Lattice dynamics of α-cristobalite and the Boson peak in silica glass

Abstract

The lattice dynamics of the silica polymorph α-cristobalite has been investigated by a combination of diffuse and inelastic x-ray scattering and ab initio lattice dynamics calculations. Phonon dispersion relations and vibrational density of states are reported and the phonon eigenvectors analysed by a detailed comparison of scattering intensities. The experimentally validated calculation is used to identify the vibration contributing most to the first peak in the density of vibrational states. The comparison of its displacement pattern to the silica polymorphs α-quartz and coesite and to vitreous silica reveals a distinct similarity and allows for decisive conclusions on the vibrations causing the so-called Boson peak in silica glass.

References in corpus (3)

• Accuracy of generalized gradient approximation functionals for density functional perturbation theory calculations
• Structural stability and lattice dynamics of SiO2 cristobalite
• Lattice dynamics of coesite

Cited by in corpus (4)

• Lattice thermal conductivities of two SiO${}_2$ polymorphs by first-principles calculation and phonon Boltzmann transport equation
• Mechanisms of temperature-dependent thermal transport in amorphous silica from machine-learning molecular dynamics
• Surface phonon induced rotational dissipation for nanoscale solid-state gears
• Phonon propagation scale and nanoscale order in vitreous silica from Raman spectroscopy