# Molecular Modeling

## Qualitative MO theory: Molecular orbitals for any system

The oxygen molecule is an example of a diatomic homonuclear molecule, the atomic orbitals are mixed to the molecular orbitals.

The orbital interaction diagram is shown below:

The s atomic orbitals are mixed to form bonding (σ) and antibonding (σ *) σ molecular orbitals. If one takes the x-axis as the bond axis, then the $px$-Orbitals also mixed to σ-molecular orbitals. the$py$ and $pz$-Atomorbitals become π-molecular orbitals when mixed.