chemistry Chemistry is the scientific study of the properties and behavior of matter. It is a physical science within the natural sciences that studies the chemical elements that make up matter and chemical compound, compounds made of atoms, molecules a ...

, the capped octahedral molecular geometry describes the shape of compounds where seven atoms or groups of atoms or ligands are arranged around a central atom defining the vertices of a gyroelongated triangular pyramid. This shape has C_3v

symmetry Symmetry () in everyday life refers to a sense of harmonious and beautiful proportion and balance. In mathematics, the term has a more precise definition and is usually used to refer to an object that is Invariant (mathematics), invariant und ...

and is one of the three common shapes for heptacoordinate transition metal complexes, along with the

pentagonal bipyramid The pentagonal bipyramid (or pentagonal dipyramid) is a polyhedron with ten triangular faces. It is constructed by attaching two pentagonal pyramids to each of their bases. If the triangular faces are equilateral, the pentagonal bipyramid is an ...

and the capped trigonal prism. Examples of the capped octahedral molecular geometry are the heptafluoromolybdate () and the heptafluorotungstate () ions. The " distorted octahedral geometry" exhibited by some AX₆E₁ molecules such as

xenon hexafluoride Xenon hexafluoride is a noble gas compound with the formula XeF6. It is one of the three binary fluorides of xenon that have been studied experimentally, the other two being XeF2 and XeF4. All of them are exergonic and stable at normal temperatur ...

(XeF₆) is a variant of this geometry, with the lone pair occupying the "cap" position.

References

Stereochemistry Molecular geometry {{molecular-geometry-stub