title: X-ray absorption spectroscopy measurements of liquid water.
abstract: Recent studies, based on X-ray absorption spectroscopy (XAS) and X-ray Raman scattering (XRS), have shown that the hydrogen bond network in liquid water consists mainly of water molecules with only two strong hydrogen bonds. Since this result is controversial, it is important to demonstrate the reliability of the experimental data, which is the purpose of this paper. Here we compare X-ray absorption spectra of liquid water recorded with five very different techniques sensitive to the local environment of the absorbing molecule. Overall, the spectra obtained with photon detection show a very close similarity and even the observable minor differences can be understood. The comparison demonstrates that XAS and XRS can indeed be applied reliably to study the local bonding of the water molecule and thus to reveal the hydrogen bond situation in bulk water.
authors.affiliation: FYSIKUM, Stockholm University, Albanova University Center, S-106 91 Stockholm, Sweden.
authors.forename: L-A
authors.initials: LA
authors.lastname: Näslund
authors.forename: J
authors.initials: J
authors.lastname: Lüning
authors.forename: Y
authors.initials: Y
authors.lastname: Ufuktepe
authors.forename: H
authors.initials: H
authors.lastname: Ogasawara
authors.forename: Ph
authors.initials: P
authors.lastname: Wernet
authors.forename: U
authors.initials: U
authors.lastname: Bergmann
authors.forename: L G M
authors.initials: LG
authors.lastname: Pettersson
authors.forename: A
authors.initials: A
authors.lastname: Nilsson
mesh_terms: D015502:Absorptiometry, Photon / Q000379:methods*; D000042:Absorption; D002627:Chemistry, Physical / Q000379:methods*; D004583:Electrons; D006860:Hydrogen Bonding; D007700:Kinetics; D015233:Models, Statistical; D017785:Photons; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity; D013057:Spectrum Analysis; D013059:Spectrum Analysis, Raman; D014867:Water / Q000737:chemistry*; D014965:X-Rays
chemical_list: D014867:Water