Nucleation in oxide glasses: comparison of theory and experiment

Experimental nucleation rates on eight oxide glasses crystallizing polymorphously are analysed in terms of non-classical nucleation theories, including phenomenological and density functional approaches. It is demonstrated that of the six non-classical models considered here, only the semiempirical density functional approach and the phenomenological diffuse interface theory are fully consistent with the data. The other models (the self-consistent classical theory, the detailed molecular theories and a Ginzburg-Landau/Cahn-Hilliard model) did not provide a satisfactory fit with experiment. The failure/success of these approaches is discussed in terms of the applied approximations.