The Nature of Oxide Layers on Single Crystals of Cadmium and Magnesium

Abstract

Abstract The oxide layers formed on cadmium and magnesium single crystals on exposure to air at room temperature have been studied by electron diffraction, optical and electron microscopy, and X‐ray topography. A single crystal oxide layer of CdO 2 is formed on cadmium with (111) parallel to (0001) and [1 1 0] parallel to [11 2 0]. For magnesium, the oxide is a textured polycrystalline layer of MgO with an orientation relationship to the metal similar to that for cadmium and its oxide. The oxide layers on both metals are initially adherent but with increasing time of exposure to air, blisters form and cracking of the oxide occurs. The formation of oxide on cadmium produces visible defects within the crystal but no similar defects are observed in magnesium.