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• An impact of the hydrophilic wetting on solid phonon dynamics is revealed by IXS. • Twofold impact: a depth-dependent hardening of acoustic phonons and an internal stress relaxation. • Therefore, a dynamic liquid/solid coupling is revealed, echoing mesoscopic liquid shear elasticity. We examine the influence at room temperature of the deposit of a water layer on the phonon dynamics of a solid. It is shown that the water wetting at the surface of an Alumina monocrystal has deep effects on acoustic phonons, propagating over several hundred µm distance and taking place on a relatively long time scale. The effect of the wetting at the boundary is two-fold: a hardening of both transverse and longitudinal acoustic phonons is observed as well as a relaxation of internal stresses. These acoustic phonon energy changes were observed by inelastic X-ray scattering up to 40 meV energy loss, allowing us to probe the solid at different depths from the surface. [ABSTRACT FROM AUTHOR]

• An impact of the hydrophilic wetting on solid phonon dynamics is revealed by IXS. • Twofold impact: a depth-dependent hardening of acoustic phonons and an internal stress relaxation. • Therefore, a dynamic liquid/solid coupling is revealed, echoing mesoscopic liquid shear elasticity. We examine the influence at room temperature of the deposit of a water layer on the phonon dynamics of a solid. It is shown that the water wetting at the surface of an Alumina monocrystal has deep effects on acoustic phonons, propagating over several hundred µm distance and taking place on a relatively long time scale. The effect of the wetting at the boundary is two-fold: a hardening of both transverse and longitudinal acoustic phonons is observed as well as a relaxation of internal stresses. These acoustic phonon energy changes were observed by inelastic X-ray scattering up to 40 meV energy loss, allowing us to probe the solid at different depths from the surface. [ABSTRACT FROM AUTHOR]

Detecting and quantifying non-bridging oxygen (NBO) atoms is of particular interest for understanding the physical properties of melts or compressed materials, and requires an unequivocal spectral signature usable during in situ measurements. In this paper, we evidence a low-energy feature of NBO in lithium silicate crystals using X-ray Raman scattering (XRS) spectroscopy around the energy losses of the oxygen K -edge. A specific peak at 534–535 eV in the edge onset is unequivocally attributed to the presence of NBO. Its intensity is used to quantify NBO in lithium silicate glasses. A similar feature at low energy has also been evidenced in Na 2 SiO 3 and MgSiO 3 , generalizing the method to other alkali and alkali-earth silicates. This non-destructive method of NBO quantification, which is based on an X-ray inelastic scattering technique, can be extended to other spectroscopies such as electron-energy loss spectroscopy, and soft X-ray absorption spectroscopy at the oxygen K edge. [ABSTRACT FROM AUTHOR]