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Updated: May 1, 2026
High Pressure Single Crystal Diffraction at PX^2
Published on: January 16, 2017
A vibrational spectroscopic study of the phosphate mineral churchite (REE)(PO(4))⋅2H(2)O
Ray L Frost1, Andrés López1, Ricardo Scholz2
1School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4001, Australia.
Abstract:
Vibrational spectroscopy has been used to study the rare earth mineral churchite of formula (REE)(PO4)⋅2H2O. The mineral contains a range of rare earth metals including yttrium depending on the locality. The Raman spectra of churchite-(REE) are characterized by an intense sharp band at 984cm(-1) assigned to the ν1(PO4(3-)) symmetric stretching mode. A lower intensity band observed at around 1067cm(-1) is attributed to the ν3(PO4(3-)) antisymmetric stretching mode. The (PO4(3-)) bending modes are observed at 497cm(-1) (ν2) and 565cm(-1)(ν4). Raman bands at 649 and 681cm(-1) are assigned to water librational modes. Vibrational spectroscopy enables aspects of the structure of churchite to be ascertained.
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