Question

I have two questions.

Why can't dx2-y2 orbitals only make sigma bonds? If there is another dx2-y2 coming through z axis, can't they possibly make delta bonds since 4 overlappings seem possible?

Is there a reason why there is no dz2-y2 or dz2-x2 orbitals except experimental results?

Answer 1

The dx²2-y²2 orbitals can only form sigma bonds because their lobes are oriented towards the bonding axis. The dz²2-y²2 and dz²2-x²2 orbitals do not exist in the d orbital set. The shape and orientation of orbitals are determined by experimental results and theoretical calculations.

Step-by-step explanation:

The dx²-y² orbitals are part of the d orbital set and have a four-lobed shape. These orbitals can form sigma (σ) bonds because their lobes point directly towards the bonding axis. However, they cannot form pi (π) bonds, such as delta (δ) bonds, because their lobes are oriented perpendicular to the bonding axis.

As for the dz²-y² and dz²-x² orbitals, they do not exist in the d orbital set. The shape and orientation of atomic orbitals are determined by the wave function solutions to the Schrödinger equation, which are derived from experimental results and theoretical calculations.