Growth and crystal structures of solid xenon and krypton

Abstract

A study is reported of the growth and crystal structures of vapor-phase grown polycrystalline samples of xenon and krypton. X-ray diffractometry and powder photography establish that two structures (the well known fcc and the recently discovered hcp phases) co-exist over a large temperature range and under various conditions of growth. Microscopic investigation reveals surface features such as parallel striations and etch pits. The results indicate that fcc is the stable phase of these solids, whereas hcp is metastable. A possible model of growth is described.