The infrared spectrum of C2N2 in the region of the bending fundamental ν5

Abstract The high resolution infrared spectrum of C 2 N 2 in the region 200–270 cm −1 has been studied with a Fourier transform spectrometer. In addition to ν 5 , the “hot” bands 2 ν 5 0 ← ν 5 1 , 2 ν 5 2 ← ν 5 1 and 3 ν 5 3 ← 2 ν 5 2 have been analysed. Polynomial fits have been applied to obtain the vibrational term values and the rotational constants for the levels involved.