Chem Connections

VSEPR - A Summary

Valence Shell Electron Pair Repulsion (VSEPR) theory allows the Chemist to predict the 3-dimensional shape of molecules from knowledge of their Lewis Dot structure. In VSEPR theory, the position of bound atoms (ligands) and electron pairs are described relative to a central atom. Once the ligands and lone pair electrons are positioned, the resulting geometrical shape presented by the atoms only (ignoring lone pairs) is used to describe the molecule.

Below is a table showing examples of the most common geometries encountered using the VSEPR theory. Clicking the cursor on the example molecules will allow you to view the 3-dimensional structure using RasMol v2.5-ucb. Only lone pair electrons on the central atom are shown.

<< Go Back

Copyright ©1995-2000 UC Regents
Last modified: 10/2/00 at 6:01 PM