Ligand held splitting

Within an octahedral E term, two parameters are required to describe the splitting of the electronic states due to a low symmetry ligand held,... 

An orbital correlation diagram for the splitting of the valence s, p and d orbitals of a transition metal in an octahedral ligand held is shown in Fig. 13.9 which is discussed in Section 13.4 which describes the bonding in TM hexacarbonyls. A schematic representation of all orbital terms which give a non zero contribution to the term is presented there in Fig. 13.10. 

The crystal field splitting in a tetrahedral field is intrinsically smaller than diai in an octahedral held because there are only two-thirds as many ligands and they have a less direct effect on the d orbitals. The point-charge model predicts that for the same metal ion, ligands, and metal-ligand distances. As a result, orbhal splitting... 

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