Interelectronic repulsion energy complexes

The almost linear curve of the expected enthalpy changes is shown by blue dashed lines in the figure for hydration reactions of and ions. The differences between this curve and the double-humped experimental values are approximately equal to the LFSE values in Table 10.7 for high-spin complexes, with corrections for (1) spin-orbit coupling (0 to 16 kJ/mol), (2) a relaxation effect caused by contraction of the metal-ligand distance (0 to 24 kJ/mol), and (3) an interelectronic repulsion energy that depends on the exchange interactions between electrons with the same spins (0 to -19 kJ/mol for 0 to -156 kJ/ mol for In addition, small corrections must be made for cases in which the com-... 

One more consideration is necessary to understand the trends in these enthalpies. The interelectron repulsion energies for electrons in metal valence atomic orbitals are different (higher in magnitude) than for these electrons in the coordination complex orbitals. 

Table 13 Racah Interelectronic Repulsion Energies for Free Metal Cations, Weak- /Strong-Field Crossover Energies, d-Electron Configurations and LFSEs for Pseudo-Octahedral d" Complexes"...

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