Spectra of the xenon fluorides XeF2 and XeF4 in the far uv region

Abstract

The absorption of gaseous and solid XeF₂ and XeF₄ has been measured in the region of 50–160 eV. It was possible to reproduce the absorption line shapes observed between 61 and 73 eV by semiempirical calculations based on the one center‐one electron model. According to these results, the observed lines could be assigned to transitions from 4d and 4p Xe subshells into ``5p'', 6s, 6p, and 7p levels. The spin orbit splitting of the molecular 4d level has been found to be almost equal to the free atom case. For the first time, a ligand field splitting of core levels is observed. In addition to this, spin orbit and ligand field splittings are measured to occur in the upper levels. The $\text{4d→``5p''}$ transition in XeF₄ suggests a dynamic Jahn‐Teller effect. The gross structure of the spectra in both phases is practically identical for both XeF₂ and XeF₄. The absorption lines of the Rydberg transitions are strongly broadened in the spectra of the solidified gases.