Raman Spectroscopy of Optical Lattice Vibrations in Small CdS Crystals Embedded in SiO2 Films M. I. Vasilevskiy, A. G. Rolo and M.J.M. Gomes “International Conference on Defects in Semiconductors - ICDS’97”, 21-25 Julho de 1997, Universidade de Aveiro, Aveiro, Portugal