Glass formation in amorphous SiO2 as a percolation phase transition in a system of network defects

@article{Ojovan2004GlassFI,
  title={Glass formation in amorphous SiO2 as a percolation phase transition in a system of network defects},
  author={Michael I. Ojovan},
  journal={Journal of Experimental and Theoretical Physics Letters},
  year={2004},
  volume={79},
  pages={632-634}
}
  • M. I. Ojovan
  • Published 1 June 2004
  • Materials Science
  • Journal of Experimental and Theoretical Physics Letters
Thermodynamic parameters of defects (presumably, defective SiO molecules) in the network of amorphous SiO2 are obtained by analyzing the viscosity of the melt with the use of the Doremus model. The best agreement between the experimental data on viscosity and the calculations is achieved when the enthalpy and entropy of the defect formation in the amorphous SiO2 network are Hd=220 kJ/mol and Sd=16.13R, respectively. The analysis of the network defect concentration shows that, above the glass… Expand
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