FLUCTUATIONS AND NONCONTINUOUS NETWORK IN DISORDERED-SYSTEMS - LOW-FREQUENCY RAMAN-SCATTERING

The frequency dependence of the light-vibration coupling coefficient i s related to the random fluctuations of the vibrations in disordered s ystems. The disorder is described by differentiating between the radia l correlation and the angular correlation. It is shown that the behavi our of gels is different from that of glasses. If there exists only ra dial correlation in glasses, the angular correlation is also present i n gels. The effect of quenching on the low-frequency Raman scattering of polymethylmethacrylate is compared with the increase in free volume by heating, observed by other workers, to improve the model of the no n-continuous network of glasses.