Sébastien Clément | Searcharxiv

arXiv2024

Electronic interactions of a new quatertiophene-based surfactants atliquid/gas interface

We report the synthesis of a new functional molecule, a quater-tiophene based surfactant, which can both adsorb at the water / gas interface (surface active molecule) and aggregates through pi-pi stacking interactions. We assess then the ability of this molecule to create these functionalities at interfaces. This interfacial functional aggregation, characterized here in situ for the first time, is probed thanks to Langmuir trough experiments and spectrometric ellipsometry. These results open some new routes for the design of new water based opto-electronic devices.

cond-mat.soft↗

arXiv2019

Pressure-induced densification of vitreous silica: insight from elastic properties

\textit{In situ} high-pressure Brillouin light scattering experiments along loading-unloading paths are used to investigate the compressibility of vitreous silica. An accurate equation of state is obtained below \SI{9}{GPa} using sound velocities corrected for dispersion. Conversely, huge inelastic effects are observed in the range \SIrange{10}{60}{GPa}, unveiling the reversible transformation from the fourfold-coordinated structure to the sixfold one. We find that the associated density changes fully correlate with the average Si coordination number. Decompression curves from above \SI{20}{GPa} reveal abrupt backward coordination changes around \SIrange{10}{15}{GPa} and significant hysteresis. Further, contrary to common wisdom, the residual densification of recovered silica samples can be figured out from the pressure cycles.

cond-mat.mtrl-sci↗