Münzfeld L, Schoo C, Bestgen S, Moreno-Pineda E, Köppe R, Ruben M, Roesky P W
Institute of Inorganic Chemistry, Karlsruhe Institute of Technology (KIT), Engesserstraße 15, 76131, Karlsruhe, Germany.
Institute of Nanotechnology (INT), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, D-76344, Eggenstein-Leopoldshafen, Germany.
Nat Commun. 2019 Jul 17;10(1):3135. doi: 10.1038/s41467-019-10976-6.
Sandwich complexes are an indispensable part of organometallic chemistry, which is becoming increasingly important in the field of lanthanide-based single molecule magnets. Herein, a fundamental class of pure sandwich complexes, [(η-CH)Ln(η-CH)] (Ln=Nd, Sm, Dy, Er), is reported. These neutral and sandwiched lanthanide compounds exclusively contain fully π-coordinated coplanar eight and nine membered CH rings. The magnetic properties of these compounds are investigated, leading to the observation of slow relaxation of the magnetization, including open hysteresis loops up to 10 K for the Er(III) analogue. Fast relaxation of the magnetization is likewise observed near zero field, a highly important characteristic for quantum information processing schemes. Our synthetic strategy is straightforward and utilizes the reaction of [(η-CH)LnI(thf)] complexes with [K(CH)]. Although all compounds are fully characterized, structural details of the title compounds can also be deduced by Raman spectroscopy only.
夹心配合物是有机金属化学中不可或缺的一部分，在基于镧系元素的单分子磁体领域正变得越来越重要。在此，报道了一类基本的纯夹心配合物[(η⁵-C₅H₅)₂Ln(η⁵-C₅H₅)]（Ln = Nd、Sm、Dy、Er）。这些中性夹心镧系化合物仅包含完全π配位的共面八元环和九元环C₅H₅环。对这些化合物的磁性进行了研究，结果观察到磁化强度的缓慢弛豫，包括对于铒（III）类似物在高达10 K时出现的开放磁滞回线。在接近零场时同样观察到了磁化强度的快速弛豫，这是量子信息处理方案的一个非常重要的特征。我们的合成策略很简单，利用了[(η⁵-C₅H₅)LnI(thf)₂]配合物与[K(C₅H₅)]的反应。尽管所有化合物都得到了充分表征，但标题化合物的结构细节也仅通过拉曼光谱就能推导出来。
