Final answer:
For two orbitals to bond, they need to have the same symmetry. However, having the same Mulliken label is not a strict requirement for orbital overlap and bonding.
Explanation:
When considering the bonding of orbitals, the key factor is their symmetry. Orbitals with the same symmetry can overlap effectively, leading to the formation of a bond. The overlap between atomic orbitals contributes to the creation of molecular orbitals in a molecule.
Symmetry labels are used to describe the symmetry of an orbital. For example, the s, p, and d orbitals have specific symmetries, and within each type, there are different orientations with varying symmetries. While having the same symmetry is crucial for effective orbital overlap, it's not necessary for orbitals to have the same Mulliken label.
Mulliken labels describe the symmetry of an orbital based on its behavior under certain symmetry operations. While these labels are useful for understanding the characteristics of orbitals, the focus is on their symmetry rather than their specific Mulliken label when determining their ability to form bonds.
In summary, orbitals with the same symmetry can form effective overlaps, facilitating bonding. Mulliken labels help characterize the symmetry of orbitals, but having the same label is not a strict prerequisite for successful orbital overlap and bond formation.