# CFEL-DESYT

 2018-09-1712:23 [PUBDB-2018-03517] Journal Article et al Hard X-ray induced fast secondary electron cascading processes in solids Applied physics letters 113(11), 114102 (2018) [10.1063/1.5046070]   Recent studies confirmed that the materials used in the extreme UV and soft X-ray regime for precise characterization of intense free-electron laser pulses (e.g., Si$_3$N$_4$) do not work efficiently in the hard X-ray regime, which is due to the fact that the impact of a hard X-ray photon is followed by a series of electron cascading processes. Following theoretical indication, we show that this limitation can be circumvented and the cascading time can be significantly reduced if the X-ray photon energy is double the ionization energy [...] Restricted: PDF PDF (PDFA); 2018-08-2709:42 [PUBDB-2018-03176] Journal Article et al Various damage mechanisms in carbon and silicon materials under femtosecond X-ray irradiation 4Open 1, 3 (2018) [10.1051/fopen/2018003]   We review the results of our research on damage mechanisms in materials irradiated with femtosecond free-electron-laser (FEL) pulses. They were obtained using our hybrid approach, X-ray-induced thermal and non-thermal transitions (XTANT) [...] OpenAccess: PDF PDF (PDFA); 2018-08-1710:46 [PUBDB-2018-02994] Journal Article et al Ab initio calculation of electron-impact-ionization cross sections for ions in exotic electron configurations Physical review / A 98(2), 022701 (2018) [10.1103/PhysRevA.98.022701]   Atomic or molecular assemblies irradiated with intense hard x-ray pulses, such as those emitted from x-ray free-electron lasers (XFELs), are subject to a strong ionization, which also releases electrons from atomic inner shells. The resulting core-hole states relax via various channels, including fluorescence and Auger decay [...] OpenAccess: PDF PDF (PDFA); 2018-08-0718:46 [PUBDB-2018-02847] Dissertation / PhD Thesis Santra, R. Transient optical properties as a signature of structural changes within FEL irradiated solids 137 pp. (2017) [10.3204/PUBDB-2018-02847] = Dissertation, University of Hamburg, 2017   OpenAccess: PDF PDF (PDFA); 2018-06-1411:07 [PUBDB-2018-02269] Journal Article et al Prospects of Using High-Intensity THz Pulses To Induce Ultrafast Temperature-Jumps in Liquid Water The journal of physical chemistry / A 122(23), 5211 - 5222 (2018) [10.1021/acs.jpca.8b00828]   Ultrashort, high-intensity terahertz (THz) pulses, e.g., generated at free-electron laser facilities, allow for direct investigation as well as the driving of intermolecular modes in liquids like water and thus will deepen our understanding of the hydrogen bonding network. In this work, the temperature-jump (T-jump) of water induced by THz radiation is simulated for ten different THz frequencies in the range from 3 to 30 THz and five different pulse intensities in the range from 1 × 10$^{11}$ to 5 × 10$^{12}$ W/cm$^{2}$ employing both ab initio molecular dynamics (AIMD) and force field molecular dynamics (FFMD) approaches. [...] Restricted: PDF PDF (PDFA); 2018-06-0411:23 [PUBDB-2018-02173] Journal Article et al Radiation-Induced Chemical Dynamics in Ar Clusters Exposed to Strong X-Ray Pulses Physical review letters 120(22), 223201 (2018) [10.1103/PhysRevLett.120.223201]   We show that electron and ion spectroscopy reveals the details of the oligomer formation in Ar clusters exposed to an x-ray free electron laser (XFEL) pulse, i.e., chemical dynamics triggered by x rays. With guidance from a dedicated molecular dynamics simulation tool, we find that van der Waals bonding, the oligomer formation mechanism, and charge transfer among the cluster constituents significantly affect ionization dynamics induced by an XFEL pulse of moderate fluence [...] OpenAccess: PDF PDF (PDFA); 2018-05-3114:00 [PUBDB-2018-02163] Journal Article Welsch, R. Rigorous close-coupling quantum dynamics calculation of thermal rate constants for the water formation reaction of H$_2$ + OH on a high-level PES The journal of chemical physics 148(20), 204304 - (2018) [10.1063/1.5033358]   Thermal rate constants for the prototypical H$_2$ + OH → H + H$_2$O reaction are calculated using quantum dynamics simulations including all degrees of freedom and accurately accounting for overall rotation via close-coupling. Results are reported for a recent, highly accurate neural network potential [J [...] OpenAccess: PDF PDF (PDFA); 2018-05-3110:11 [PUBDB-2018-02152] Journal Article et al Molecular polarizability anisotropy of liquid water revealed by terahertz-induced transient orientation Nature Communications 9(1), 2142 (2018) [10.1038/s41467-018-04481-5]   Reaction pathways of biochemical processes are influenced by the dissipative electrostatic interaction of the reagents with solvent water molecules. The simulation of these interactions requires a parametrization of the permanent and induced dipole moments. [...] OpenAccess: PDF PDF (PDFA); 2018-05-3009:55 [PUBDB-2018-02139] Journal Article et al Electron and fluorescence spectra of a water molecule irradiated by an x-ray free-electron laser pulse Physical review / A 97(5), 053415 (2018) [10.1103/PhysRevA.97.053415]   With the highly intense x-ray light generated by x-ray free-electron lasers (XFELs), molecular samples can be ionized many times in a single pulse. Here we report on a computational study of molecular spectroscopy at the high x-ray intensity provided by XFELs [...] OpenAccess: PDF PDF (PDFA); 2018-05-0917:57 [DESY-THESIS-2018-014] Book/Report/Dissertation / PhD Thesis Santra, R. A simulation framework for studying high intensity x-ray induced dynamics and scattering patterns from nanocrystals [DESY-THESIS-2018-014] Hamburg : Verlag Deutsches Elektronen-Synchrotron, DESY-THESIS 121 pp. (2018) [10.3204/PUBDB-2018-01938] = Dissertation, Universität Hamburg, 2017   A standard method of reconstructing the structure of a protein in its crystalline phase is by x-ray diffraction. New generation x-ray sources, the X-ray free-electron lasers (XFEL), provide novel opportunities for biomolecular structure determination. [...] OpenAccess: Thesis Pdf - PDF; desy-thesis-18-014.title - PDF PDF (PDFA);