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Question
Why are different colours observed in octahedral and tetrahedral complexes for the same metal and same ligands?
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Solution
Lower wavelength is absorbed in octahedral complex than tetrahedral complex for the same metal and ligand. In tetrahedral coordination entity, formation of the d-orbital splitting is inverted and is smaller as compared to the octahedral field splitting. For the same metal-ligand complexes, it can be shown that
`Δ_t = (4/9)Δ_0`.
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