Cluster SIMS of Organic Materials: Theoretical Insights

Macromolecular Sample Sputtering by Large Ar and CH4 Clusters: Elucidating Chain Size and Projectile Effects with Molecular Dynamics

“…To shed light on the physical processes of large cluster bombardment of surfaces, theoretical studies using molecular dynamics (MD) simulations have proven to be very useful. The main results have been discussed in review articles. − In particular, several studies were devoted to the explanation of the effects of the cluster energy and nuclearity in the case of Ar cluster bombardment of various solids. − The effect of the incidence angle on the sputtering of organic solids has been investigated to some extent by Czerwinski et al for small molecules (solid benzene) and two different Ar cluster sizes (Ar 366 and Ar 2953 ) . Those authors analyzed the difference between small and large cluster sputtering, with the former exhibiting a plateau between 0° and 45°, while the latter showed a pronounced maximum around 45°.…”

Dynamics of l-Phenylalanine Sputtering by Argon Cluster Bombardment

“…Such simulations are limited by the available interatomic potentials (or “force fields”) that describe the interactions between atoms constituting the target molecules. Available simulations mostly used the AIREBO potential that allows the study of hydrocarbons, including their fragmentation and reactions; relevant studies of cluster-induced processes have been performed, for example, for benzene and polystyrene targets. ,− Recently the so-called ReaxFF potentials have become available that permit performance of reactive molecular dynamics simulations for a larger class of organic molecules containing in addition to C and H also N, O, and other relevant atom species. − Due to their large computational complexity, these potentials have up to now only rarely been employed for the study of irradiation-induced processes …”

Cluster impacts in organics: microscopic models and universal sputtering curves

“…The quest of the ideal cluster projectile for maximum sputtering and ion yields, or for minimum damage upon molecular depth profiling, has triggered a number of theoretical studies of cluster surface interactions, in particular, with organic materials. These theoretical studies and the fundamentals of organic materials sputtering have been reviewed in recent book chapters . In this article, we compare and discuss the results of a series of molecular dynamics simulations involving two hydrocarbon targets and a variety of projectiles, going from single atoms of Ga and Bi to large and massive cluster such as Ar 2000 and Au 400 .…”