Low Frequency Raman Spectra of α-16O2, α-18O2, and α-N2

Abstract

The low frequency Raman spectra of the 16O2 and 18O2 isotopes of oxygen have been compared in the α phase of the solid. The frequency of the line at 27 cm−1 is the same in both isotopes and this confirms its interpretation as due to spin wave or magnon excitation. The libron frequencies are lower in the 18O2 than in the 16O2 spectrum. The integrated relative intensity of the libron lines is smaller in the 18O2 spectrum.The observed α-N2 spectrum confirms that reported by Anderson et al. The frequencies of the lines decrease and their half-widths increase as the temperature is raised to the α–β transition.