Charge transfer in dissociating iodomethane and fluoromethane molecules ionized by intense femtosecond X-ray pulses

Rebecca Boll (1, 2) , Benjamin Erk (1) , Ryan Coffee (3) , Sebastian Trippel (1) , Thomas Kierspel (4, 1) , Cédric Bomme (1) , John D. Bozek (3) , Mitchell Burkett (5) , Sebastian Carron (3) , Ken R. Ferguson (3) , Lutz Foucar (6) , Jochen Küpper (1, 4) , Tatiana Marchenko (7) , Catalin Miron (8, 9) , Minna Patanen (10, 8) , Timur Osipov (3) , Sebastian Schorb (3) , Marc Simon (7) , Michelle Swiggers (3) , Simone Techert (11, 1, 12) , Kiyoshi Ueda (13) , Christoph Bostedt (14, 15, 3) , Daniel Rolles (1, 5) , Artem Rudenko (5)

1 DESY - Deutsches Elektronen-Synchrotron [Hamburg]
2 MPIK - Max Planck Institute for Nuclear Physics
3 SLAC - SLAC National Accelerator Laboratory
4 UHH - Universität Hamburg
5 Kansas State University
6 Max Planck Institute for Medical Research [Heidelberg]
7 LCPMR - Laboratoire de Chimie Physique - Matière et Rayonnement
8 SSOLEIL - Synchrotron SOLEIL
9 NIPNE - Horia Hulubei National Institute of Physics and Nuclear Engineering
10 University of Oulu
11 Georg-August-University = Georg-August-Universität Göttingen
12 MPI-BPC - Max Planck Institute for Biophysical Chemistry
13 IMRAM
14 ANL - Argonne National Laboratory [Lemont]
15 Northwestern University [Evanston]

Ultrafast electron transfer in dissociating iodomethane and fluoromethane molecules was studied at the Linac Coherent Light Source free-electron laser using an ultraviolet-pump, X-ray-probe scheme. The results for both molecules are discussed with respect to the nature of their UV excitation and different chemical properties. Signatures of long-distance intramolecular charge transfer are observed for both species, and a quantitative analysis of its distance dependence in iodomethane is carried out for charge states up to I21+. The reconstructed critical distances for electron transfer are in good agreement with a classical over-the-barrier model and with an earlier experiment employing a near-infrared pump pulse.

Domaines: Physique [physics]

Rebecca Boll, Benjamin Erk, Ryan Coffee, Sebastian Trippel, Thomas Kierspel, et al.. Charge transfer in dissociating iodomethane and fluoromethane molecules ionized by intense femtosecond X-ray pulses. Structural Dynamics, 2016, 3 (4), pp.043207. ⟨10.1063/1.4944344⟩. ⟨hal-01304690⟩