PROBABILITY MODEL FOR RELAXATION

A model for relaxation is suggested. Relaxation is regarded as a rando m process. In complex systems, the relaxation function is no longer ex pressed as a superposition of simple Debye exponential form. Applying the central limit theorem, the ''conventional'' Debye form and the ''a nomalous'' Kohlrausch form of the relaxation function are replaced by the complementary error function. As a test for the model, we have stu died the temperature dependence of the mechanical internal friction sp ectra for different frequencies, the light-scattering relaxation funct ions, and the compressibility relaxation curves of vitreous and molten B2O3. It is particularly noteworthy in these calculations that the te mperature dependence of the two parameters in the relaxation function are given by analytical expressions based on ab initio calculations to B2O3 rather than by fitting only. All these theoretical results are i n good quantitative agreement with available experimental data.