X-RAY AND NEUTRON-DIFFRACTION IN STRUCTURAL-GLASS PHASES OF CRYSTALLINE SOLID-SOLUTIONS

The x-ray and neutron diffraction in structural-glass phases of crysta lline solid solutions is considered in the framework of the quasidomai n model of the atomic structure of glass phases. The model presumes th at the solid solutions in such phases consist of a number of macroscop ic quasidomains with nearly homogeneous random deformations. The gener al expressions for the intensities and widths of quasi-Bragg scatterin g for various types of diffraction experiments are obtained for the co ntinuous glass transitions in terms of the matrix of mean-square rando m deformations S-mn and average sizes of quasidomains. The relation of the S-mn form to the symmetry of the crystal in the high-temperature phase and the type of glass transition is established. The general res ults are illustrated on examples of diffraction in glass phases of cub ic and hexagonal crystals.