Raman thresholds and rigid to floppy transitions in calcium silicate glasses
arXiv:cond-mat/0410770
Abstract
Alkaline earth silicate glasses exhibit a well marked threshold in Raman lineshapes which can be related to the onset of network rigidity as the concentration of calcium oxide 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.
11 pages, 12 figures