Charge and Nuclear Dynamics Induced by Deep Inner-Shell Multiphoton Ionization of CH3I Molecules by Intense X‑ray Free-Electron Laser Pulses
journal contributionposted on 17.12.2015, 08:57 by Koji Motomura, Edwin Kukk, Hironobu Fukuzawa, Shin-ichi Wada, Kiyonobu Nagaya, Satoshi Ohmura, Subhendu Mondal, Tetsuya Tachibana, Yuta Ito, Ryosuke Koga, Tsukasa Sakai, Kenji Matsunami, Artem Rudenko, Christophe Nicolas, Xiao-Jing Liu, Catalin Miron, Yizhu Zhang, Yuhai Jiang, Jianhui Chen, Mailam Anand, Dong Eon Kim, Kensuke Tono, Makina Yabashi, Makoto Yao, Kiyoshi Ueda
In recent years, free-electron lasers operating in the true X-ray regime have opened up access to the femtosecond-scale dynamics induced by deep inner-shell ionization. We have investigated charge creation and transfer dynamics in the context of molecular Coulomb explosion of a single molecule, exposed to sequential deep inner-shell ionization within an ultrashort (10 fs) X-ray pulse. The target molecule was CH3I, methane sensitized to X-rays by halogenization with a heavy element, iodine. Time-of-flight ion spectroscopy and coincident ion analysis was employed to investigate, via the properties of the atomic fragments, single-molecule charge states of up to +22. Experimental findings have been compared with a parametric model of simultaneous Coulomb explosion and charge transfer in the molecule. The study demonstrates that including realistic charge dynamics is imperative when molecular Coulomb explosion experiments using short-pulse facilities are performed.