Table of Coordination Geometries
A table of the coordination geometries encountered is shown below with examples of their occurrence in complexes found as discrete units in compounds and coordination spheres around atoms in crystals (where there is no discrete complex).
| Coordination number | Geometry | Examples of discrete (finite) complex | Examples in crystals | |
|---|---|---|---|---|
| 2 | linear | Ag(CN)2− in KAg(CN)2 | Ag in silver cyanide, Au in AuI |
|
| 3 | trigonal planar | Cu(CN)32− in Na2Cu(CN)3.3H2O | O in TiO2 rutile structure | |
| 4 | tetrahedral | CoCl42− | Zn and S in zinc sulfide, Si in silicon dioxide | |
| 4 | square planar | AgF4− | CuO | |
| 5 | trigonal bipyramidal | SnCl5− | ||
| 5 | square pyramidal | InCl52− in (NEt4)2InCl5 | ||
| 6 | octahedral | Fe(H2O)62+ | Na and Cl in NaCl | |
| 6 | trigonal prismatic | Mo(SCHCHS)3 | As in NiAs, Mo in MoS2 | |
| 7 | pentagonal bipyramidal | ZrF73− in (NH4)3ZrF7 | Pa in PaCl5 | |
| 7 | face capped octahedral | La in A-La2O3 | ||
| 7 | trigonal prismatic, square face monocapped | TaF72− in K2TaF7 | ||
| 8 | cubic | Caesium chloride, calcium fluoride | ||
| 8 | square antiprismatic | TaF83− in Na3TaF8 | Thorium(IV) iodide | |
| 8 | dodecahedral (note: whilst this is the term generally used, the correct term is "bisdisphenoid" or "snub disphenoid" as this polyhedron is a deltahedron) |
Mo(CN)84− in K4.2H2O | Zr in K2ZrF6 | |
| 8 | hexagonal bipyramidal | N in Li3N | ||
| 8 | octahedral, trans-bicapped | Ni in nickel arsenide, NiAs; 6 As neighbours + 2 Ni capping | ||
| 8 | trigonal prismatic, triangular face bicapped | Ca in CaFe2O4 | ||
| 8 | trigonal prismatic, square face bicapped | PuBr3 | ||
| 9 | trigonal prismatic, square face tricapped | 2− in potassium nonahydridorhenate | SrCl2.6H2O, Th in RbTh3F13 | |
| 9 | monocapped square antiprismatic | La in LaTe2 | ||
| 10 | bicapped square antiprismatic | Th(C2O4)42− | ||
| 11 | Th in (NO3− is bidentate) | |||
| 12 | icosahedron | Th in Th(NO3)62− ion in Mg.8H2O | ||
| 12 | cuboctahedron | ZrIV(η3−(BH4)4) | atoms in fcc metals e.g. Ca | |
| 12 | anticuboctahedron (triangular orthobicupola) | atoms in hcp metals e.g. Sc | ||
| 14 | bicapped hexagonal antiprismatic | U(BH4)4 |
Read more about this topic: Coordination Geometry
Famous quotes containing the word table:
“When he was at the table with them, he took bread, blessed and broke it, and gave it to them. Then their eyes were opened, and they recognized him; and he vanished from their sight.”
—Bible: New Testament, Luke 24:30,31.
The Emmaus story.