Characterization of uranium tetrafluoride (UF₄) with Raman spectroscopy

Abstract

The Raman spectrum of uranium tetrafluoride (UF 4 ) is unambiguously characterized with multiple Raman excitation laser sources for the first time. Across different laser excitation wavelengths, UF 4 demonstrates 16 distinct Raman bands within the 50–400 cm −1 region. The observed Raman bands are representative of various F–F vibrational modes. UF 4 also shows intense fluorescent bands in the 325–750 nm spectral region. Comparison of the UF 4 spectrum with the ZrF 4 spectrum, its crystalline analog, demonstrates a similar Raman band structure consistent with group theory predictions for expected Raman bands. Additionally, a demonstration of combined scanning electron microscopy and in situ Raman spectroscopy microanalytical measurements of UF 4 particulates shows that despite the inherent weak intensity of Raman bands, identification and characterization are possible for micron‐sized particulates with modern instrumentation. The published well‐characterized UF 4 spectrum is extremely relevant to nuclear materials and nuclear safeguard applications. Published 2016. This article is a U.S. Government work and is in the public domain in the USA. Journal of Raman Spectroscopy published by John Wiley & Sons Ltd.