Spectrochemical Series
What is Spectrochemical Series?
The spectrochemical series is an empirically determined ranking of ligands in order of their ability to split the d-orbital energy levels of a transition metal ion (crystal field splitting, Δ). Strong-field ligands (such as CN⁻, CO, and NO₂⁻) produce large Δ values and tend to form low-spin complexes, while weak-field ligands (such as I⁻, Br⁻, and H₂O) produce small Δ values and tend to form high-spin complexes. The series is: I⁻ < Br⁻ < Cl⁻ < F⁻ < OH⁻ < H₂O < NH₃ < en < CN⁻ < CO.
Key Facts
Frequently Asked Questions
The spectrochemical series is an empirically determined ranking of ligands in order of their ability to split the d-orbital energy levels of a transition metal ion (crystal field splitting, Δ). Strong-field ligands (such as CN⁻, CO, and NO₂⁻) produce large Δ values and tend to form low-spin complexes, while weak-field ligands (such as I⁻, Br⁻, and H₂O) produce small Δ values and tend to form high-spin complexes. The series is: I⁻ < Br⁻ < Cl⁻ < F⁻ < OH⁻ < H₂O < NH₃ < en < CN⁻ < CO.