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Use of a fragmentary model in the analysis of the atomic structure of an Al 87 Ni 10 Nd 3 amorphous metal alloy made it possible to determine that it has fragments of the structures of three phases, namely, Al, Al 3 Ni, and Al 3 Nd. After crystallization of the alloy under the action of pulse photon irradiation, polycrystals of pure aluminum and two Al 3 Ni and Al 4 Nd intermetallides were found in it. Because fragments of structure Al 4 Nd were not observed in the amorphous state, it follows that atoms which form fragments structure Al 3 Nd rearrange to structure Al 4 Nd upon crystallization.

The X-ray scattering intensity curves for vitreous As 2 S 3 are experimentally measured using soft (copper) and hard (molybdenum) X rays. The inclusion of all the specific features revealed in the experimental scattering intensity curves makes it possible to obtain the experimental atomic radial distribution function (ARDF) in the ordering range up to ~1 nm. The experimental ARDF is interpreted in the framework of the fragmentary model. A comparison of the experimental ARDF with the model ARDF calculated from the crystal structure data obtained for orpiment demonstrates that the corrugated layers inherent in crystalline As 2 S 3 are retained in the glass structure but the characteristic interlayer interatomic distances are absent. The layers are joined together through the As 4 S 5 molecular clusters. Microcrystals consisting of several unit cells are absent in the glass structure, which involves only the structural fragments of both crystalline analogs. One of the possible variants of their joining is proposed.

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