Compatibility of quantitative X-ray spectroscopy with continuous distribution models of water at ambient conditionsShow others and affiliations
2019 (English)In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 116, no 10, p. 4058-4063Article in journal (Refereed) Published
Abstract [en]
The phase diagram of water harbors controversial views on underlying structural properties of its constituting molecular moieties, its fluctuating hydrogen-bonding network, as well as pair-correlation functions. In this work, long energy-range detection of the X-ray absorption allows us to unambiguously calibrate the spectra for water gas, liquid, and ice by the experimental atomic ionization cross-section. In liquid water, we extract the mean value of 1.74 +/- 2.1% donated and accepted hydrogen bonds per molecule, pointing to a continuous-distribution model. In addition, resonant inelastic X-ray scattering with unprecedented energy resolution also supports continuous distribution of molecular neighborhoods within liquid water, as do X-ray emission spectra once the femtosecond scattering duration and proton dynamics in resonant X-ray-matter interaction are taken into account. Thus, X-ray spectra of liquid water in ambient conditions can be understood without a two-structure model, whereas the occurrence of nanoscale-length correlations within the continuous distribution remains open.
Place, publisher, year, edition, pages
NATL ACAD SCIENCES , 2019. Vol. 116, no 10, p. 4058-4063
Keywords [en]
structure of water, X-ray spectroscopy, continuous distribution model
National Category
Chemical Sciences
Identifiers
URN: urn:nbn:se:kth:diva-247814DOI: 10.1073/pnas.1815701116ISI: 000460242100026PubMedID: 30782822Scopus ID: 2-s2.0-85062462267OAI: oai:DiVA.org:kth-247814DiVA, id: diva2:1299494
Note
QC 20190327
2019-03-272019-03-272022-06-26Bibliographically approved