Explanation
with α- Al2O3 represents the main structural type of A2B3 type compounds. It belongs to the tripartite system, and the space group is R3c. Oxygen ions as ABAB Cubically packed, Al3+occupies 2/3 of the oxygen octahedral voids, while the other 1/3 octahedral voids are empty.
Classification
Inorganic non-metallic materials -> Basics of inorganic non-metallic materials