High-resolution infrared spectra and rovibrational analysis of the ν band of propylene oxide.

The high-resolution infrared spectrum of the fundamental band ν (ring breathing) of the chiral molecule propylene oxide (CHCHCHO) was recorded at room temperature and under jet-cooled conditions using a quantum cascade laser at 8 μm. The observed lines with quantum numbers ≤ 55 and ≤ 21 were assigned to strong - and -type bands, and some low transitions were classified as weak -type transitions. The lines were fitted using a Watsons A-reduced Hamiltonian in the I representation. From the rovibrational analysis the band origin as well as the rotational constants and four quartic centrifugal distortion constants were derived.