The electrons around the atoms in a molecule repel each other. They move to be as far apart as possible while still maintaining the bonding within the molecule. The procedure for using the model is as follows:
2) Count the number of electron groups around the central atom. A group of electrons is a bond, a nonbonding electron pair, or occasionally an unpaired nonbonding electron. Each triple or double bond counts as only one group for the purposes of this model.
3) Based on this number of groups around the central atom the
molecule falls into one of six basic
categories. Within each category there are a number of different
names for the shapes depending upon the number of atoms and nonbonding
groups around the central atom.
(click links below to see examples)
A = central atom
X = atom attached to central atom
E = nonbonding electron group on central atom
(this refers to the atom arrangement, ignoring the lone pairs)
Last Table Update: November 18, 2016