2.2.4
VSEPR Model
Valence Shell Electron Pair Repulsion Theory.
Principle
Electron domains repel each other and orient themselves as far apart as possible.
Repulsion Hierarchy
Lone Pair–Lone Pair > Lone Pair–Bonding Pair > Bonding Pair–Bonding Pair
Geometries (Up to 4 Domains)
Linear
180°
Trig. Planar
120°
Tetrahedral
109.5°
Pyramidal
<109.5°
Bent
≈104.5°
| Domains | Lone Pairs | Electron Geometry | Molecular Geometry | Angle |
|---|---|---|---|---|
| 2 | 0 | Linear | Linear | 180° |
| 3 | 0 | Trigonal Planar | Trigonal Planar | 120° |
| 3 | 1 | Trigonal Planar | Bent (V-shaped) | <120° |
| 4 | 0 | Tetrahedral | Tetrahedral | 109.5° |
| 4 | 1 | Tetrahedral | Trigonal Pyramidal | <109.5° |
| 4 | 2 | Tetrahedral | Bent (V-shaped) | ≈104.5° |