Damping of vibrational excitations in glasses at terahertz frequency: The case of 3-methylpentane
| Autor: | P. Benassi, Flavio Rossi, Aldo Fontana, Andrea Giugni, Michele Nardone, Giulio Monaco, Giacomo Baldi |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
Diffraction
X ray scattering First sharp diffraction peak Inelastic x-ray scattering Longitudinal modes Low-frequency Raman Raman Scattering measurements Static structure factors Terahertz frequencies Vibrational excitation Glass X ray scattering General Physics and Astronomy Terahertz frequencies 02 engineering and technology 01 natural sciences Low-frequency Raman Longitudinal mode symbols.namesake Physics and Astronomy (all) Vibrational excitation 0103 physical sciences Physical and Theoretical Chemistry 010306 general physics Physics Condensed matter physics Scattering Static structure factors First sharp diffraction peak Raman Scattering measurements Inelastic x-ray scattering Longitudinal modes Glass 021001 nanoscience & nanotechnology Transverse mode Molecular vibration symbols 0210 nano-technology Raman spectroscopy Structure factor Raman scattering |
| Popis: | We report a compared analysis of inelastic X ray scattering (IXS) and of low frequency Raman data of glassy 3-methylpentane. The IXS spectra have been analysed allowing for the existence of two distinct excitations at each scattering wavevector obtaining a consistent interpretation of the spectra. In particular, this procedure allows us to interpret the linewidth of the modes in terms of a simple model which relates them to the width of the first sharp diffraction peak in the static structure factor. In this model, the width of the modes arises from the blurring of the dispersion curves which increases approaching the boundary of the first pseudo-Brillouin zone. The position of the boson peak contribution to the density of vibrational states derived from the Raman scattering measurements is in agreement with the interpretation of the two excitations in terms of a longitudinal mode and a transverse mode, the latter being a result of the mixed character of the transverse modes away from the center of the pseudo-Brillouin zone. |
| Databáze: | OpenAIRE |
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