Brief introduction to d-orbital splitting, Russell-Saunders coupling, and application to UV-Vis spectroscopy using Tanabe-Sugano diagrams
A student should be able to:
1. Draw a d-orbital splitting digram for an octahedral complex.
2. Determine the L-S coupled ground state term for the metal cation.
3. Read a Tanabe-Sugano diagram to predict or understand a UV-Vis spectrum.
The Five Slides have web links as resources to expand the discussion presented on these slides. The slides should be used as an introduction, then problems should be attempted to implement the knowledge.
In-class and homework problems involving
(1) the identification (in a complex) of the charge and d-electron count of the central transition metal cation,
(2) determination of the ground state L-S coupled term,
(3) choosing the correct Tanabe-Sugano diagram for the d-electron count,
(4) predicting whether the d-electrons will be in a high-spin or low-spin configuration, baed on metal identity, charge, and ligand identities, and
(5) prediction of explanation of a UV-Vis spectrum using this information.
I have had mixed success with students. The shortcut to finding the GS term works well. Students have trouble deciding between high spin and low spin for a particular complex, especially with ammonia as a ligand.