CK-12-Chemistry Intermediate

http://www.ck12.org Chapter 9. Covalent Bonding

The hybridization then occurs with a singlesorbital, threeporbitals, and a singledorbital. The set of five hybrid
orbitals are calledsp^3 dhybrids.

The overlap of the five hybridsp^3 dorbitals with the 3porbital of each chlorine atom results in the five covalent
bonds of PCl 5. Other molecular geometries derived from trigonal bipyramidal electron domain geometry (seesaw,
T-shaped, linear) also display the same hybridization.

Sulfur hexafluoride (SF 6 ) has an octahedral electron domain and molecular geometry. In this case, a 3sand a 3p
electron are each promoted to two empty 3dorbitals.

The hybridization now occurs with onesorbital, threeporbitals, and twodorbitals. The resulting set of six
equivalent orbitals are calledsp^3 d^2 hybrids.

The overlap of the six hybridsp^3 d^2 orbitals with the 2porbital of each fluorine atom results in the six covalent bonds
of SF 6. Other molecular geometries derived from an octahedral electron domain geometry (square pyramidal, square
planar) also exhibit this type of hybridization. The figure below (Figure9.42) shows the shape and orientation of
thesp^3 dandsp^3 d^2 hybrid orbital sets.

The process of hybridization can be summarized by the following steps:

1. Draw the Lewis electron-dot structure of the molecule.


2. Use VSEPR theory to predict both the electron domain geometry and the molecular geometry of the molecule.


3. Match the electron domain geometry to the appropriate hybridization of the central atom.

Summarized below (Table9.7) are all of the possibilities along with examples of each.

TABLE9.7: Summary of Hybrid Orbitals

Electron Domain

Geometry

Hybridization of the

Central Atom

Number of Hybrid

Orbitals

Possible Molecular

Geometries

Examples

Linear sp 2 linear BeH 2 , CO 2

Trigonal Planar sp^23 trigonal planar, bent BF 3 , CO 32 −, O 3