Year: 2025
Type: article
Abstract: The microscopic structure of water's surface is crucial to many natural and industrial processes, but studying its hydrogen bond (H-bond) network directly remains challenging due to the required interfacial sensitivity of experimental techniques. By leveraging advances in flat liquid sheet microjets and terawatt-scale attosecond soft X-ray pulses from the LCLS X-ray free electron laser, we employed soft X-ray second harmonic generation (SXSHG) spectroscopy to examine the liquid water/vapor interface. SXSHG combines the elemental selectivity of X-ray spectroscopies with the surface selectivity of SHG and gives access to the electronic structure of interfacial species. Here, we show the SXSHG spectrum differs from bulk water's X-ray absorption, with its peak shifted several eV, indicating a vastly different electronic environment at the interface as compared to the bulk. First-principles electronic structure calculations show the signal is highly sensitive to H-bond interactions, such as water molecules accepting a single H-bond, which are surface abundant.
Source: Nature Communications
Authors: David J. Hoffman, Shane W. Devlin, Douglas Garratt, Sasawat Jamnuch, Jacob A. Spies, Bailey R. Nebgen, Daniel Schacher, Alexandria Do, Franky Bernal, Erika J. Riffe, Kristjan Kunnus, Christina Y. Hampton, Joseph Duris, David Cesar, Nicholas Sudar, Georgi L. Dakovski, Walter S. Drisdell, Keith V. Lawler, Agostino Marinelli, Michael W. Zuerch, Richard J. Saykally, Craig P. Schwartz, Tod A. Pascal, Jake D. Koralek
Institutions: SLAC National Accelerator Laboratory, University of Nevada, Las Vegas, Lawrence Berkeley National Laboratory, Advanced Light Source, University of California, Berkeley, National Institute of Standards and Technology, Theiss Research, Material Measurement Laboratory, University of California San Diego
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $6,990
Funders: National Science Foundation, U.S. Department of Energy, U.S. Department of Commerce, National Energy Research Scientific Computing Center, National Institute of Standards and Technology, Office of Science, Office of the President, University of California, Division of Materials Research, Office of Advanced Cyberinfrastructure, Basic Energy Sciences, Chemical Sciences, Geosciences, and Biosciences Division, Lawrence Berkeley National Laboratory, SLAC National Accelerator Laboratory
Awards: G1079818582, G1143651532, G122673668, G1229526393, G1286236842, G1286251239, G1451874870, G1453181110, G1677143136, G1863003419, Track 4: Advanced CI Coordination Ecosystem: Monitoring and Measurement Services, G2037563265, G2371548206, G2618837358, G262532246, Graduate Research Fellowship Program (GRFP), G300518973, G303061748, G30714459, G3083819904, G3265821332, G3406661761, G3562386289, G3714079946, The California Interfacial Science Initiative (CISI), G3884951186, G3898241218, G3927959030, G3946991323, G3993056153, Track 1: ACCESS Resource Allocations Marketplace and Platform Services (RAMPS), G4010157413, G419881185, G4211246138, G4235786860, G42916606, G4361631179, G4478963120, G4501827968, G4654690619, ACO: An Open CI Ecosystem to Advance Scientific Discovery (OpenCI), G495301720, G498139845, PURPOSE: THE PURPOSE OF THIS GRANT IS TO IMPROVE THE SPEED OF SIMULATIONS OF X-RAY SPECTRA AND VALIDATE THEIR ACCURACY FOR SUPPORTING MEASUREMENTS OF CATALYSTS FOR CO2 CONVERSION.ACTIVITIES TO BE PERFORMED: THE RESEARCHER WILL IMPLEMENT NEW, MORE EFFICIENT METHODS WITHIN THE OCEAN X-RAY CODE, FOCUSING ON REDUCING THE AMOUNT OF EFFORT NEEDED FOR THE DENSITY-FUNCTIONAL THEORY CALCULATION THROUGH INTERPOLATION. THE RESEARCHER WILL VALIDATE THESE IMPROVEMENTS THROUGH CAREFUL COMPARISON WITH EXPERIMENTAL X-RAY SPECTRA OF WELL-CHARACTERIZED CATALYSTS. THE VALIDATED IMPROVEMENTS WILL BE APPLIED TO STUDYING SHORT-LIVED INTERMEDIATE STATES FOUND DURING CATALYSIS. EXPECTED OUTCOMES: THE IMPROVEMENTS WILL BE INCORPORATED INTO THE NIST SPECTROSCOPY CODE OCEAN. NOVEL FINDINGS WILL BE REPORTED IN APPROPRIATE JOURNAL ARTICLES.INTENDED BENEFICIARIES: THE IMPROVED CODE WILL BE USED BY EXTERNAL AND INTERNAL USERS OF THE NIST X-RAY BEAMLINES. THE IMPROVEMENTS CAN ALSO BE USED BY RESEARCHERS WORKING ON OTHER SPECTROSCOPY CODES.SUBRECIPIENT ACTIVITIES: THE RECIPIENT DOES NOT INTEND TO SUBAWARD FUNDS., G5076365615, Track 3: COre National Ecosystem for CyberinfrasTructure (CONECT), G5098925467, G512830357, G5212984984, G5218879237, G5338786287, G5367127336, G5464919783, G5570207115, G5995351298, G6025207788, G6121277264, G6247045938, G6473820372, G650090426, G6550344761, G6652958823, G6965887028, G7168589519, G7283024673, G7331630580, G7354628648, G754761654, G8174472116, Track 2: Customized Multi-tier Assistance, Training, and Computational Help (MATCH) for End User ACCESS to CI, G8350824777, G8382000481, G911061179, G969889393
OpenAlex ID: W4416720700