MO diagrams: bond order, bond length, magnetism

The AOs of the two atoms on the sides, the MOs in the centre, joined by lines to the AOs they come from. Bonding MOs below the AOs, antibonding ones ($\sigma^*$, $\pi^*$) above, non-bonding ones ($n$) at the same energy as the parent AO. Filling: increasing energy, Pauli, then Hund in degenerate levels.