Search results for "Effective density"
showing 3 items of 3 documents
ChemInform Abstract: Specific Heat of Amorphous Silica within the Harmonic Approximation.
2010
We 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(ν). We find that the harmonic approximation is valid for temperatures below 300 K but starts to break down at higher temperatures. We show that, to obtain a reliable description of the low-frequency part of g(ν), i.e., where the boson peak is observed, it is essential to use large systems for the simulations and small cooling rates to quench the samples. We find that the calcul…
Specific Heat of Amorphous Silica within the Harmonic Approximation
1999
We 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(ν). We find that the harmonic approximation is valid for temperatures below 300 K but starts to break down at higher temperatures. We show that, to obtain a reliable description of the low-frequency part of g(ν), i.e., where the boson peak is observed, it is essential to use large systems for the simulations and small cooling rates to quench the samples. We find that the calcul…
Multi-technique characterization of gold electroplating on silver substrates for cultural heritage applications
2017
Proceedings of the 12th European Conference on Accelerators in Applied Research and Technology (ECAART12).-- et al.