FORCE FIELD FOR OUT-OF-PLANE VIBRATIONS OF HALOGENATED AROMATIC MOLECULES

The general quadratic force field for the out of plane vibrations of the series C6H6, C6H5X, p-C6H4X2 and their deuterated analogues (X = F, Cl, Br) have been determined by perturbation procedures and by assuming transferability of the constants within a given X series. Agreement between the three sets of fields is excellent. Good agreement with the benzene fields proposed by Miller and Crawford, by Whiffen and by Scherer is also obtained. An alternative field for X = Br was found but is unacceptable by analogy with the X = F and Cl fields. © 1969.