Structure of Te_1-xCl_x Liquids

摘要

The structure of Te1?xClx. liquids having composition outside the glassy domain has been investigated using neutron diffraction. Te-rich (x = 0.0, 0.1, 0.2, 0.3) and Cl-rich (x = 0.7, 0.8) liquids have been measured just above their respective melting points, 240 °CT490 °C. The neutron structure factor SN(Q) exhibits a pronounced First Sharp Diffraction Peak (FSDP) for the Cl-rich compositions suggesting a significant intermediate range order in these molecular liquids. In contrast, the FSDP appears to be weak for the Te-rich liquid alloys presumably having a chain network structure. As expected, two different nearest-neighbour distances have been found in the total correlation function TN(r). The first peak at r12.4 ?, corresponding to Cl-Te contacts, increases with x. The second at r22.8 ? is related to the Te-Te first neighbours and decreases with x. A detailed analysis of the TN(r) and difference TN(r) is given in the contribution and allows between three possible structural models to be chosen.