Khanna Vaibhav, Singh Roshan, Claes Pieterjan, Nguyen Minh Tho, Fielicke André, Janssens Ewald, Lievens Peter, McGrady John E
Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, U.K.
Quantum Solid-State Physics, Department of Physics and Astronomy, KU Leuven, Celestijnenlaan 200 D, B-3001 Leuven, Belgium.
J Phys Chem A. 2022 Mar 17;126(10):1617-1626. doi: 10.1021/acs.jpca.1c10027. Epub 2022 Mar 3.
A comparison of DFT-computed and measured infrared spectra reveals the ground state structures of a series of gas-phase silicon clusters containing a common Mn unit. MnSi and [MnSi] are both axially symmetric, allowing for a clean separation of the vibrational modes into parallel (a) and perpendicular (e) components. Information about the Mn-Mn and Mn-Si bonding can be extracted by tracing the evolution of these modes as the cluster increases in size. In [MnSi], where the antiprismatic core is capped on both hexagonal faces, a relatively simple spectrum emerges that reflects a geometry. In cases where the cluster is more polar, either because there is no capping atom in the lower face (MnSi) or the capping atom is present but displaced off the principal axis (MnSi), the spectra include additional features derived from vibrational modes that are forbidden in the parent antiprism.
密度泛函理论（DFT）计算的红外光谱与实测红外光谱的比较揭示了一系列含有共同锰单元的气相硅簇的基态结构。MnSi和[MnSi]均为轴对称结构，使得振动模式能够清晰地分离为平行（a）和垂直（e）分量。通过追踪随着簇尺寸增大这些模式的演变，可以提取有关锰-锰和锰-硅键合的信息。在[MnSi]中，反棱柱形核心在两个六边形面上均有盖帽，出现了相对简单的光谱，反映了一种几何结构。在簇更具极性的情况下，要么是因为下表面没有盖帽原子（MnSi），要么是存在盖帽原子但偏离主轴（MnSi），光谱中会包含源自母体反棱柱中禁戒振动模式的额外特征。
