Fielicke André, Ratsch Christian, von Helden Gert, Meijer Gerard
Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany.
J Chem Phys. 2007 Dec 21;127(23):234306. doi: 10.1063/1.2806176.
Far-infrared absorption spectra of small neutral and cationic niobium clusters containing five to nine Nb atoms have been obtained by multiple photon dissociation spectroscopy of their argon complexes. The experimental far-IR spectra are recorded in the 85-600 cm(-1) region and cover the range of the structure-specific vibrational fundamentals, i.e., the finger-print range, for these metal clusters. The experiments are accompanied by quantum chemical calculations employing the density-functional theory. A comparison of the experimental and calculated far-IR spectra allows to identify the cluster structures. Although the experimental spectra for clusters containing five, six, eight, and nine Nb atoms are very different for cationic and neutral clusters, the comparison with theory reveals that, nevertheless, the overall geometries for cations and neutrals are very similar, except for Nb(6) (0+).
通过对含五至九个铌原子的小型中性和阳离子铌团簇的氩配合物进行多光子解离光谱，获得了它们的远红外吸收光谱。实验远红外光谱记录在85 - 600 cm(-1)区域，覆盖了这些金属团簇结构特异性振动基频的范围，即指纹范围。实验同时进行了采用密度泛函理论的量子化学计算。实验和计算的远红外光谱的比较有助于识别团簇结构。尽管含五个、六个、八个和九个铌原子的团簇的阳离子和中性团簇的实验光谱非常不同，但与理论的比较表明，除了Nb(6)(0+)外，阳离子和中性团簇的整体几何结构非常相似。
