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Question
How does the magnitude of Δ0 decide the actual configuration of d orbitals in a coordination entity?
Solution
- If Δ0 < P, the fourth electron enters one of the eg orbitals giving the configuration \[\ce{t^3_{2g}e^1_g}\]. Ligands for which Δ0 < P are known as weak field ligands and form high spin complexes.
- If Δ0 > P, it becomes more energetically favourable for the fourth electron to occupy a t2g orbital with configuration \[\ce{t^4_{2g}e^0_g}\]. Ligands which produce this effect are known as strong field ligands and form low spin complexes.
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(iii) With strong field Ligands, Mn(II) complexes can be low spin.
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The correct statements are:
On the basis of crystal field theory, write the electronic configuration for the d5 ion with a weak ligand for which Δ0 < P.
On the basis of Crystal Field Theory, write the electronic configuration of d4 ion if Δ0 > P.
