STRUCTURAL RELATIONS BETWEEN CRYSTALLINE AND GLASSY PHOSPHATES

The common glass definition in middle/extended range order does not reflect the structures of phosphate glasses with polymer structure connection. Based on experimental findings, a new view on this interesting field is given by discussion of order in comparison to crystalline compounds with related composition. Cooperative disorder, which appears in microstates (sort of particles, its orientation, and position) results in changes of the macrostate. The deviation of glass structure from the crystalline order is probably small and seems to be reproducible with given conditions. Therefore, structure sensitive methods can be applied to real structure investigation. In glasses and related crystals the concrete smallest structure pattern is in minimum the same. Phosphate glasses probably consist of two corresponding networks: the nearly temperature independent anionic network of PO4 tetrahedra and the cationic “network”, which influences the structure of the anionic network depending on its sort and number of cations. Above Tg the cations become more mobile and shift their spaces. This process is reversible and reproducible.