An ab Initio Study of Some Phenyl- and (Halophenyl)alkali Compounds.

Ab initio calculations are presented for alkali metal derivatives of fluoro- and chlorobenzenes for comparison with previously determined experimental substitutent effects. Calculated substituent effects for one alkali metal are linearly related to those of another. (Difluorophenyl)lithiums show additivity of substituent effects calculated from (monofluorophenyl)lithiums but dichloro derivatives do not, an effect attributed to the higher polarizability of chlorine. meta- and para-fluoro substituents show excellent agreement with experiment. ortho-fluoro and chlorine substituents do not. These differences are rationalized.