Bouncing and sticking collisions of organic nanoparticles: Atomistic study

Context. Whether nanoparticles bounce or stick during collisions determines whether particles grow fragment, hence shaping collision-induced agglomeration processes. The collision behavior of organic matter may strongly differ from that silica ice grains. Aims. We explore the microscopic processes underlying bouncing nanoparticles. Methods. Molecular dynamics simulations based on a reactive potential, which follow molecular motion an atomistic scale, are used. Results. For exemplary case glycolic acid molecules, warm (250 K) always show sticking, while at low velocities (2.5 m s −1 ) cold (100 exhibit considerable probability for bouncing. This can be traced back to distant electrostatic repulsion certain orientations; this prevents closer approach, van der Waals and H-bonded interactions would lead sticking. At higher temperatures, vibrations conformational flexibility average over nanoparticle interaction, such attraction dominates is prevented. Our results in qualitative agreement with laboratory experiments. Conclusions. Organic distinctly influences