Local structure in liquid Hg–Rb alloys studied by EXAFS

The local structures around Hg and Rb atoms in liquid Hg-Rb alloys have been studied by extended X-ray absorption fine structure (EXAFS) measurements. The EXAFS spectra were obtained for Rb K-, Hg L 1 - and Hg L 111 -edges as a function of composition. The average distances for Rb-Hg and Hg-Hg obtained by simple model fitting are comparable to the values found in the solid Hg 19 Rb 5 crystalline compound, which form Hg n (n = 4 or 5) units around a Rb atom. Based on these results, the anomalous behavior on the electronic properties of liquid Hg-alkali alloys, such as the maximum of the electrical resistivity at 60 at.% alkali, is discussed.