| Structure & lattice | Anions and cations | Coordination number | Examples |
Rock salt (face centered cubic) Example NaCl | Anions in Cubic closed packing.
Cations in Octahedral holes | Coordination number of anions is 6(1 anion is surrounded by 6 cations)
Coordination number of cations is 6(1 cation is surrounded by 6 anion)
6:6 (octahedral)
| All sodium and Pottasium halides
Very common (inc. 'ionics', 'covalents' & 'intermetallics' ) Most alkali halides (CsCl, CsBr, CsI excepted) Most oxides / chalcogenides of alkaline earths Many nitrides, carbides, hydrides (e.g. ZrN, TiC, NaH) |
| Flourite(face centered cubic) Example CaF2 | Cations in CCP Anions in all Tetrahedral holes | Coordination number of cations is 8, anions is 4 | Ca F2
Fluorides of large divalent cations, chlorides of Sr, Ba Oxides of large quadrivalent cations (Zr, Hf, Ce, Th, U) |
Anti Flourite(face centered cubic) Example LiO2
In the related Anti-Fluorite structure Cation and Anion positions are reversed
 | Anions in CCP Cations in all Tetrahedral holes | Coordination number of anions is 8, cations is 4 | LiO2 , K2 , Na2O
Oxides /chalcogenides of alkali metals |
Zinc blend structure or Sphalerite (face centered cubic)
| Anions in CCP with cations in half Tetrahedral holes (only T+ {or T-} filled) | Coordination: 4:4 (tetrahedral) | ZnS
Formed from Polarizing Cations (Cu+, Ag+, Cd2+, Ga3+...) and Polarizable Anions (I-, S2-, P3-, ...); e.g. Cu(F,Cl,Br,I), AgI, Zn(S,Se,Te), Ga(P,As), Hg(S,Se,Te) |
Wurzite structure (Hexagonal P lattice)
| Anions in HCP , Cations in Alternate tetrahedral holes | Coordination: 4:4 (tetrahedral) | ZnS |
Corundum structure (HCP)
| Anions in HCP
Cations in 2/3 rd Octahedral holes | Cations - 6 Anions-4 | Al2O3 Fe2O3 Cr2O3 |
Perovskite structure
In the form ABO3
| A-Primitive unit cell B-Body centered cubic O-Face centred cubic | A-1 B-1 C-3 | CaTiO3 BaTiO3 |
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