电子结构和缓慢的磁放松低坐标周期性基氨基碳酸稳定铁I) 复合体
Prinson P Samuel1, Kartik Chandra Mondal, Nurul Amin Sk
1Institut für Anorganische Chemie, Georg-August-Universität , Tammannstrasse 4, D-37077, Göttingen, Germany.
Journal of the American Chemical Society
|July 30, 2014
概括
通过周期性基氨基碳稳定新的铁I复合物表现出单分子磁体的特性. 这些发现促进了对低价值铁化学和磁性材料的理解.
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
- 量子化学 是一个量子化学.
背景情况:
- 由于其独特的电子结构和潜在的应用,低价值铁复合体具有重大兴趣.
- 循环氨基) 碳 (cAACs) 是多功能联体,能够稳定不寻常的金属氧化状态.
研究的目的:
- 合成和表征由cAAC配体稳定的新型二和三坐标Fe (I) 复合物.
- 研究这些Fe (I) 化合物的磁性和电子结构.
- 探索它们作为单分子磁铁的潜力.
主要方法:
- 合成 (cAAC) 2FeCl和[cAAC) 2Fe][B][C6F5) ]4复合物的合成.
- 测量磁感应度的测量.
- 莫斯巴乌尔光谱法. 莫斯巴乌尔光谱法.
- 高频电子偏磁共振 (EPR) 光谱. 高频电子偏磁共振 (EPR) 光谱.
- 使用MOLCAS.使用的初始计算 (CASSCF/CASPT2/RASSI-SO)
主要成果:
- 鉴定证实了两个复合体的Fe(I) 氧化状态和S = 3/2旋转基本状态.
- 这两种化合物都表现出缓慢的磁放松,这是单分子磁铁在应用直流磁场下的特性.
- 在EPR测量中,发现了很大的,正的零场分裂 (∼20.4cm(-1)) 和化合物2的轻松平面异构性.
- 理论计算支持了关于电子结构和磁性属性的实验发现.
结论:
- 这项研究成功地准备和表征了由cAAC配体稳定的新型Fe ((I)) 复合物.
- 这些复合体表现出单分子磁铁行为,归因于它们的S = 3/2基本状态和显著的零场分裂.
- 这些发现有助于开发分子磁性材料,并加深对低价值铁化学的理解.
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