Crystal field theory || CFT for octahedral complexes

Crystal Field theory

The important point of CFT:

  1. This theory considered the metal-ligand bond is purely ionic
  2. The electrostatic interaction between metal ion and ligands
  3. The ligand is anion metal atom is a cation
  4. If the ligand is a neutral molecule the negative ends of the dipole is attractive
    towards the metal atom
  5. It treats the ligand is a point of negative charge
  6. The arrangement of ligand around the central metal ion in such a way that repulsion should be minimum

Lets For example :

When ligand approaches metal ion (D-Orbitals), The ligand orbitals approach to D-orbitals of metal. Therefore there will be possible forces

A. Force of attraction

It will decrease the force if there will be more force of attraction. it means
there is low energy.

B. Force of repulsion
It will increase the force if there will be more force of attraction. it means there is high energy.

There are 5 D-orbitals in metal ion

Shape and Orientation of 5 D-orbitals in metal ion

In below image you can see, there are 5 types of D-orbitals

dz2, dxy, dxz, dyz , and dx2-y2

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