Orbital angular momentum plays a vital role in various applications, especially magnetic and spintronic properties. There-fore, controlling orbital angular momentum is of paramount importance to both fundamental science and new technologi-cal applications. Many attempts have been made to modulate the ligand-field induced quenching effects of orbital angular momentum to manipulate magnetic properties. However, to date, reported changes in the magnitude of orbital angular momentum are small in both molecular and solid-state magnetic materials. Moreover, no effective methods currently exist to modulate orbital angular momentum. Here, we report a dynamic bond approach to realize a large change in orbital angu-lar momentum. We have developed a Co(II) complex that exhibits coordination number switching between six and seven. This cooperative dynamic bond switching induces considerable modulation of the ligand field, thereby leading to substantial quenching and restoration of the orbital angular momentum. This switching mechanism is entirely different from those of spin-crossover and valence tautomeric compounds, which exhibit switching in spin multiplicity.

中文翻译：

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通过钴 (II) 配合物中的动态键淬灭和恢复轨道角动量

轨道角动量在各种应用中起着至关重要的作用，尤其是磁性和自旋电子特性。因此，控制轨道角动量对基础科学和新技术应用都至关重要。已经进行了许多尝试来调节轨道角动量的配体场诱导猝灭效应以操纵磁性。然而，迄今为止，分子和固态磁性材料中轨道角动量大小的报告变化很小。此外，目前还没有有效的方法来调节轨道角动量。在这里，我们报告了一种动态键方法来实现轨道角动量的大变化。我们开发了一种 Co(II) 复合物，其配位数在 6 和 7 之间切换。这种协同的动态键转换引起了配体场的相当大的调制，从而导致轨道角动量的大量淬灭和恢复。这种转换机制与自旋交叉和价互变化合物的转换机制完全不同，后者表现出自旋多重性的转换。