Spinel, MgAl2O4 (download cif), is a rare gemstone that was used to imitate rubies. The structure has face-centered cubic symmetry, and is a little heavy to understand. The general formula is AB2O4. The oxygens form an fcc lattice. The A cations occupy tetrahedral holes, and the B cation occupy octahedral holes.
What is meant by spinel structure?
The spinel structure is a common crystal structure of the AB type composition 2O4 where A is a cation on a tetrahedral site (surrounded by 4 oxygens) and B, two cations on octahedral sites (surrounded by de 6 oxygens).
What are spinels give an example?
EXAMPLES FOR SPINEL AND INVERSE SPINEL STRUCTURES
1) MgAl2O4 has normal spinel structure since both the divalent and trivalent ions are non transition metal ions. There is no question of CFSE. 2) Mn3O4 is a normal spinel since the Mn2+ ion is a high spin d5 system with zero LFSE. ... 6) Co3O4 is a normal spinel.
