TY - JOUR A1 - Pietzsch, Annette A1 - Hennies, Franz A1 - Miedema, Piter S. A1 - Kennedy, Brian A1 - Schlappa, Justine A1 - Schmitt, Thorsten A1 - Strocov, Vladimir N. A1 - Föhlisch, Alexander T1 - Snapshots of the Fluctuating Hydrogen Bond Network in Liquid Water on the Sub-Femtosecond Timescale with Vibrational Resonant Inelastic x-ray Scattering JF - Physical review letters N2 - Liquid water molecules interact strongly with each other, forming a fluctuating hydrogen bond network and thereby giving rise to the anomalous phase diagram of liquid water. Consequently, symmetric and asymmetric water molecules have been found in the picosecond time average with IR and optical Raman spectroscopy. With subnatural linewidth resonant inelastic x-ray scattering (RIXS) at vibrational resolution, we take sub-femtosecond snapshots of the electronic and structural properties of water molecules in the hydrogen bond network. We derive a strong dominance of nonsymmetric molecules in liquid water in contrast to the gas phase on the sub-femtosecond timescale of RIXS and determine the fraction of highly asymmetrically distorted molecules. Y1 - 2015 U6 - https://doi.org/10.1103/PhysRevLett.114.088302 SN - 0031-9007 SN - 1079-7114 VL - 114 IS - 8 PB - American Physical Society CY - College Park ER - TY - JOUR A1 - Rubensson, Jan-Erik A1 - Soderstrom, Johan A1 - Binggeli, Christian A1 - Grasjo, Joakim A1 - Andersson, Johan A1 - Sathe, Conny A1 - Hennies, Franz A1 - Bisogni, Valentina A1 - Huang, Yaobo A1 - Olalde, Paul A1 - Schmitt, Thorsten A1 - Strocov, Vladimir N. A1 - Föhlisch, Alexander A1 - Kennedy, Brian A1 - Pietzsch, Annette T1 - Rydberg-Resolved Resonant Inelastic Soft X-Ray Scattering: Dynamics at Core Ionization Thresholds JF - Physical review letters N2 - Resonant inelastic x-ray scattering spectra excited in the immediate vicinity of the core-level ionization thresholds of N-2 have been recorded. Final states of well-resolved symmetry-selected Rydberg series converging to valence-level ionization thresholds with vibrational excitations are observed. The results are well described by a quasi-two-step model which assumes that the excited electron is unaffected by the radiative decay. This threshold dynamics simplifies the interpretation of resonant inelastic x-ray scattering spectra considerably and facilitates characterization of low-energy excited final states in molecular systems. Y1 - 2015 U6 - https://doi.org/10.1103/PhysRevLett.114.133001 SN - 0031-9007 SN - 1079-7114 VL - 114 IS - 13 PB - American Physical Society CY - College Park ER -