CH-Bindungsmomente und IR-Intensität von Benzol-Derivaten—II. CH- und CD-Valenzschwingungen deuterierter Benzol-Monoderivate

The absorption intensities of the CH and CD stretching vibrations of some deuterated benzene monoderivatives have been measured in CCl₄ solution. The compounds are of the type 4-D-phenyl-X and 2,4,6-D₃-phenyl-X. The observed intensities can be interpreted as sum of contributions I_o, I_m, and I_p, of the participating CH or CD oscillators. By using also the data for the undeuterated compounds phenyl-X these bond contributions can be evaluated separately. They show a decrease with the Taft substituent parameter σ_I, that is greatest in ortho and smallest in para position. The isotope intensity sum rule is verified for the CH and CD stretching vibrations in all the cases considered.