SHORT HYBRIDE handout

Simplified Hybridization and Molecular Geometry Method

Note - this method does not always yield the correct answer but will probably cover 90% of the problems you will encounter. This works especially well if the transition metals are not included.

1) Draw the Lewis structure of the molecule.

2) Count the number of electrons used in the Lewis structure.

3) Consider only the sigma bonding structure. That is, if there is a double bond, subtract 1 pair of electrons and if there is a triple bond, subtract 2 pair.

4) Use the following table to get the electron geometry and the molecular geometry. The molecular geometry is the same as the electron geometry when there is no lone pair of electrons.

Sigma Bonds	Lone pair	Count	Hybrid	Electron Geometry	Molecular Geometry
2	0	2	sp	Linear	Linear
3	0	3	sp²	Triangle	Triangle
2	1	3	sp²	Triangle	Bent 120^o
4	0	4	sp³	Tetrahedral	Tetrahedral
3	1	4	sp³	Tetrahedral	Trigonal pyramid
2	2	4	sp³	Tetrahedral	Bent 108^o
5	0	5	sp³d	Trigonal Bipyramid	Trigonal Bipyramid
4	1	5	sp³d	Trigonal Bipyramid	See-Saw
3	2	5	sp³d	Trigonal Bipyramid	T shaped
2	3	5	sp³d	Trigonal Bipyramid	Linear
6	0	6	sp³d²	Octahedron	Octahedron
5	1	6	sp³d²	Octahedron	Square Pyramid
4	2	6	sp³d²	Octahedron	Square Planar
3	3	6	sp³d²	Octahedron	T shaped
2	4	6	sp³d²	Octahedron	Linear