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Percolative conductivity in alkaline earth silicate melts and glasses

M. Malki·M. Micoulaut·F. Chaimbault·Y. Vaills·P. Simon
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Abstract

Ion conducting $(CaO)_x(SiO_2)_{1-x}$ glasses and melts show a threshold behaviour in dc conductivity near $x=x_t=0.50$, with conductivities increasing linearly at $x>x_t$. We show that the behaviour can be traced to a rigid ($x<0.50$) to floppy ($x>0.50$) elastic phase transition near $x=x_t$. In the floppy phase, conductivity enhancement is traced to increased mobility or diffusion of $Ca^{2+}$ carriers as the modified network elastically softens.

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M. Malki, M. Micoulaut, F. Chaimbault, Y. Vaills, P. Simon. 2003-10-28. Percolative conductivity in alkaline earth silicate melts and glasses. https://doi.org/10.1209/epl%2Fi2003-00278-2

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