Cationic and Anionic Impact on the Electronic Structure of Liquid Water
- Hydration shells around ions are crucial for many fundamental biological and chemical processes. Their local physicochemical properties are quite different from those of bulk water and hard to probe experimentally. We address this problem by combining soft X-ray spectroscopy using a liquid jet and molecular dynamics (MD) simulations together with ab initio electronic structure calculations to elucidate the water ion interaction in a MgCl2 solution at the molecular level. Our results reveal that salt ions mainly affect the electronic properties of water molecules in close vicinity and that the oxygen K-edge X-ray emission spectrum of water molecules in the first solvation shell differs significantly from that of bulk water. Ion-specific effects are identified by fingerprint features in the water X-ray emission spectra. While Mg2+ ions cause a bathochromic shift of the water lone pair orbital, the 3p orbital of the Cl- ions causes an additional peak in the water emission spectrum at around 528 eV.
Author details: | Zhong YinORCiD, Ludger InhesterORCiD, Sreevidya Thekku Veedu, Wilson Quevedo, Annette PietzschORCiD, Philippe WernetORCiD, Gerrit GroenhofORCiD, Alexander FöhlischORCiDGND, Helmut Grubmueller, Simone Techert |
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DOI: | https://doi.org/10.1021/acs.jpclett.7b01392 |
ISSN: | 1948-7185 |
Pubmed ID: | https://pubmed.ncbi.nlm.nih.gov/28742347 |
Title of parent work (English): | The journal of physical chemistry letters |
Publisher: | American Chemical Society |
Place of publishing: | Washington |
Publication type: | Article |
Language: | English |
Year of first publication: | 2017 |
Publication year: | 2017 |
Release date: | 2020/04/20 |
Volume: | 8 |
Number of pages: | 6 |
First page: | 3759 |
Last Page: | 3764 |
Funding institution: | German Science Foundation (DFG) [SFB755, SFB 1073]; Max Planck Institute for Biophysical Chemistry; Deutsches Elektronen-Synchrotron; Helmholtz Virtual Institute "Dynamic Pathways in Multidimensional Landscapes"; Academy of Finland [258806] |
Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Physik und Astronomie |
Peer review: | Referiert |