VSEPR theory electron and molecular geometries

Linear electron geometry

2 electron groups ie 2 bonded groups

sp hybridization

only one molecular geometry

Linear molecular geometry

Straight line = 180 degree bond angle

AX₂ no lone pair

Trigonal planar electron geometry

3 electron groups.

2 molecular geometries

sp² hybridisation

Trigonal planar molecular geometry

3 bonded atoms and NO lone pairs

120 degree bond angle. 3 atoms attached to central atom.

AX₃

Bent molecular geometry

3 electron groups: 2 bonded and 1 lone pair

120 degree angle

AX₂ with a lone pair

Tetrahedral electron geometry

4 electron groups

3 molecular geometries

109.5 bond angle

sp³ hybridisation

Tetrahedral molecular geometry

AX₄ : 4 bonded pairs and 0 lone pairs

e.g methane ie CH₄

Trigonal pyramidal molecular geometry

AX₄ : 3 bonded pairs and 1 lone pair

e.g NH₃ (bond angle 107/109.5 degrees)

Bent molecular geometry (for tetrahedral)

AX₄ : 2 bonded pairs and 2 lone pairs e.g water

109.5 (or 104.5 degrees with water)

Trigonal Bypyramidal electron structure

5 electron groups

4 molecular geometries

sp³d hybridisation

120 degree bond angle (in plane) and 90 degree bond angle above and below.

Trigonal Bipyramidal molecular geometry

AX₅ : 5 bonded pairs and 0 lone pairs

one bond on each side and then an extra on the side e.g PCl₅

Seesaw molecular geometry

AX₅ : 4 bonded pairs and 1 lone pair

e.g SF₄

T-shaped molecular geometry

AX₅ : 3 bonded pairs and 2 lone pairs

eg ClF₃

Linear (Trigonal Bypyramidal) molecular geometry

AX₅ : 2 bonded pairs and 3 lone pairs

180 degree bond angle

Octahedral electron geometry

90 degree bond angle

sp³d²

5 molecular geometries

6 electron groups

Octahedral molecular geometry

AX₆ : 6 bonded pairs and 0 lone pairs e.g SF₆

90 degree bond angle

Square pyrimidal molecular geometry

AX₆ : 5 bonded pairs and 1 lone pair

90 degree

Square planar molecular geometry

AX₆ : 4 bonded pairs and 2 lone pairs

T shaped molecular geometry (octahedral)

AX₆ : 3 bonded pairs and 3 lone pairs

Linear molecular geometry (octahedral)

AX₆ : 2 bonded pairs and 4 lone pairs

180 degrees