在MoS43--桥接Dilanthanide复合体中的强铁磁交换合和单分子磁性
Lucy E Darago1, Monica D Boshart2, Brian D Nguyen2
1Department of Chemistry, University of California, Berkeley, California 94720, United States.
Journal of the American Chemical Society
|May 24, 2021
概括
这项研究合成了新型的4d-4f化合物,在和之间表现出强烈的铁磁交换. 这些材料显示出开发先进的单分子磁铁和散装磁铁材料的潜力.
科学领域:
- 无机化学
- 材料科学
- 磁化学
背景情况:
- 研究新型4d-4f异金属化合物对于推进分子磁性至关重要.
- 了解多核复合体中的金属交换相互作用,有助于设计磁性材料.
研究的目的:
- 合成和描述新的三核4d-4f化合物.
- 研究电子结构和磁性特性,重点是金属对金属的电荷转移和磁性交换.
- 探索这些化合物的潜力作为单分子磁铁.
主要方法:
- 三核4d-4f化合物的合成 [Co(C5Me5) 2][(C5Me5) 2Ln ((μ-S) 2Mo ((μ-S) 2Ln ((C5Me5) 2),1-Ln (Ln = Y,Gd,Tb,Dy).
- 使用UV-Vis-NIR扩散反射光谱,DFT计算,电子磁共振 (EPR) 和磁敏感度测量进行了表征.
- 对慢磁放松研究的电磁易感性分析.
主要成果:
- 化合物表现出由硫介导的低能金属对金属电荷转移从Mo{4d}到L{5d}轨道.
- 观察到显著的电子移位和强烈的铁磁Ln-Mo交换相互作用.
- 化合物1-Gd显示了一个S = 15/2基本状态,具有很大的Gd-Mo交换常数 (J = +16.1(2) cm−1).
- 1-Tb和1-Dy化合物具有缓慢的磁放松,而1-Dy具有最大的热放松屏障 (Ueff = 68 cm−1).
结论:
- 这项研究提出了增强nd-4f磁交换的通用途径.
- 这些发现为设计具有定制性质的新nd-4f单分子磁铁和散装磁性材料开辟了道路.
- 观察到的强磁交换和缓慢放松凸显了这些化合物在分子磁性的潜力.
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