Ligand exchange Watch
1. The oxidation state of the metal, which you pointed out.
2. The nature of the ligand. Different ligands have different effects on the d-orbital splitting. A ligand might cause a greater degree of splitting of d-orbitals. This means the electron absorbs more light energy, and therefore a higher wavelength of light, to be excited into the higher orbital.
3. The coordination number. An octahedral formation has a greater orbital splitting than a tetrahedral formation.
So while the oxidation state of the metal stays the same and the d-orbitals available stay the same, the separation of these orbitals can change by these ligands.
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