Sun Zhang, Sun Shutao, Liu Hongtao, Zhu Qihe, Gao Zhen, Tang Zichao
Beijing National Laboratory for Molecular Sciences, Center of Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, People's Republic of China.
J Phys Chem A. 2008 Nov 20;112(46):11566-74. doi: 10.1021/jp805837b. Epub 2008 Oct 23.
The reactions between lead vapored by laser ablation and different aromatic molecules (C6H6, C5H5N, C4H4O, or C4H5N) seeded in argon carrier gas were studied by a reflectron time-of-flight mass spectrometer (RTOF-MS) with a photoelectron spectrometer. The adiabatic electron affinities (EAs) of the dominant anionic products PbmC6H5(-), Pb(m)C5H4N(-) (m = 1-4) and Pb(m)C4H3 (-), Pb(m)C4H4N(-) (m = 1-3) dehydrogenated complexes are obtained from the photoelectron spectra with 308 and 193 nm photon, respectively. It is found that the EAs of Pb(m)C4H4N are higher than those of Pb(m)C6H5, Pb(m)C5H4N, and Pb(m)C4H3O with the same metal number m. The possible structures for Pb(m)C4H4N(-) complexes were calculated with density functional theory (DFT) and the most stable structure was confirmed. The adiabatic detachment energies for the most stable structure were in agreement with the experimental PES results. The calculated density of state (DOS) agrees with the experimental PES spectrum well. It was confirmed by the theoretical calculations that the C4H4N group bonds on lead clusters through the Pb-N sigma bond.
利用带有光电子能谱仪的反射式飞行时间质谱仪（RTOF-MS），研究了激光烧蚀产生的铅蒸气与氩载气中不同芳香族分子（C6H6、C5H5N、C4H4O或C4H5N）之间的反应。分别用308和193nm光子的光电子能谱，得到了主要阴离子产物PbmC6H5(-)、Pb(m)C5H4N(-)（m = 1 - 4）以及脱氢配合物Pb(m)C4H3(-)、Pb(m)C4H4N(-)（m = 1 - 3）的绝热电子亲和能（EA）。结果发现，相同金属数m时，Pb(m)C4H4N的EA高于Pb(m)C6H5、Pb(m)C5H4N和Pb(m)C4H3O的EA。采用密度泛函理论（DFT）计算了Pb(m)C4H4N(-)配合物的可能结构，并确定了最稳定结构。最稳定结构的绝热脱附能与实验光电子能谱结果一致。计算得到的态密度（DOS）与实验光电子能谱吻合良好。理论计算证实，C4H4N基团通过Pb-N σ键与铅簇结合。
