摘要：

The two ππ transitions observed in parabenzoquinone at 35 kK and 40 kK are given the labels 1 A- 1 K and 1 A- 1 J, respectively, arguing from the Platt free electron classification scheme. Formulas for the changes of intensity and shifts in transition frequency as a function of type, number, and position of substitution are derived, using the method which Petruska applied successfully to benzene. If "ortho effect" correction terms are introduced into the formulas whenever two substituents are adjacent to each other, the formulas for the intensity of the transition at 35 kK and for the frequency shifts of both transitions hold to within ±10% for methyl, methoxy, and hydroxy substitution. A proportionality is found between parameters computed for these formulas and the corresponding parameters found by Petruska for benzene.

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