Structure of undercooled liquid Pd probed by X-ray absorption spectroscopy

We report x-ray absorption spectra of high temperature solid Pd at 1770 K, liquid Pd at 1850 K, and undercooled liquid Pd at 1770 and 1670 K (about 160 K below T-m = 1827 K). Data of excellent quality were collected at the European Synchrotron Radiation Facility using an experimental setup combining x-ray absorption spectroscopy, x-ray absorption temperature scans, and x-ray diffraction. The data have been interpreted using an advanced data-analysis method leading to the reliable determination of the radial distribution function g(r) up to r approximate to 3 Angstrom. The structural differences between undercooled liquid Pd and the liquid in thermodynamic equilibrium are discussed.