The polarized Raman and infrared spectra of [1H4]- and [2H4]pyridazines were studied. Assignments of the normal vibrations made by previous workers were reexamined on the basis of polarization behavior of the Raman and infrared bands and also through the normal coordinate calculation, and reasonable assignments are presented.

Assignments of the out-of-plane normal vibrations of [1H5]- and [2H5]pyridines were reexamined based on the polarization behavior of the Raman bands and also through the normal coordinate calculation.