High-pressure high-temperature synthesis of NdRe2

Abstract

In this study, we report the synthesis of a new cubic neodymium-rhenium metallic alloy NdRe₂ through the utilization of high pressure and laser heating in a diamond anvil cell. NdRe₂ crystallizes in the $Fd\overline{3}m$ space group with a lattice parameter equal to 7.486 (2) Å and Z = 8 at 24 (1) GPa and 2,200 (100) K. It was studied using high-pressure single-crystal X-ray diffraction. The compound crystallizes in the cubic MgCu₂ structure type. Its successful synthesis further proves that high-pressure high-temperature conditions can be used to obtain alloys holding a Laves phase structure. Ab initio calculations were done to predict the mechanical properties of the material. We also discuss the usage of extreme conditions to synthesize and study materials present in the nuclear waste.

Keywords: crystal structure; diamond anvil cell; high pressure high temperature; laser heating; laves phases; neodymium rhenium; nuclear waste; synthesis.