Strong field configuration Alternate

The approach we have adopted for the d configuration began from the so-called strong-field limit. This is to be contrasted to the weak-field scheme that we describe in Section 3.7. In the strong-field approach, we consider the crystal-field splitting of the d orbitals first, and then recognize the effects of interelectron repulsion. The opposite order is adopted in the weak-field scheme. Before studying this alternative approach, however, we must review a little of the theory of free-ion spectroscopy... 

Table 13.1 Crystal field stabilization energies for weak field and intermediate field octahedral complexes. Where alternative configurations are given, the fractional values are the weak-field limit and the integer values are the strong-field limit (between them they give the intermediate field range)...

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