Question

For tetrahedral complexes, we have been drawing the e (dz^2 and dx^2-y^2 ) orbitals on the bottom and t2*(dxy, dyz, dxz) on top,

but when we are trying to find out about the Jahn-teller distortion, are we supposed to draw t2 orbitals on the bottom like we did for octahedral complexes?

Answer 1

Answer:

In tetrahedral complexes, the crystal field splitting is inverse of that in octahedral complexes i.e., t_{​​​​​​2g} set of orbitals lies above the "Barycentre" and e​​​​​_{​​​​​​g} set of orbitals lies below the Barycentre.

As far as Jahn Teller distortion is concerned, the original splitting remains the same as in tetrahedral complexes but the very "Jahn Teller effect" is weak and insignificant. This is because in tetrahedral complexes the direction of approach of the ligands does not coincide with the orientation of d-orbitals i.e., ligands approach the d orbitals sideways causing little electrostatic repulsions and the consequent "breaking" of degeneracy does not have much practical significance.