The specific heat of amorphous silica within the harmonic approximation

Simple item page
dc.creatorHorbach, Jurgen
dc.creatorKob, Walter
dc.creatorBinder, Kurt
dc.date1998-09-17
dc.date.accessioned2026-07-07T03:11:32Z
dc.date.available2026-07-07T03:11:32Z
dc.descriptionWe investigate to what extent the specific heat of amorphous silica can be calculated within the harmonic approximation. For this we use molecular dynamics computer simulations to calculate, for a simple silica model (the BKS potential), the velocity autocorrelation function and hence an effective density of states g(nu). We find that the harmonic approximation is valid for temperatures below 300K but starts to break down at higher temperatures. We show that in order to get a reliable description of the low frequency part of g(nu), i.e. where the boson peak is observed, it is essential to use large systems for the simulations and small cooling rates with which the samples are quenched. We find that the calculated specific heat is, at low temperatures (below 50K), about a factor of two smaller than the experimental one. In the temperature range 200K <= T <= T_g, where T_g=1450K is the glass transition temperature, we find a very good agreement between the theoretical specific heat and the experimental one.
dc.description9 pages of Latex, 4 figures
dc.identifierhttps://arxiv.org/abs/cond-mat/9809229
dc.identifierhttp://arxiv.org/abs/cond-mat/9809229
dc.identifierJ. Phys. Chem. B 103, 4104 (1999)
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/28607
dc.subjectStatistical Mechanics
dc.subjectDisordered Systems and Neural Networks
dc.titleThe specific heat of amorphous silica within the harmonic approximation
dc.typetext

Files

Collections

arXiv