What are some examples of molecular orbitals?
The simplest molecular orbitals are the σ and σ orbitals formed by the overlap of atomic s* orbitals.
We also have σ(2p) and σ*(2p) orbitals formed by the end-on overlap of 2p orbitals.
In alkanes such as ethane we can also have σ orbitals formed by the overlap of atomic s and sp³ atomic orbitals in C-H bonds. The C-C bonds form by the overlap of sp³ atomic orbitals.
Molecular π orbitals form by the sideways overlap of atomic p orbitals.
Then we can have extended π orbitals. The four atomic orbitals on the C atoms in buta-1,3-diene overlap to form the four π orbitals.
These are only a few of the many molecular orbitals that are possible.