Effect of Pressure on the Spectra of Crystalline UF4and UF3

摘要

The effect of pressure has been measured on the crystalline spectra of UF4and UF3. The UF3, which has a structure analogous to PrF3and NdF3, behaved much like those compounds, showing a 15 to 40 increase in intensity for different peaks in 50 000 atm. In UF4certain of the peaks increased in intensity while others decreased. The U4+ion is almost at a center of symmetry in this crystal. It is indicated that the intensity behavior is reasonable if a significant fraction of the intensity is obtained due to lattice vibrations. Both red and blue shifts are observed on different peaks.