Structure of the Molten 37 a/o Cu-63 a/o Sb Alloy Using the Isotopic Substitution Method in Neutron Diffraction

A neutron diffraction study o f the eutectic Cu-Sb-melt containing 37 a/o Cu has been performed using isotopically enriched samples. The three partial structure factors describing the Cu-Cu, Cu-Sb, and Sb-Sb correlations have been determined as well as a second set of partial structure factors relating to the distance correlation o f fluctuations in number density and concentration. Unsmoothed total structure factors were used. B y Fourier-transformation the corresponding pair correlation functions were obtained. A strong segregation tendency was found. Concentration fluctuations with a correlation length o f 2.4 Ä could be determined. From the Fourier-transform o f S e c the product A7 iai was obtained confirming the segregation tendency. The distance o f nearest Cu-Cu neighbours in the eutectic Cu-Sb melt was found to be smaller than in pure molten Cu, whereas the Sb-Sb distance is larger than in pure Sb. According to Faber-Ziman theory the electrical resistivity was calculated and compared with experimental data.