Substituted benzenes infrared bending vibrations

Fig. 8.5. The out-of-plane sextant ring bend vibration in mono, ortho, meta, and para-substituted benzenes. The 1,3,5 ring carbons and the 2,4,6 ring carbons move oppositely out of the plane (+ and —). In mono, meta, and 1,3,5 trisubstituted benzenes, the vibration is IR active at 710-665 cm . When the substituents are identical in ortho and para isomers, this band is infrared inactive.

Topical Infrared C-H Out-of-Plane Bending Vibrations for Substituted Benzenes (cm )... 

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