According to the crystal field theory, what causes the splitting of d-orbitals in octahedral transition metal complexes?

💡 Solution & Explanation

Crystal field theory explains d-orbital splitting in transition metal complexes as an electrostatic phenomenon where the approaching negative or dipolar ligands repel the d-electrons of the central metal ion differently depending on their spatial orientation. Orbitals pointing directly at the ligand axes experience greater repulsion and raise in energy, whereas those lying between axes experience lower repulsion. This energy difference corresponds to absorption bands in the visible spectrum, imparting characteristic colors to transition metal solutions.