# CFEL-DESYT

 2020-02-1209:47 [PUBDB-2020-00697] Journal Article et al Observation of the fastest chemical processes in the radiolysis of water Science 367(6474), 179-182 (2020) [10.1126/science.aaz4740]   Elementary processes associated with ionization of liquid water provide a framework for understanding radiation-matter interactions in chemistry and biology. Although numerous studies have been conducted on the dynamics of the hydrated electron, its partner arising from ionization of liquid water, H2O+, remains elusive. [...] Fulltext: PDF PDF (PDFA); 2019-12-1712:49 [PUBDB-2019-05333] Journal Article et al Time-resolved ionization measurements with intense ultrashort XUV and X-ray free-electron laser pulses Laser and particle beams 37(2), 235 - 241 (2019) [10.1017/S0263034619000326]   Modern free-electron lasers (FEL) operating in XUV (extreme ultraviolet) or X-ray range allow an access to novel research areas. An example is the ultrafast ionization of a solid by an intense femtosecond FEL pulse in XUV which consequently leads to a change of the complex index of refraction on an ultrashort timescale [...] Restricted: PDF PDF (PDFA); 2019-12-1712:45 [PUBDB-2019-05331] Journal Article et al Time-resolved investigation of the optical phase change as a potential diagnostics tool for extreme-ultraviolet free-electron-laser pump and optical probe experiments Optics letters 45(1), 33 - 36 (2020) [10.1364/OL.45.000033]   Measurement of transient optical properties (reflectivity and transmissivity) is performed widely in extreme-ultraviolet (XUV) pump–optical probe experiments to study the transient state of irradiated materials. In order to extend the material diagnostics, here we propose an additional measurement of the transient phase change of the optical probe pulse. [...] Fulltext: PDF PDF (PDFA); 2019-12-0411:11 [PUBDB-2019-04720] Journal Article et al Controlled strong excitation of silicon as a step towards processing materials at sub-nanometer precision Communications Physics 2(1), 150 (2019) [10.1038/s42005-019-0253-2]   OpenAccess: PDF PDF (PDFA); 2019-11-2112:54 [PUBDB-2019-04354] Book/Report/Dissertation / PhD Thesis Herrmann, C. Ab initio radiation chemistry [DESY-THESIS-2019-029] Hamburg : Verlag Deutsches Elektronen-Synchrotron, DESY-THESIS 119 pp. (2019) [10.3204/PUBDB-2019-04354] = Dissertation, Universität Hamburg, 2019   The development of tools and techniques such as free-electron lasers (FELs) and pumpprobeexperiments has advanced the field of femtochemistry and made it possible tofollow the real-time dynamics of photo-excited molecular species on the femtosecondtime scale. Advances in femtochemistry experiments present new challenges and opportunitiesin the field of theoretical/computational femtochemistry for describing theultrafast molecular dynamics on the potential energy surfaces of electronically excitedmolecules.This thesis presents a series of theoretical studies on ultrafast dynamics of molecularsystems after excitation/ionization by laser pulses in the VUV to XUV regime, whichis highly relevant for pump-probe experiments [...] OpenAccess: Bazi_thesis_for_print - PDF PDF (PDFA); desy-thesis-19-029.title - PDF PDF (PDFA); 2019-10-1714:28 [PUBDB-2019-03705] Journal Article et al Spectroscopic Signature of Chemical Bond Dissociation Revealed by Calculated Core-Electron Spectra The journal of physical chemistry letters 10, 6536 - 6544 (2019) [10.1021/acs.jpclett.9b02370]   The advent of ultrashort soft X-ray pulse sources permits the use of established gas-phase spectroscopy methods to investigate ultrafast photochemistry in isolated molecules with element and site specificity. In the present study, we simulate excited-state wavepacket dynamics of a prototypical process, the ultrafast photodissociation of methyl iodide. [...] Published on 2019-10-07. Available in OpenAccess from 2020-10-07.: PDF PDF (PDFA); Restricted: suppl - PDF PDF (PDFA); acs.jpclett.9b02370 - PDF PDF (PDFA); 2019-10-1612:27 [PUBDB-2019-03690] Journal Article et al Similarity in ruthenium damage induced by photons with different energies: From visible light to hard X-rays Applied surface science 501, 143973 - (2020) [10.1016/j.apsusc.2019.143973]   We performed combined experimental and computational research on damage processes in ruthenium thin films induced by femtosecond lasers with various photon energies. We present an experiment with an optical laser at normal incidence conditions and compare it with previously reported experiments at grazing incidence conditions with XUV and hard X-ray photons, covering a large range of photon energies. [...] OpenAccess: PDF PDF (PDFA); 2019-09-2411:25 [PUBDB-2019-03439] Journal Article et al Femtosecond-resolved observation of the fragmentation of buckminsterfullerene following X-ray multiphoton ionization Nature physics 15, 1279-1283 (2019) [10.1038/s41567-019-0665-7]   Fulltext: PDF PDF (PDFA); 2019-09-0310:01 [PUBDB-2019-03189] Journal Article Welsch, R. Kinetic isotope effects in the water forming reaction $\mathrm{H_{2} /D_{2} +}$ OH from rigorous close-coupling quantum dynamics simulations Physical chemistry, chemical physics 21(31), 17054 - 17062 (2019) [10.1039/C9CP02323B]   Thermal rate constants and kinetic isotope effects (KIE) for the prototypical water-forming $\mathrm{D_2 + OH → D + DHO}$ reaction are calculated for temperatures between 150 K and 1000 K using rigorous quantum dynamics simulations including all degrees of freedom. Very good comparison with experimental results is found for the thermal rate constants and overall good comparison with experimental KIE is obtained. [...] Published on 2019-06-27. Available in OpenAccess from 2020-06-27.: PDF PDF (PDFA); Restricted: PDF PDF (PDFA); 2019-08-2614:15 [PUBDB-2019-03117] Journal Article Santra, R. Ultrafast Charge Transfer and Structural Dynamics Following Outer-Valence Ionization of a Halogen-Bonded Dimer The journal of physical chemistry / A 123(34), 7351 - 7360 (2019) [10.1021/acs.jpca.9b00646]   We study the temporal evolution of the CH$_2$O···ClF halogen-bonded dimer following vertical ionization out of outer-valence molecular orbitals on a femtosecond time scale, employing mixed quantum-classical molecular dynamics simulations. The charge density pattern in the ground state that is suitable for the formation of the ground-state halogen bond can be changed upon ionization. [...] Restricted: PDF PDF (PDFA);