Wang Ming, Zhao Chong-Yang, Zhou Hai-Yan, Zhao Yue, Li Ya-Ke, Ma Jia-Bi
Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, 100081 Beijing, China.
Wilhelm-Ostwald Institut für Physikalische und Theoretische Chemie Universität Leipzig Linnéstr. 2, 04103 Leipzig, Germany.
J Chem Phys. 2021 Feb 7;154(5):054307. doi: 10.1063/5.0029180.
The activation and hydrogenation of nitrogen are central in industry and in nature. Through a combination of mass spectrometry and quantum chemical calculations, this work reports an interesting result that scandium nitride cations ScN can activate sequentially H and N, and an amido unit (NH) is formed based on density functional theory calculations, which is one of the inevitable intermediates in the N reduction reactions. If the activation step is reversed, i.e., sequential activation of first N and then H, the reactivity decreases dramatically. An association mechanism, prevalent in some homogeneous catalysis and enzymatic mechanisms, is adopted in these gas-phase H and N activation reactions mediated by ScN cations. The mechanistic insights are important to understand the mechanism of the conversion of H and N to NH synthesis under ambient conditions.
氮的活化和氢化在工业和自然界中都至关重要。通过结合质谱分析和量子化学计算，这项工作报道了一个有趣的结果：氮化钪阳离子ScN可以依次活化氢和氮，并且基于密度泛函理论计算形成了一个氨基单元（NH），这是氮还原反应中不可避免的中间体之一。如果活化步骤相反，即先活化氮再活化氢，反应活性会急剧下降。在这些由ScN阳离子介导的气相氢和氮活化反应中，采用了一种在一些均相催化和酶促机制中普遍存在的缔合机制。这些机理见解对于理解在环境条件下氢和氮转化为氨合成的机制很重要。
