1. Quantum Mechanics and Bonding

2. QM to Explain Ionic Bonds
Transfer of electron from one orbital to another

3. QM to Explain Covalent Bonds
In grade 11 you noticed exceptions to the octet rule for molecular compounds
A more complex understanding than simple Lewis structures is required
Valence Bond Theory

4. Valence Bond Theory
A covalent bond forms when the atomic orbitals of 2 atoms overlap to share a common region in space
The region of overlap can contain a maximum of 2 electrons with opposite spins (Pauli exclusion principle)
The greater the overlap, the stronger the bond. Shape of overlap depends on the shape and orientation of orbitals involved
Orbital hybridization occurs when orbitals overlap and combine to form new orbitals