Manifestation of glass-crack fractal geometry in Raman spectra

A Raman spectroscopic investigation of the fractal structure on the surface of cracks of different size scales in glassy SiO2 is reported. A study was made of the crack surface and of the distorted layer formed after grinding and polishing and comminution. The parameters of the fractal structure thu s found reflect the properties of the material and the crack nature; namely , fractal dimension is of greater importance for more compact materials, an d the geometric size of fractal units (i.e., the size in real space) correl ates with crack dimensions. (C) 1999 American Institute of Physics. [S1063- 7834(99)02206-6].