Studies on Hydrogen–Oxygen Systems in the Electrical Discharge. VI. Detection by Laser Raman Spectroscopy of O2 and O3 Trapped at 80 °K

Abstract

Further study by Raman spectroscopy of the condensed products from electrically dissociated water vapor and other related systems has revealed the presence, not only of ozone in appreciable amounts, but also of molecular oxygen in still greater amounts trapped at 80 °K. The concentration of ozone relative to the hydrogen oxides varied somewhat with experimental conditions, and also locally due to some segregation effect in the glassy condensate. The concentration of trapped oxygen showed still wider fluctuations depending particularly on surface effects in the discharge–flow system. On warming up under vacuum the intensity of the O2 and O3 bands began to decrease even before the crystallization temperature was reached (about 150 °K), thereby confirming that the gas evolution at that stage is mainly a desorption process. Therefore, the often quoted ratio of total evolved O2 to residual H2O2 could not be a reliable index of the formation of hydrogen polyoxides, H2O3 and H2O4, in these systems. A mechanism is proposed for the formation in situ of the trapped gases and in particular, for a source of oxygen atoms in dissociated water vapor.The fundamental vibrations of the ozone molecule, ν1 = 1106, ν2 = 703, and ν3 = 1036 cm−1, were confirmed by polarization and isotope shift measurements.