Schulich Faculty of Chemistry , Technion, Haifa 32000, Israel.
J Phys Chem A. 2013 Nov 21;117(46):11856-65. doi: 10.1021/jp403031p. Epub 2013 Jul 10.
We report the observation and structural analysis of novel indium carbide gas phase cluster ions generated by bombardment of a clean indium surface by keV C60(–) ions. Positive In(m)C(n)(+) (m = 1–21, 1 ≤ n ≤ 9) ions were ejected off the surface and analyzed mass spectrometrically. C60(–) ion beam irradiation is shown to be an efficient way of producing new kinds of gas phase carbide ions with relatively balanced stoichiometries. The rise kinetics of the ion signal (immediate jump within the beam opening time to a plateau value) indicates that the formation/ejection of the carbide ions constitute a single impact event. In3C2(+) was found to be the most abundant carbide cluster ion. Optimal geometries of the different clusters were derived via density functional theory calculations. The acetylenic/cumulenic nature of the impact emitted cluster ions is manifested by the high abundance of In2C2(+), In3C2(+), and the calculated structures for In(m)C(n)(+) (m = 3–4, n = 2–8). Odd/even intensity alternations in the In3C(n)(+) (n = 1–8) and In4C(n)(+) (n = 1–9) abundances are observed and rationalized by the calculations.
我们报告了通过用 keV C60(–)离子轰击清洁的铟表面而产生的新型碳化铟气相团簇离子的观察和结构分析。正 In(m)C(n)(+)（m = 1-21，1 ≤ n ≤ 9）离子从表面被喷射出来，并进行了质谱分析。C60(–)离子束辐照被证明是一种有效方法，可以产生具有相对平衡化学计量比的新型气相碳化物离子。离子信号的上升动力学（在束开启时间内立即跃升到平台值）表明，碳化物离子的形成/喷射构成单个撞击事件。In3C2(+)被发现是最丰富的碳化物团簇离子。通过密度泛函理论计算得出了不同团簇的最佳几何形状。冲击发射的团簇离子的炔基/累积性质通过高丰度的 In2C2(+)、In3C2(+)和计算出的 In(m)C(n)(+)（m = 3-4，n = 2-8）结构表现出来。In3C(n)(+)（n = 1-8）和 In4C(n)(+)（n = 1-9）丰度中的奇数/偶数强度交替被观察到，并通过计算得到了合理化。
