Electron Self-Exchanges of Organic Molecules

Electron-transfer reactions occur frequently between organic molecules and their radical cations or anions. A good example is the reaction between naphthalene and its radical anion 

One electron is transferred from a n orbital. The bond extensions occur on the carbon skeleton and do not significantly involve the CH bonds. The reactive bonds are therefore considered to be the CC bonds of the aromatic ring. Assuming that the carbon-carbon 

Stretching modes behave as normal modes, the effective force constant for naphthalene is given by 

Vibrational data are available from normal mode analysis of vibrational spectra, in particular from the symmetric stretching modes that employ valence force fields. For naphthalene, we obtain= 3.81 X10 kJ mol Using the same averaging manner, we can estimate the average bond length 

For the neutral naphthalene molecule, the average bond order of the carbon-carbon bonds is 

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