中国科学院福建物质结构研究所盛天录课题组揭示了具有低能桥的混合价化合物在不同氧化态下的电子传递过程。 相关论文于2020年11月23日发表在《德国应用化学》。

在该研究中，以不同氧化态的具有异氰金属配体桥的混合价化合物作为研究电子转移（ET）过程的模型。

因此，研究人员组合成了一系列具有[Fe-CN-Ru-NC-Fe]n+（n=2-4）的三元甲基异氰金属桥联化合物并对其进行了详细表征，其中，单电子氧化产物（N3+）和双电子氧化产物（N4+）化合物具有一个异氰基金属桥，其能量分别低于和略高于终端金属中心的能量。对于N 4+化合物，可以在红外时间尺度上同时观察到桥态（Fe II‐Ru III‐Fe II）和混合价态（Fe III‐Ru II‐Fe II或Fe II‐Ru II‐Fe III），在基态势能面（PES）的支持下，随着Cp甲基基团数的增加，ET激发的混合价态变得越来越稳定。而对于N4+化合物，随着施主的增强，ET激发的桥态（Fe III‐Ru II‐Fe III）变得越来越稳定，甚至由于Fe和Ru之间的强电子耦合而变成基态。

该发现可能有助于更好地理解自然界中的电子转移过程，并有助于新型电子转移材料的设计。

附：英文原文

Title: Electron Transfer Process in Mixed Valence Compounds with Low‐lying Energy Bridge in Different Oxidation States

Author: Yu-Ying Yang, Xiao-Quan Zhu, Jean-Pierre Launay, Cheng-Bin Hong, Shao-Dong Su, Yue-Hong Wen, Xin-Tao Wu, Tian-Lu Sheng

Issue&Volume: 23 November 2020

Abstract: In this work, the mixed valent compounds with the iso‐cyanidometal‐ligand bridge in different oxidation states are used as models for the investigation of ET process. Thus, we synthesized and fully characterized a series of trimetallic isocyanidometal‐bridged compounds with [Fe‐CN‐Ru‐NC‐Fe]  n+  (n = 2 ‐ 4), in which the one‐electron oxidation product (  N  3+  ) and two‐electron oxidation product (  N  4+  ) compounds possess an isocyanidometal‐bridge whose energy is respectively lower and slightly higher than the terminal metal centers energies. For the  N  4  +  compounds, the bridge‐state (Fe  II  ‐Ru  III  ‐Fe  II  ) and mixed valence states (Fe  III  ‐Ru  II  ‐Fe  II  or Fe  II  ‐Ru  II  ‐Fe  III  ) could be simultaneous observed on the IR time‐scale, supported by the ground state Potential Energy Surface (PES) that indicates as the number of methyl groups of Cp increases the ET excited mixed valence state becomes more and more stable. Whereas, for the  N  4  +  compounds, as the donor becomes stronger the ET excited bridge state (Fe  III  ‐Ru  II  ‐Fe  III  ) becomes more and more stable, and even becomes ground state due to the strong electronic coupling between Fe and Ru. Our findings might be helpful for better understanding the ET process in nature and for the design of novel electron transfer materials.

DOI: 10.1002/anie.202014501

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202014501