The physics of energetic fullerene projectile penetration, damage creation and sputtering in organic solids is investigated via molecular dynamics simulations. Two models are used, the first one based on a full atomistic description of the target and the second one, using a coarse-grain prescription that was recently developed and tested for a benzene molecular crystal [E. Smiley, Z. Postawa, I.A. Wojciechowski, N. Winograd, B. J. Garrison, Appl. Surf. Sci. 252 (2006) 6436]. The results explore the mechanism of energy transfer from the C60 projectile to the organic target atoms/molecules through the comparison with significantly different projectiles (Argon) and samples (Ag crystal). The effects of the projectile energy on the penetration and fast energy transfer processes (200 fs) are also delineated. The second part of the results investigates the 'long term' consequences (20-50 ps) of fullerene impacts in hydrocarbon sample surfaces. In an icosane (C20H42) solid, a 5 keV C60 projectile induces a crater of ∼10 nm diameter surrounded by a ∼4 nm wide rim and ejects ∼70 intact molecules. More than 75% of the fragments generated by the fullerene in the surface are also sputtered away by the end of the event. The perspective considers the capabilities of fullerene projectiles for depth profile analysis of molecular samples by particle-induced desorption mass spectrometry.
|Original language||English (US)|
|Number of pages||6|
|Journal||Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms|
|Issue number||1 SPEC. ISS.|
|State||Published - Feb 2007|
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics