Reinterpretation of the Electron Spin Resonance Spectrum of the o-Xylene Negative Ion

The electron spin resonance spectrum of the o-xylene negative ion has been re-examined in view of a discrepancy between one of the previously reported splitting constants and the predictions of molecular orbital theory. This splitting constant has been found to be 1.81 G instead of ∼0.2 G. The new values of the hyperfine splittings reported here are in excellent agreement with the predictions of both molecular orbital and valence bond theory. A technique is described by which molecules such as o-xylene can be reduced.