Raman spectroscopic study of the phosphate mineral churchite‐(Y) YPO₄·2H₂O

Abstract

Raman spectroscopy has been used to study the rare-earth mineral churchite-(Y) of formula (Y,REE)(PO 4 ) ·2H 2 O, where rareearth element (REE) is a rare-earth element. The mineral contains yttrium and, depending on the locality, a range of rare-earth metals. The Raman spectra of two churchite-(Y) mineral samples from Jáchymov and Medvědín in the Czech Republic were compared with the Raman spectra of churchite-(Y) downloaded from the RRUFF data base. The Raman spectra of churchite-(Y) are characterized by an intense sharp band at 975 cm −1 assigned to the ν 1 (PO 4 3− ) symmetric stretching mode. A lower intensity band observed at around 1065 cm −1 is attributed to the ν 3 (PO 4 3− ) antisymmetric stretching mode. The (PO 4 3− ) bending modes are observed at 497 cm −1 (ν 2 ) and 563 cm −1 (ν 4 ). Some small differences in the band positions between the four churchite-(Y) samples from four different localities were found. These differences may be ascribed to the different compositions of the churchite-(Y) minerals.

Raman spectroscopic study of the uranyl titanate mineral betafite (Ca,U)2(Ti,Nb)2O6(OH): effect of metamictization

“…Raman spectroscopy has proven very useful for the study of minerals (7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20). Indeed, Raman spectroscopy has proven most useful for the study of diagenetically related minerals as often occurs with minerals containing uranyl groups (7-9, 14, 21).…”

The recent weathering of uraninite from the Červená vein, Jáchymov (Czech Republic): a fingerprint of the primary mineralization geochemistry onto the alteration association

“…It is already known that Y and REE are more abundant in the vein cluster Rovnost, dominated by the Geister vein. From the outcrops and also underground workings located on this vein are known xenotime-(Y), agardite-(Y) and churchite-(Y) (Ondruš et al 1997(Ondruš et al , 2003aFrost et al 2010; unpublished data of the current authors) as well as the samples of uranyl-carbonate mineral kamotoite-(Y) (Ondruš et al 1997). Unfortunately, the latter cannot be localized within a particular vein.…”

“…The Ca . Recently, two exotic minerals were described rom the northern Caucasus: elbrusite-(Zr) and vorlanite (Galuskina et al 2010;Galuskin et al 2011). The former is an U-bearing garnet, where U (as well as Ca) is bounded into highly metamict domains of the crystals.…”

From Two-Dimensional Layers to Three-Dimensional Frameworks: Expanding the Structural Diversity of Uranyl Compounds by Cation–Cation Interactions

“…This deviation might be explained as a consequence of the different U−O terminal bond distances. 50,51 Owing to CCIs, the U−O bond distances are more abnormal in CsUW-2 (U−O terminal ranging from 1.80(1) Å to 1.82(1) Å for CsUW-1 whereas, from 1.76(2) Å to 1.99(2) Å for CsUW-2). The peaks between 750 and 800 cm −1 for both compounds could be assigned to the symmetric stretching (v 1 ) of UO 2 2+ .…”