A molecular dynamics study of a 5 keV C 60 fullerene impact on a two-component organic molecular sample
A molecular dynamics study of a 5 keV C 60 fullerene impact on a two-component organic molecular sample
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5 keV C 60 富勒烯对双组分有机分子样品影响的分子动力学研究
DOI：
10.1002/sia.3527
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发表时间：
2011
影响因子：
1.7
通讯作者：
Ponomarev M
中科院分区：
文献类型：
--
作者：
Ponomarev M
研究了嵌入在苯基体中的c60富勒烯的冲击诱导解吸作为基质辅助二次离子质谱模型。将浓度约0.5%的富勒烯掺入粗粒苯靶中，然后用5kev的富勒烯弹丸撞击。将苯靶与纯苯靶的响应进行比较，观察嵌入分子对基体的影响。研究了三种不同的轨迹。在第一种方法中，从弹丸中射出一个与碳原子连接的单个溅射富勒烯。在第二个实验中，一个未损坏的c60被弹出，而在第三个实验中，没有完整的富勒烯被弹出。在这三种情况下，4-6个富勒烯被推到初始表面之上，但被重新安置到陨石坑边缘，使表层更重、结合更强的成分丰富。可以观察到，溅射的富勒烯与许多基质分子一起被射出，并且被射出的富勒烯的内能有一个小的下降，这与周围基质分子与大分子的逐渐分离相对应。这种蒸发冷却可能为矩阵辅助SIMS提供潜在的好处。版权所有©2010 John Wiley & Sons， Ltd
A study has been made to explore impact‐induced desorption of C60fullerenes embedded in a benzene matrix as a model of matrix assisted secondary ion mass spectrometry. A fullerene concentration of about 0.5% was incorporated in a coarse‐grained benzene target and then struck by a 5 keV fullerene projectile. The response of the benzene target was compared with a pure benzene target to observe the effects of the embedded molecules on the matrix.Three different trajectories were investigated. In the first, a single sputtered fullerene was ejected joined to a carbon atom from the projectile. In the second, an undamaged C60was ejected, and in the third, no intact fullerenes were ejected. In all three cases, 4–6 fullerenes were pushed above the initial surface but were relocated into the crater rim, enriching the surface layer with the heavier and more strongly bound component.It is observed that the sputtered fullerenes are ejected with a number of matrix molecules, and that there is a small decrease in the internal energy of the ejected fullerene that corresponds to the gradual separation of the surrounding matrix molecules from the larger molecule. This evaporative cooling may provide a potential benefit to Matrix Assisted SIMS. Copyright © 2010 John Wiley & Sons, Ltd.