THz热诱导的切换
Kristina Smirnova1, Irina Golomolzina1, Sergey Fokin1
1International Tomography Center SB RAS, Institutskaya str., 3a, Novosibirsk, 630090, Russia.
Angewandte Chemie (International ed. in English)
|October 9, 2025
概括
基于分子的磁铁通过热诱导激发自旋状态捕获 (TIESST) 来实现双稳定性. 这项研究报告了第一个Cu (II) - 氧化物复合体,其TIESST驱动的双稳定性高达116K.
科学领域:
- 分子磁力学分子磁力学
- 材料科学 材料科学 材料科学
- 超分子化学 超分子化学
背景情况:
- 基于分子的磁铁的可靠性对于功能性设备至关重要.
- 热诱导激发自旋状态捕获 (TIESST) 提供了一种稳定不同自旋状态的方法.
- 之前的异素Cu ((II) - 氧化物化合物没有显示TIESST效应.
研究的目的:
- 报告第一个Cu(II) 氧化物复合体表现出TIESST驱动的双稳定性.
- 描述这个新的复合体的TIESST特性和放松动态.
- 研究旋转交叉系统中旋转放松的机制.
主要方法:
- 一个新的Cu (II) - 氧化物复合物的合成和特征.
- 测量磁敏度以确定旋转过渡和TIESST温度.
- 在过渡过程中分析晶体结构的X射线衍射 (XRD) 研究.
- 时间分辨率测量以研究放松动态.
主要成果:
- 第一个Cu (II) - 氧化物复合体证明了TIESST驱动的双稳定性高达116K.
- 在旋转过渡温度附近观察到一个30 K的歇斯底里循环 (T1/2↑ = 144 K,T1/2↓ = 114 K).
- 被困的兴奋状态表现为缓慢放松 (>9小时在95K) 和通过THz脉冲快速切换 (<50毫秒).
- XRD证实了被困和稳定的相的共存,揭示了自催化放松机制.
结论:
- 这项工作介绍了一种具有显著TIESST驱动的可视化稳定的新型Cu (II) 氧化复合物.
- 由于其缓慢放松和快速切换能力,该综合体展示了分子记忆器件的潜力.
- 自催化放松机制的发现为了解和控制分子系统中的自旋动力学开辟了新的途径.
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