We have mentioned hybridization of the central atom before, but we really haven’t explained it much. Quantum Mechanics allows us to treat atomic orbitals as mathematical functions. Just as mathematical functions can be added or subtracted from one another, atomic orbitals can be “added or subtracted” from another. We refer to this phenomenon as “mixing.” The atomic orbitals on an atom can mix together to form hybrid orbitals.
9.5 Hybrid Orbitals