Low Frequency Raman Spectra of Silica Aerogels with Double Fractal Structure

Abstract

Silica aerogel samples with double fractal structure were synthesized. The samples were sintered at 1000 C in different time intervals. In low frequency Raman spectra of the sintered samples, we observed two fractons caused by localization of vibration on clusters of two fractal substructures. During sintering the two fractal substructures become dense and, after 16 h of sintering, merge one into another.