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Raman thresholds and rigid to floppy transitions in calcium silicate glasses

M. Micoulaut·M. Malki·P. Simon·A. Canizares
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Abstract

Alkaline earth silicate glasses $xCaO-(1-x)SiO_2$ exhibit a well marked threshold in Raman lineshapes which can be related to the onset of network rigidity as the concentration of calcium oxide $x$ is decreased. The present results are analyzed by constraint counting algorithms and more deeply characterized by a size increasing cluster approximation that allows to perform Maxwell mechanical constraint counting beyond the usual mean-field treatment. This permits to discuss under which structural conditions an elastic intermediate phase can be obtained.

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M. Micoulaut, M. Malki, P. Simon, A. Canizares. 2004-10-29. Raman thresholds and rigid to floppy transitions in calcium silicate glasses. https://arxiv.org/abs/cond-mat/0410770

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