What is the relationship between CFT and the color of metal complexes?

Here’s a explanation:

1. Crystal Field Theory (CFT) says that when ligands surround a metal ion, the metal’s d-orbitals split into different energy levels.
2. Light absorption: Electrons in the lower-energy d-orbitals can jump to higher-energy d-orbitals if they absorb light of the right energy.
3. Color: The metal complex shows the complementary color of the light it absorbs.
   • Example: If it absorbs red light, it looks green.
4. What affects the color:
   • Type of metal and its charge
   • Type of ligands (some ligands make bigger splitting)
   • Shape of the complex (octahedral, tetrahedral, etc.)

In short: CFT explains the splitting of d-orbitals → electrons jump when they absorb light → the complex shows color.