Valence Shell Electron Pair Repulsion — molecular geometry and bond angles.
VSEPR Theory:
Electron pairs arrange to minimize repulsion
Order: LP-LP > LP-BP > BP-BP
Bond Angles (ideal):
Linear: 180°
Trigonal Planar: 120°
Tetrahedral: 109.5°
Trigonal Bipyramidal: 90°, 120°, 180°
Octahedral: 90°, 180°
Hybridization:
2 domains → sp
3 domains → sp²
4 domains → sp³
5 domains → sp³d
6 domains → sp³d²
Molecular Polarity:
Polar: dipoles don't cancel (asymmetric)
Non-polar: dipoles cancel (symmetric)
LP affects shape and polarity