Inner and Outer Sphere ET Reactions

In a redox reaction, the oxidation states of the participating reactants are changed during the reaction, for example, 0 1 for H and 0 -2 for O in 

Actual transfer of electrons occurs in reaction (10.2), where the electrons in the initial reaction step are passed into an antibonding MO of the MnOj ion  

The two permanganate ions accept electrons from the alcohol molecule. During the reaction, the color changes from the beautiful violet of permanganate to the dull green of manganate, while the dubious smeU of schnapps is replaced by the wonderful odor of acetaldehyde. The reaction (10.2) is not a typical ET reaction, however, since bonds are broken and new molecules formed. 

In 1953, Henry Tanbe demonstrated the inner sphere mechanism, where two metal ions bind to the same ligand during the ET process. The total reaction is 

Co increases the occupancy of its 3d subshell by one unit and the valence state from -e3 to -e2, while Cr decreases the occupancy of its 3d shell by one unit and the valence state from -e2 to -e3. In other words, one electron is transferred from 

---