Structure of liquid equiatomic potassium-lead alloy: A neutron diffraction experiment

Abstract

Neutron diffraction measurements have been performed on liquid equiatomic potassium-lead alloy at T = 870, 900, and 930 K to determine the influence of temperature on the structure. A well-defined first sharp diffraction peak (FSDP) at Q = 0.96 Å-1, similar to that found in glassy materials, was obtained in the total structure factors S(Q) at the three temperatures. While the position of the peak remained unaffected by temperature changes, its magnitude decreased with increasing temperature. The other features of S(Q) were almost unaltered by temperature, as expected. The FSDP can be related to the presence of chemical bonds or clusters whose stability decreases with increasing temperature. A molecular model based on the random packing of K 4Pb4 structural units is shown to give a remarkable correspondence with the measured structure factors. © 1987 American Institute of Physics.