The Crystal Structures of Argon and Its Alloys

Abstract

Solid argon is stable in the face-centered cubic structure at all temperatures, but it is found that it can also crystallize in a metastable form with hexagonal close-packed structure.1 Plastic deformation introduces many stacking faults, particularly in the hcp phase, and eventually reduces samples to faulted fcc structure. Small amounts of nitrogen, oxygen, or CO stabilize the hcp phase at temperatures near the melting point.