LOCAL ORDER HYPOTHESES AND SPATIAL MODEL IN THE GLASSY ALLOY AG0.08AS0.26SE0.66

The radial atomic distribution of the amorphous alloy Ag0.08As0.26Se0. 66 was studied, through the X-ray diffraction data supplied by samples obtained through quenching. The short-range order was determined by i nterpreting the Radial Distribution Function (RDF), using a theoretica l expression which takes into account the variation in the atomic scat tering factors with s (the scattering vector module), and approximates them to polynomic functions. The tetra- and tree-coordinated silver h ypotheses, quoted in the literature for glassy alloys containing this element, were considered. The result of the study is that, for the all oy in question, only the tetra-coordinated silver hypothesis is compat ible with the structural information that was experimentally obtained. A spatial atomic distribution model was generated according to this s ilver coordination, using the conveniently modified Monte Carlo random method. A comparative analysis of the main structural parameters of t his model revealed their good agreement with the values given in the l iterature for similar alloys.