. What is Spinel and Inverse Spinel Structure
Spinel is a mineral (MgAl2O4). Generally they can be represented as M2+M23+O4, where M2+ is present in one-eighth of tetrahedral voids in a FCC lattice of oxide ions and M3+ions are present in half of the octahedral voids. M2+ is usually Mg, Fe, Co, Ni, Zn and Mn; M3+ is generally Al, Fe, Mn, Cr and Rh. Examples are ZnAl2O4, Fe3O4, FeCr2O4 etc. Many substances of the type also have this structure. In an inverse spinel the ccp is of oxide ions, M2+ is in one-eight of the tetrahedral voids while M3+ would be in one-eight of the tetrahedral voids and one-fourth of the octahedral voids.