Metal–Metal-Bonded Fe 4 Clusters with Slow Magnetic Relaxation
Metal–Metal-Bonded Fe 4 Clusters with Slow Magnetic Relaxation
复制标题
具有慢磁弛豫的金属-金属键合 Fe 4 团簇
DOI：
10.1021/acs.inorgchem.2c00865
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发表时间：
2022
影响因子：
4.6
通讯作者：
Hayton, Trevor W.
中科院分区：
文献类型：
--
作者：
Hertler, Phoebe R.;Kautzsch, Linus;Touchton, Alexander J.;Wu, Guang;Hayton, Trevor W.
FeBr 2与Li（N <$CtBu2）（0.5equiv）和Zn 0（2 equiv）的反应导致以中等产率形成形式上混合价的簇合物[Fe 4 Br 2（N <$CtBu2）4]（1）。1与Na（N <$CtBu2）反应生成[Fe 4 Br（N <$CtBu2）5]（2），产率中等。通过零场57 Fe Mo穆斯堡尔谱、X射线晶体学和超导量子干涉仪等手段对1和2进行了表征。它们的四面体[Fe 4]6+核心具有短的Fe-Fe相互作用（约100 μ m）。2.50）。此外，1和2在室温下均表现出S = 7的基态和缓慢的磁弛豫，零场弛豫势垒分别为Ueff = 14.7（4）和15.6（7）cm-1.此外，AC磁化率测量很好地模拟了假设一个Orbach弛豫过程。
Reaction of FeBr2with Li(N═CtBu2) (0.5 equiv) and Zn0(2 equiv) results in the formation of the formally mixed-valent cluster [Fe4Br2(N═CtBu2)4] (1) in moderate yield. The subsequent reaction of1with Na(N═CtBu2) results in formation of [Fe4Br(N═CtBu2)5] (2), also in moderate yield. Both1and2were characterized by zero-field57Fe Mössbauer spectroscopy, X-ray crystallography, and superconducting quantum interference device magnetometry. Their tetrahedral [Fe4]6+cores feature short Fe–Fe interactions (ca. 2.50 Å). Additionally, both1and2displayS= 7 ground states at room temperature and slow magnetic relaxation with zero-field relaxation barriers ofUeff= 14.7(4) and 15.6(7) cm–1, respectively. Moreover, AC magnetic susceptibility measurements were well modeled by assuming an Orbach relaxation process.