Mineralogy and crystal structure of bouazzerite from Bou Azzer, Anti-Atlas, Morocco: Bi-As-Fe nanoclusters containing Fe3+ in trigonal prismatic coordination

Brugger, Joël; Meisser, Nicolas; Krivovichev, Sergey V.; Armbruster, Thomas; Favreau, Georges

doi:10.2138/am.2007.2508

Cited by 16 publications

(2 citation statements)

References 25 publications

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“…Geminite1–4 Cu(AsO 3 OH)·H 2 O is a copper hydrogen‐arsenate with a triclinic structure usually found in the deposits of arsenic bearing CuPb ore deposits. Geminite is a member of a group of natural and synthetic compounds of the type A 1+ 2 (AsO 3 OH)· x H 2 O or A 2+ (AsO 3 OH)· x H 2 O, where A 1+ and A 2+ are monovalent and divalent cations, and x ≥ 0, inclusive such minerals as brassite—Mg(AsO 3 OH) · 4H 2 O, haidingerite—Ca(AsO 3 OH)·H 2 O, pushcharovskite—Cu(AsO 3 OH)·H 2 O, yvonite—Cu(AsO 3 OH)·H 2 O, krautite—Mn(AsO 3 OH)·H 2 O, fluckite—CaMn 2+ (AsO 3 OH) 2 · 2H 2 O, koritnigite—Zn(AsO 3 OH)·H 2 O and cobaltkoritnigite—(Co, Zn)(AsO 3 OH)·H 2 O 5.…”

Section: Introductionmentioning

confidence: 99%

Raman spectroscopy of hydrogen‐arsenate group (AsO₃OH) in solid‐state compounds: copper mineral phase geminite Cu(AsO₃OH)·H₂O from different geological environments

Sejkora¹,

Čejka²,

Frost³

et al. 2009

J Raman Spectroscopy

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The participation of hydrogen-arsenate group (AsO 3 OH) 2− in solid-state compounds may serve as a model example for explaining and clarifying the behaviour of As and other elements during weathering processes in natural environment. The mineral geminite, a hydrated hydrogen-arsenate mineral of ideal formula Cu(AsO 3 OH)·H 2 O, has been studied by Raman and infrared spectroscopies. Two samples of geminite of different origin were investigated and the spectra proved quite similar. In the Raman spectra of geminite, six bands are observed at 741, 812, 836, 851, 859 and 885 cm −1 (Salsigne, France), and 743, 813, 843, 853, 871 and 885 cm −1 (Jáchymov, Czech Republic). The band at 851/853 cm −1 is assigned to the ν 1 (AsO 3 OH) 2− symmetric stretching mode; the other bands are assigned to the ν 3 (AsO 3 OH) 2− split triply degenerate antisymmetric stretching mode. Raman bands at 309, 333, 345 and 364/310, 333 and 345 cm −1 are attributed to the ν 2 (AsO 3 OH) 2− bending mode, and a set of higher wavenumber bands (in the range 400-500 cm −1 ) is assigned to the ν 4 (AsO 3 OH) 2− split triply degenerate bending mode. A very complex set of overlapping bands is observed in both the Raman and infrared spectra. Raman bands are observed at 2289, 2433, 2737, 2855, 3235, 3377, 3449 and 3521/2288, 2438, 2814, 3152, 3314, 3448 and 3521 cm −1 . Two Raman bands at 2289 and 2433/2288 and 2438 cm −1 are ascribed to the strong hydrogen bonded water molecules. The Raman bands at 3235, 3305 and 3377/3152 and 3314 cm −1 may be assigned to the ν OH stretching vibrations of water molecules. Two bands at 3449 and 3521/3448 and 3521 cm −1 are assigned to the OH stretching vibrations of the (AsO 3 OH) 2− units. The lengths of the O-H· · ·O hydrogen bonds vary in the range 2.60-2.94 Å (Raman) and 2.61-3.07 Å (infrared). Two Raman and infrared bands in the region of the bending vibrations of the water molecules prove that structurally non-equivalent water molecules are present in the crystal structure of geminite.

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Section: Introductionmentioning

confidence: 99%

Raman spectroscopy of hydrogen‐arsenate group (AsO₃OH) in solid‐state compounds: copper mineral phase geminite Cu(AsO₃OH)·H₂O from different geological environments

Sejkora¹,

Čejka²,

Frost³

et al. 2009

J Raman Spectroscopy

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“…The unit is decorated by nine AsO 4 tetrahedra and three M 3+ cations with an asymmetric coordination mode induced by the stereoactivity of the s 2 electron pairs. Similarly to the cubic coordination of Ti 4+ and Fe 3+ cations in lehmannite and arsmirandite, the trigonal prismatic coordination of the central Fe 3+ cation in bouazzerite and whitecapsite is enforced by the geometrical requirements imposed by the overall cluster topology (Brugger et al, 2007). The Fe 7 skeleton of the cluster in the two minerals is similar to the Pt 7 core of the [Pt 7 O 6 (NO 2 ) 12 ] 8À cluster in the crystal structure of K 8 [Pt 7 O 6 (NO 2 ) 12 ] (Privalov et al, 1991), but the central Pt 4+ The [(UO 2 ) 24 (CO 3 ) 30 O 4 (OH) 12 (H 2 O) 8 ] 32À cluster in ewingite (a), its skeletal representation (b), the U core (c; the UÁ Á ÁU contacts shorter than 4 Å are shown as thick black lines; those between 4 and 6.2 Å as thin black lines; red and blue dots indicate centres of the U 3 trimers and midpoints of the shared UÁ Á ÁU edges of the U 4 dihedra, respectively), and the arrangements of the red and blue dots that correspond to the intersection of tetrahedron and octahedron, respectively (d).…”

Section: Miscellaneousmentioning

confidence: 99%

Polyoxometalate clusters in minerals: review and complexity analysis

Krivovichev¹

2020

Acta Crystallogr B Struct Sci Cryst Eng Mater

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Most research on polyoxometalates (POMs) has been devoted to synthetic compounds. However, recent mineralogical discoveries of POMs in mineral structures demonstrate their importance in geochemical systems. In total, 15 different types of POM nanoscale-size clusters in minerals are described herein, which occur in 42 different mineral species. The topological diversity of POM clusters in minerals is rather restricted compared to the multitude of moieties reported for synthetic compounds, but the lists of synthetic and natural POMs do not overlap completely. The metal–oxo clusters in the crystal structures of the vanarsite-group minerals ([As3+V4+ 2V5+ 10As5+ 6O51]7−), bouazzerite and whitecapsite ([M 3+ 3Fe7(AsO4)9O8–;n (OH) n ]), putnisite ([Cr3+ 8(OH)16(CO3)8]8−), and ewingite ([(UO2)24(CO3)30O4(OH)12(H2O)8]32−) contain metal–oxo clusters that have no close chemical or topological analogues in synthetic chemistry. The interesting feature of the POM cluster topologies in minerals is the presence of unusual coordination of metal atoms enforced by the topological restraints imposed upon the cluster geometry (the cubic coordination of Fe3+ and Ti4+ ions in arsmirandite and lehmannite, respectively, and the trigonal prismatic coordination of Fe3+ in bouazzerite and whitecapsite). Complexity analysis indicates that ewingite and morrisonite are the first and the second most structurally complex minerals known so far. The formation of nanoscale clusters can be viewed as one of the leading mechanisms of generating structural complexity in both minerals and synthetic inorganic crystalline compounds. The discovery of POM minerals is one of the specific landmarks of descriptive mineralogy and mineralogical crystallography of our time.

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Polyoxometalates and Other Metal-Oxo Clusters in Nature

Nyman¹

2016

Encyclopedia of Earth Sciences Series

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Mineralogy and crystal structure of bouazzerite from Bou Azzer, Anti-Atlas, Morocco: Bi-As-Fe nanoclusters containing Fe3+ in trigonal prismatic coordination

Cited by 16 publications

References 25 publications

Raman spectroscopy of hydrogen‐arsenate group (AsO₃OH) in solid‐state compounds: copper mineral phase geminite Cu(AsO₃OH)·H₂O from different geological environments

Raman spectroscopy of hydrogen‐arsenate group (AsO₃OH) in solid‐state compounds: copper mineral phase geminite Cu(AsO₃OH)·H₂O from different geological environments

Polyoxometalate clusters in minerals: review and complexity analysis

Polyoxometalates and Other Metal-Oxo Clusters in Nature

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Mineralogy and crystal structure of bouazzerite from Bou Azzer, Anti-Atlas, Morocco: Bi-As-Fe nanoclusters containing Fe3+ in trigonal prismatic coordination

Cited by 16 publications

References 25 publications

Raman spectroscopy of hydrogen‐arsenate group (AsO3OH) in solid‐state compounds: copper mineral phase geminite Cu(AsO3OH)·H2O from different geological environments

Raman spectroscopy of hydrogen‐arsenate group (AsO3OH) in solid‐state compounds: copper mineral phase geminite Cu(AsO3OH)·H2O from different geological environments

Polyoxometalate clusters in minerals: review and complexity analysis

Polyoxometalates and Other Metal-Oxo Clusters in Nature

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Raman spectroscopy of hydrogen‐arsenate group (AsO₃OH) in solid‐state compounds: copper mineral phase geminite Cu(AsO₃OH)·H₂O from different geological environments

Raman spectroscopy of hydrogen‐arsenate group (AsO₃OH) in solid‐state compounds: copper mineral phase geminite Cu(AsO₃OH)·H₂O from different geological environments