Raman spectroscopic study of the uranyl carbonate mineral čejkaite and its comparison with synthetic trigonal Na₄[UO₂(CO₃)₃]

Abstract

Raman and infrared spectroscopies were used to characterise two samples of triclinicčejkaite Na 4 [UO 2 (CO 3 ) 3 ] and its synthetic trigonal analogue. The ν 3 (UO 2 ) 2+ mode is not Raman active, whereas both the ν 3 and ν 1 (UO 2 ) 2+ modes are infrared active. U-O bond lengths in uranyls were calculated from the spectra obtained and compared with bond lengths derived from crystal structure analyses. From the higher number of bands related to the uranyl and carbonate vibrations, the presence of symmetrically distinct (UO 2 ) 2+ and (CO 3 ) 2− units in both structures is proposed.

Recent advances in linear and nonlinear Raman spectroscopy. Part V

“…Vibrational analyses of the following minerals have been carried out by Frost and coworkers using Raman scattering and other related techniques: the arsenite mineral finnemanite Pb 5 (As 3+ O 3 ) 3 Cl; the multi‐anion mineral dixenite, CuMn 2+ 14 Fe 3+( AsO 3 ) 5 (SiO 4 ) 2 (AsO 4 )(OH) 6 ; vajdakite, [(Mo 6+ O 2 ) 2 (H 2 O) 2 As 2 3+ O 5 ]‐H 2 O; triclinic cejkaite Na 4 [UO 2 (CO 3 ) 3 ] and its synthetic trigonal analog; the arsenite minerals leiteite ZnAs 2 O 4 , reinerite Zn 3 (AsO 3 ) 2 and cafarsite Ca 5 (Ti,Fe,Mn) 7 (AsO 3 ) 12 ‐4H 2 O; the antimonate mineral bahianite Al 5 Sb 5+ 3 O 14 (OH) 2 , a semi‐precious gemstone; the antimonate mineral bottinoite Ni[Sb 2 (OH) 12 ]‐6H 2 O and in comparison with brandholzite Mg[Sb 5+ 2 (OH) 12 ]‐6H 2 O; haidingerite Ca(AsO 3 OH)‐H 2 O and brassite Mg(AsO 3 OH)‐4H 2 O; the kaolinite‐like phyllosilicate minerals bismutoferrite BiFe 3+ 2 Si 2 O 8 (OH) and chapmanite SbFe 3+ 2 Si 2 O 8 (OH); the hydrogen‐arsenate mineral pharmacolite Ca(AsO 3 OH)‐2H 2 O with implications for aquifer and sediment remediation; the mineral gerstleyite Na 2 (Sb,As) 8 S 13 ‐2H 2 O and in comparison with some heavy‐metal sulfides; synthetic reevesite and cobalt substituted reevesite (Ni,Co) 6 Fe 2 (OH) 16 (CO 3 )‐4H 2 O; the mineral euchroite, a mineral involved in a complex set of equilibria between the copper hydroxy arsenates: euchroite Cu 2 (AsO 4 )(OH)‐3H 2 O‚ olivenite Cu 2 (AsO 4 )(OH)‚ strashimirite Cu 8 (AsO 4 ) 4 (OH) 4 ‐5H 2 O and arhbarite Cu 2 Mg(AsO 4 )(OH) 3 ; the mixite mineral BiCu 6 (AsO 4 ) 3 (OH) 6 ‐3H 2 O from the Czech Republic; the gallium‐based hydrotalcites of formula Mg 6 Ga 2 (CO 3 )(OH) 16 ‐4H 2 O; the indium‐based hydrotalcites of formula Mg6In 2 (CO 3 )(OH) 16 ‐4H 2 O; the hydroxy‐arsenate‐sulfate mineral chalcophyllite Cu 18 Al 2 (AsO 4 ) 4 (SO 4 ) 3 (OH) 24 ‐36H 2 O; the phosphate mineral churchite‐(Y) YPO 4 ‐2H2O; the synthesis of sodium hexatitanate from sodium trititanate was characterized by Raman spectroscopy, XRD and high‐resolution TEM; a Raman spectroscopic study on the allocation of ammonium‐adsorbing sites on H2Ti3O7 nanofibre and its structural derivation during calcination; and hydrogen‐arsenate group (AsO 3 OH) in solid‐state compounds: copper mineral phase geminite Cu(AsO 3 OH)‐H2O from different geological environments . Gomez et al .…”

Structure and Dynamics of the Uranyl Tricarbonate Complex in Aqueous Solution: Insights from Quantum Mechanical Charge Field Molecular Dynamics

“…There exist a number of different uranyl carbonates in aqueous solution which have been reported in the literature so far. Among them, besides the mononuclear UO 2 (CO 3 ), − [UO 2 (CO 3 ) 2 ] 2– ,,,− and the polynuclear [(UO 2 ) 3 (CO 3 ) 6 ] 6– , ,,, the tricarbonate [UO 2 (CO 3 ) 3 ] 4– ,,,,,,− is the most extensively studied because of its prevailing existence at environmental conditions in aqueous solution . Thus, uranyl tricarbonate is probably the dominant species in liquid bodies and therefore may be the key structure concerning uranium remediation from contaminated areas. − There is still a lot of experimental and theoretical work focused to further characterize the uranyl tricarbonate system in aqueous solution.…”

A Raman spectroscopic study of the ‘cave’ mineral ardealite Ca2(HPO4)(SO4)·4H2O

“…Raman spectroscopy has proved very useful for the study of minerals 12–25. Indeed Raman spectroscopy has proved most useful for the study of diagentically related minerals as often occurs with minerals containing sulfate and phosphate groups.…”