Capped octahedral molecular geometry

In chemistry, 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 C3v symmetry and is one of the three common shapes for heptacoordinate transition metal complexes, along with the pentagonal bipyramid and the capped trigonal prism.[1][2]

Capped octahedral molecular geometry
ExamplesMoF
7
Point groupC3v
Coordination number7

Examples of the capped octahedral molecular geometry are the heptafluoromolybdate (MoF
7
) and the heptafluorotungstate (WF
7
) ions.[3][4]

The "distorted octahedral geometry" exhibited by some AX6E1 molecules such as xenon hexafluoride (XeF6) is a variant of this geometry, with the lone pair occupying the "cap" position.

References

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  1. ^ Roald. Hoffmann; Barbara F. Beier; Earl L. Muetterties; Angelo R. Rossi (1977). "Seven-coordination. A molecular orbital exploration of structure, stereochemistry, and reaction dynamics". Inorganic Chemistry. 16 (3): 511–522. doi:10.1021/ic50169a002.
  2. ^ Wells A.F. (1984) Structural Inorganic Chemistry 5th edition Oxford Science Publications ISBN 0-19-855370-6
  3. ^ Kaupp, Martin (2001). ""Non-VSEPR" Structures and Bonding in d(0) Systems". Angew Chem Int Ed Engl. 40 (1): 3534–3565. doi:10.1002/1521-3773(20011001)40:19<3534::AID-ANIE3534>3.0.CO;2-#. PMID 11592184.
  4. ^ Zhenyang Lin; Ian Bytheway (1996). "Stereochemistry of Seven-Coordinate Main Group and d0 Transition Metal Molecules". Inorganic Chemistry. 35 (3): 594–603. doi:10.1021/ic950271o.