Femtosecond response of polyatomic molecules to ultra-intense hard X-rays

Journal Article · Wed May 31 00:00:00 EDT 2017 · Nature (London)

DOI:https://doi.org/10.1038/nature22373· OSTI ID:1376141

Rudenko, A. ^[1]; Inhester, L. ^[2]; Hanasaki, K. ^[3]; Li, X. ^[1]; Robatjazi, S. J. ^[1]; Erk, B. ^[4]; Boll, R. ^[5]; Toyota, K. ^[2]; Hao, Y. ^[6]; Vendrell, O. ^[7]; Bomme, C. ^[4]; Savelyev, E. ^[4]; Rudek, B. ^[8]; Foucar, L. ^[9]; Southworth, S. H. ^[10]; Lehmann, C. S. ^[11]; Kraessig, B. ^[10]; Marchenko, T. ^[12]; Simon, M. ^[12]; Ueda, K. ^[13] ; Ferguson, K. R. ^[14]; Bucher, M. ^[15]; Gorkhover, T. ^[16]; Carron, S. ^[14]; Alonso-Mori, R. ^[14]; Koglin, J. E. ^[14]; Correa, J. ^[17]; Williams, G. J. ^[18]; Boutet, S. ^[14]; Young, L. ^[19]; Bostedt, C. ^[20]; Son, S. -K. ^[2]; Santra, R. ^[21]; Rolles, D. ^[22]

---

1. Kansas State Univ., Manhattan, KS (United States). J. R. Macdonald Laboratory, Department of Physics
2. Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); The Hamburg Centre for Ultrafast Imaging, Hamburg (Germany)
3. Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); The Hamburg Centre for Ultrafast Imaging, Hamburg (Germany); Tohoku University, Sendai (Japan). Department of Chemistry, Graduate School of Science
4. Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
5. Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Max Planck Institute for Nuclear Physics, Heidelberg
6. Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); The Hamburg Centre for Ultrafast Imaging, Hamburg (Germany); University of Science and Technology Beijing (China). Department of Physics
7. Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); The Hamburg Centre for Ultrafast Imaging, Hamburg (Germany); Aarhus University (Denmark). Department of Physics and Astronomy
8. Physikalisch-Technische Bundesanstalt (PTB), Braunschweig (Germany)
9. Max Planck Institute for Medical Research, Heidelberg (Germany)
10. Argonne National Lab. (ANL), Lemont, IL (United States)
11. Argonne National Lab. (ANL), Lemont, IL (United States); Philipps-Universität Marburg, Marburg (Germany). Faculty of Chemistry
12. Sorbonne Universites, UPMC Universite Paris 06, CNRS, LCP-MR (UMR 7614) (France)
13. Tohoku University, Sendai (Japan). Institute of Multidisciplinary Research for Advanced Materials
14. SLAC National Accelerator Lab., Menlo Park, CA (United States). Linac Coherent Light Source (LCLS)
15. Argonne National Lab. (ANL), Lemont, IL (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States). Linac Coherent Light Source (LCLS)
16. SLAC National Accelerator Lab., Menlo Park, CA (United States). Linac Coherent Light Source (LCLS); Institut fur Optik und Atomare Physik, Technische Universitat Berlin (Germany)
17. Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
18. SLAC National Accelerator Lab., Menlo Park, CA (United States). Linac Coherent Light Source (LCLS); Brookhaven National Lab. (BNL), Upton, NY (United States). National Synchrotron Light Source II (NSLS-II)
19. Argonne National Lab. (ANL), Lemont, IL (United States); Univ. of Chicago, IL (United States). Department of Physics
20. Argonne National Lab. (ANL), Lemont, IL (United States); Northwestern Univ., Evanston, IL (United States). Department of Physics and Astronomy
21. Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); The Hamburg Centre for Ultrafast Imaging, Hamburg (Germany); University of Hamburg (Germany). Department of Physics
22. Kansas State Univ., Manhattan, KS (United States). J. R. Macdonald Laboratory, Department of Physics; Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

We report x-ray free-electron lasers enable the investigation of the structure and dynamics of diverse systems, including atoms, molecules, nanocrystals and single bioparticles, under extreme conditions. Many imaging applications that target biological systems and complex materials use hard X-ray pulses with extremely high peak intensities (exceeding 10²⁰ watts per square centimetre). However, fundamental investigations have focused mainly on the individual response of atoms and small molecules using soft X-rays with much lower intensities. Studies with intense X-ray pulses have shown that irradiated atoms reach a very high degree of ionization, owing to multiphoton absorption, which in a heteronuclear molecular system occurs predominantly locally on a heavy atom (provided that the absorption cross-section of the heavy atom is considerably larger than those of its neighbours) and is followed by efficient redistribution of the induced charge. In serial femtosecond crystallography of biological objects—an application of X-ray free-electron lasers that greatly enhances our ability to determine protein structure—the ionization of heavy atoms increases the local radiation damage that is seen in the diffraction patterns of these objects and has been suggested as a way of phasing the diffraction data. On the basis of experiments using either soft or less-intense hard X-rays, it is thought that the induced charge and associated radiation damage of atoms in polyatomic molecules can be inferred from the charge that is induced in an isolated atom under otherwise comparable irradiation conditions. Here we show that the femtosecond response of small polyatomic molecules that contain one heavy atom to ultra-intense (with intensities approaching 10²⁰ watts per square centimetre), hard (with photon energies of 8.3 kiloelectronvolts) X-ray pulses is qualitatively different: our experimental and modelling results establish that, under these conditions, the ionization of a molecule is considerably enhanced compared to that of an individual heavy atom with the same absorption cross-section. This enhancement is driven by ultrafast charge transfer within the molecule, which refills the core holes that are created in the heavy atom, providing further targets for inner-shell ionization and resulting in the emission of more than 50 electrons during the X-ray pulse. Fnally, our results demonstrate that efficient modelling of X-ray-driven processes in complex systems at ultrahigh intensities is feasible.

• Research Organization: Brookhaven National Laboratory (BNL), Upton, NY (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: SC0012704; FG02-86ER13491; AC02-06CH11357; AC02-76SF00515
• OSTI ID: 1376141
• Report Number(s): BNL-114081-2017-JA
• Journal Information: Nature (London), Vol. 546, Issue 7656; ISSN 0028-0836
• Publisher: Nature Publishing Group
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS