J. Org. Chem., Vol. 40, No. 24, 1975 3583
Reactivities of Benzenoid Hydrocarbons (13) J. Almlof, A. Kvick, and J. 0. Thomas, J. Chem. Phys., 59, 3901 (1973). (14) Use, instead, of the Slater-Kirkwood-Heilmann-Margenau equation [H. Margenau, Rev. Mod. Phys., 11, 1 (1939)], with the effective number of oscillating electrons per electron pair being taken as 2 throughout (and with the values of 01 and R unchanged), yields somewhat higher values of EL than does eq 1. The spacings among the substituents look seriously distorted, and understandablyZd,eso, but the sequence of substituents is stili F < CI < Br < H N _ i