The Far-IR Spectra of UO2, α-U3O8, and γ-UO3 Using the Light Pipe Reflection Method

Abstract
The spectra of UO2, α-U3O8, and γ-UO3 in the 700–20 cm−1 range were examined with an FT-IR spectrometer with the use of a Cassegrainian-type light pipe cell. Generally, the light pipe reflection spectra obtained show more detail than the transmission measurements. Some weak peaks of lattice mode vibrations have been found. The coincidence of several spectral features in α-U3O8 and UO2 provides evidence that their structures are correlative. The spectra of γ-UO3 in this region are the first reported.