NEUTRON-DIFFRACTION STUDY OF LIQUID TL-SE ALLOYS

A neutron diffraction study on the liquid Tl-Se system has been carried out over the whole concentration range. Profiles of the total structure factors or the pair distribution functions are essentially similar to those of pure liquid Tl up to 66.7 at.% Tl content, suggesting that there forms a certain short range order in the liquid state which is not far from the structure in the sense of short range scale of the pure liquid Tl. The existence of covalent-type Se polymeric structure is confirmed in Se-rich composition range. We have also derived the partial structure factors, using three different total structure factors in a small concentration range, where the partial structure factors were assumed to be constant.