Cadmium under high pressure and high temperature conditions

Abstract

In this work liquid and solid cadmium has been investigated in a wide pressure and temperature range in order to provide new information about structure and transitions occurring in this metal. X-ray absorption, single-energy temperature scans and energy scanning x-ray diffraction data were collected in a 25–600 °C temperature and 0–5.8 GPa pressure range, exploiting the setup available at the ESRF-BM29 beam-line. Clear changes in the absorption spectra (measured at cadmium K-edge) and in the diffraction patterns, associated with the solid-liquid transition, allowed us to obtain an accurate measurement of the melting curve as a function of pressure. The structural data are compared with the few available calculations and x-ray scattering data on molten Cd at ambient pressure. High pressure data on liquid cadmium are reported for the first time and are essential to shed some light on the changes of the local structure induced by pressure.