Characterisation of the O-O peroxide bond by vibrational spectroscopy

Only very few studies have been reported on organic peroxides, mainly because of their unstable and often explosive nature. Literature usually reports (P.A. Budinger, J.R. Mooney, J.G. Graselli and P.S. Fay, A.T. Guttmann, Anal. Chem., 53 (1981) 884) that the O-O stretching vibration is weak by IR and leads to an intense band between 700 and 950 cm(-1) by Raman spectroscopy. We have investigated by both these spectroscopic techniques some inorganic peroxides and 23 organic peroxides. Despite the fact that the O-O stretch occurs in a region where carbon skeletal modes may interfere, we were able to determine a narrower range of frequencies for this vibration: 845-875 cm(-1). This study has also demonstrated the influence of the peroxide group on the other functions of the molecule. We have noticed particularly some 40 cm(-1) shifts on the frequencies of a carbonyl vibration in the a position from the peroxide bond.