Pariser—Parr Calculations and Electro-Optical Effects in Benzene

Abstract

Pariser—Parr calculations were done for the singlet states of benzene using singly and doubly excited configurations. Good agreement is obtained with the experimental locations of the ¹B_2u, ¹B_1u, and ¹E_1u states as well as the oscillator strength of the ¹A_1g→¹E_1u transition. The ¹E_2g state is calculated to be 0.5 eV above the ¹E_1u state and its photodissociation can be deduced from its bond orders. A possible assignment of the ¹A_1g→¹E_2g transition is discussed. On the basis of this simple model, electro‐optical effects are small, such as the Stark shift for the ¹E_1u and ¹B_1u states.