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Updated: Apr 30, 2026

Analyzing Melts and Fluids from Ab Initio Molecular Dynamics Simulations with the UMD Package
Published on: September 17, 2021
Voids in mixed-cation silicate glasses: Studies by positron annihilation lifetime and Fourier transform infrared
M Reben1, E Golis2, J Filipecki2
1AGH-University of Science and Technology, Faculty of Materials Science and Ceramics, Al. Adama Mickiewicza 30, 30-059 Kraków, Poland.
Abstract:
PALS in comparison with FTIR studies have been applied to investigate the structure of different oxide glasses. Three components of the positron lifetime τ (τ1 para- and τ3 ortho-positronium and τ2 intermediate lifetime component) and their intensities were obtained. The results of the calculation of mean values of positron lifetimes for the investigated glasses showed the existence of a long-living component on the positron annihilation lifetime spectra. From the Tao-Eldrup formula we can estimate the size of free volume. On the basis of the measurements we can conclude that the size and fraction of free volume reaches the biggest value for the fused silica glass. The degree of network polymerisation increases void size.
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