First-principles simulation of an ejected electron produced by monochromatic deposition energy to water at the femtosecond order
Takeshi Kai, Tomohiro Toigawa, Yusuke Matsuya, Yuho Hirata, Tomoya Tezuka, H. Tsuchida, Akinari Yokoya
Abstract
). The earliest formation involves electron thermalization and delocalization dominated by the molecular excitation of water. Our simulation results show that the transient electron dynamics primarily depends on the amount of deposition energy to water; the thermalization time varies from 200 to 500 fs, and the delocalization varies from 3 to 10 nm in this energy range. These features are crucial for determining the earliest single-spur formation and facilitating a sequential simulation from an energy deposition to a chemical reaction in water photolysis or radiolysis. The spur radius obtained from the simulation correlates reasonably with the experimental-based estimations. Our results should provide universalistic insights for analysing ultrafast phenomena dominated by the molecular excitation of water in the femtosecond order.