inorganic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

Agardite-(Y), Cu2+6Y(AsO4)3(OH)6·3H2O

aDepartment of Geosciences, University of Arizona, 1040 E. 4th Street, Tucson, Arizona 85721-0077, USA, and bLunar and Planetary Laboratory, University of Arizona, 1629 E. University Blvd., Tucson, AZ. 85721-0092, USA
*Correspondence e-mail: shaunnamm@email.arizona.edu

(Received 24 July 2013; accepted 21 August 2013; online 31 August 2013)

Agardite-(Y), with a refined formula of Cu2+5.70(Y0.69Ca0.31)[(As0.83P0.17)O4]3(OH)6·3H2O [ideally Cu2+6Y(AsO4)3(OH)6·3H2O, hexa­copper(II) yttrium tris­(arsenate) hexa­hydroxide trihydrate], belongs to the mixite mineral group which is characterized by the general formula Cu2+6A(TO4)3(OH)6·3H2O, where nine-coordinated cations in the A-site include rare earth elements along with Al, Ca, Pb, or Bi, and the T-site contains P or As. This study presents the first structure determination of agardite-(Y). It is based on the single-crystal X-ray diffraction of a natural sample from Jote West mine, Pampa Larga Mining District, Copiapo, Chile. The general structural feature of agardite-(Y) is characterized by infinite chains of edge-sharing CuO5 square pyramids (site symmetry 1) extending down the c axis, connected in the ab plane by edge-sharing YO9 polyhedra (site symmetry -6..) and corner-sharing AsO4 tetra­hedra (site symmetry m..). Hy­droxyl groups occupy each corner of the CuO5-square pyramids not shared by a neighboring As or Y atom. Each YO9 polyhedron is surrounded by three tubular channels. The walls of the channels, parallel to the c axis, are six-membered hexa­gonal rings comprised of CuO5 and AsO4 polyhedra in a 2:1 ratio, and contain free mol­ecules of lattice water.

Related literature

For background to the mixite mineral group, see: Dietrich et al. (1969[Dietrich, J. E., Orliac, M. & Permingeat, F. (1969). Bull. Soc. Fr. Minéral. Cristallogr. 92, 420-434.]); Hess (1983[Hess, H. (1983). N. Jahrb. Miner. Mh., 9, 385-392.]); Aruga & Nakai (1985[Aruga, A. & Nakai, I. (1985). Acta Cryst. C41, 161-163.]); Mereiter & Preisinger (1986[Mereiter, K. & Preisinger, A. (1986). Anz. Österr. Akad. Wiss. Math.-Naturwiss. Kl. 123, 79-81.]); Olmi et al. (1988[Olmi, F., Sabelli, C. & Brizzi, G. (1988). Miner. Rec. 19, 305-310.]); Miletich et al. (1997[Miletich, R., Zemann, J. & Nowak, M. (1997). Phys. Chem. Miner. 24, 411-422.]); Kunov et al. (2002[Kunov, A. Y., Nakov, R. A. & Stanchev, C. D. (2002). N. Jahrb. Miner. Mh., 2002, 107-116.]); Frost et al. (2005[Frost, R. L., Erickson, K. L., Weier, M., Mckinnon, A. R., Williams, P. A. & Leverett, P. (2005). Thermochim. Acta, 427, 167-170.]); Sejkora et al. (2005[Sejkora, J., Novotný, P., Novák, M., Šrein, V. & Berlepsch, P. (2005). Can. Mineral. 43, 1393-1400.]); Plášil et al. (2009[Plášil, J., Sejkora, J., Cejka, J., Škoda, R. & Goliáš, V. (2009). J. Geosci. 54, 15-56.]). For research on the sorption of toxic chemicals by minerals, see: Leone et al. (2013[Leone, V., Canzano, S., Iovino, P., Salvestrini, S. & Capasso, S. (2013). Chemosphere, 91, 415-420.]). For information on mineral nomenclature, see: Hatert & Burke (2008[Hatert, F. & Burke, E. A. J. (2008). Can. Mineral. 46, 717-728.]).

Experimental

Crystal data
  • Cu5.70(Y0.69Ca0.31)[(As0.83P0.17)O4]3(OH)6·3H2O

  • Mr = 985.85

  • Hexagonal, P 63 /m

  • a = 13.5059 (5) Å

  • c = 5.8903 (2) Å

  • V = 930.50 (6) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 13.13 mm−1

  • T = 293 K

  • 0.10 × 0.02 × 0.02 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2004[Bruker (2004). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.353, Tmax = 0.779

  • 20461 measured reflections

  • 786 independent reflections

  • 674 reflections with I > 2σ(I)

  • Rint = 0.048

Refinement
  • R[F2 > 2σ(F2)] = 0.032

  • wR(F2) = 0.086

  • S = 1.14

  • 786 reflections

  • 60 parameters

  • 1 restraint

  • H-atom parameters not refined

  • Δρmax = 2.34 e Å−3

  • Δρmin = −0.79 e Å−3

Data collection: APEX2 (Bruker, 2004[Bruker (2004). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2004[Bruker (2004). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: XtalDraw (Downs & Hall-Wallace, 2003[Downs, R. T. & Hall-Wallace, M. (2003). Am. Mineral. 88, 247-250.]); software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

Minerals of the mixite group crystallize in the mixite-structure type in space group P63/m and with Z = 2. Minerals of this and other groups, where the crystal structures exhibit channels (occupied by lattice water molecules), are of particular industrial and environmental interest due to their potential applications in the sorption of toxic chemicals (Leone et al., 2013) and as catalysts (Miletich et al., 1997; Frost et al., 2005). The mixite group can be characterized by the general formula Cu2+6A(TO4)3(OH)6.3H2O, where the nine-coordinated A site represents a rare earth element (REE), Al, Ca, Pb, or Bi, and the T site is P or As. There are currently ten members of this group: mixite [Cu2+6Bi(AsO4)3(OH)6.3H2O], zálesíite [Cu6Ca(AsO4)2(AsO3OH)(OH)6.3H2O], agardite-(Ce) [Cu2+6Ce(AsO4)3(OH)6.3H2O], agardite-(La) [Cu2+6La(AsO4)3(OH)6.3H2O], agardite-(Nd) [Cu2+6Nd(AsO4)3(OH)6.3H2O], agardite-(Y) [Cu2+6Y(AsO4)3(OH)6.3H2O], goudeyite [Cu6Al(AsO4)3(OH)6.3H2O], plumboagardite [Cu6(Pb,La,Nd,Ce,Ca)(AsO4)3(OH)6.3H2O], petersite-(Y) [Cu6Y(PO4)3(OH)6.3H2O], and calciopetersite [Cu6Ca(PO4)2(PO3OH)(OH)6.3H2O].

Due to its small crystal size and acicular habit, only the crystal structures of agardite-(Ce) (Hess, 1983), mixite (Mereiter & Preisinger, 1986; Miletich et al., 1997) and zálesíite (Aruga & Nakai, 1985) have been reported thus far. Notably, Aruga & Nakai (1985) studied a sample with composition [(Ca0.40REE0.42Fe0.09)Cu6.19[(AsO4)2.42(HAsO4)0.49](OH)6.38.3H2O] that they called a Ca-rich agardite. With the description of a new Ca-rich member of the mixite group, calciopetersite (Sejkora et al., 2005), the sample studied by Aruga and Nakai (1985) should be called zálesíite (Hatert & Burke, 2008).

Agardite-(Y) was first described from the oxidation zone of the Bou-Skour copper deposit in Jebel Sahro, Morocco (Dietrich et al., 1969). It has since been found in many other localities, including Germany, England, Spain, France, U.S. (Dietrich et al., 1969), Italy (Olmi et al., 1988), Czech Republic (Plášil et al., 2009) and Bulgaria (Kunov et al., 2002). In these studies, unit-cell parameters were presented, but no details of the crystal structure. Amid identification of minerals for the RRUFF project (http://rruff.info/R070649), we detected sprays of relatively large, well-crystalized, acicular agardite-(Y) from the Jote West mine, Pampa Larga Mining District, Copiapo, Chile (Fig. 1). Thereby, this study represents the first crystal structure determination of agardite-(Y), by means of single-crystal X-ray diffraction.

The structure of agardite-(Y) consists of infinite chains of edge-sharing CuO5 square-pyramids (site symmetry 1) extending down the c-axis, connected in the ab-plane by edge-sharing, YO9-polyhedra (site symmetry 6..) and corner-sharing AsO4-tetrahedra (site symmetry m..) (Fig. 2). Hydroxyl groups (OH4 & OH5) occupy each corner of the CuO5-polyhedra not shared by a neighboring As or Y atom. Based on bond valance calculations, OH4 (bond valance sum = 1.07 valence units (v.u.)) donates a hydrogen bond to O1 (bond valance sum = 1.93 v.u.), at the apex of the CuO5-polyhedron, while also accepting a hydrogen bond from OH5 (bond valance sum = 1.26 v.u.). Each YO9-polyhedron is surrounded by three tubular channels (Fig. 3). The walls of the channels, parallel to the c-axis, are 6-membered, hexagonal rings comprised of CuO5- and AsO4-polyhedra in a ratio of 2:1, respectively, and contain free molecules of lattice water. The water positions form a ring inside the channel, similar to the 2.7 Å radius ring reported by Hess (1983) in agardite-(Ce) and the five water sites reported by Miletich et al. (1997). In our model of agardite-(Y), we defined two distinct water sites, OW1 and OW2, although there are many statistically possible locations. OW1 is positioned as a 2.93 Å radius ring inside the channel and OW2 is situated at the center of the channel. This sample's Raman spectrum (Fig. 4) shows a broad H2O band, centered at 3400 cm-1, and protruding from it are two small bands signifying two OH modes.

Previous studies have utilized thermogravimetric analysis to examine the nature of both the lattice water and the Hydroxyl groups in synthetic mixite-group minerals (Miletich et al., 1997; Frost et al., 2005). In both studies, ~3 lattice (channel) H2O molecules were driven off when samples were heated to 373 K, and dehydroxylation was observed when temperatures reached 523 K. Mixite structural decomposition occurs upon the loss of the hydroxyl groups, which is made evident by the inability to rehydrate samples heated above the 523 K level (Miletich et al., 1997). Previously, the lattice water was thought to also contribute to the stability of the mixite-group crystal structure; however, Miletich et al. (1997) showed a very low value of activation energy for dehydration in mixite, indicating that the water molecules are not bonded to any cation. Our findings support the hypothesis that such water molecules are not involved in bonding; Cu—OW bond lengths are >3.5 Å and bond valance calculations show Cu (valence sum = 2.11 v.u.) and As (valence sum = 5.19 v.u.) to be fully bonded. Therefore, it appears that lattice water is not essential to the stability of the agardite-(Y) crystal structure.

Related literature top

For background to the mixite mineral group, see: Dietrich et al. (1969); Hess (1983); Aruga & Nakai (1985); Mereiter & Preisinger (1986); Olmi et al. (1988); Miletich et al. (1997); Kunov et al. (2002); Frost et al. (2005); Sejkora et al. (2005); Plášil et al. (2009). For research on the sorption of toxic chemicals by minerals, see: Leone et al. (2013). For information on mineral nomenclature, see: Hatert & Burke (2008).

Experimental top

The agardite-(Y) specimen used in this study was from the Jote West mine, Pampa Larga Mining District, Copiapo, Chile and is in the collection of the RRUFF project (deposition No. R070649; http://rruff.info). The chemical composition was determined with a CAMECA SX100 electron microprobe at the conditions of 25keV, 20nA, and a focused beam. An average of 16 analysis points yielded (wt. %): Al2O3 0.59, P2O5 3.09, CaO 3.72, MnO 0.10, CuO 43.18, As2O5 30.92, Y2O3 5.97, Gd2O3 0.18, Tb2O3 0.02, Dy2O3 0.25, Ho2O3 0.10, Er2O3 0.32, Yb2O3 0.22, H2O (by difference) 11.00. The empirical chemical formula is (Cu5.33Al0.12Ca0.03Mn0.01)Σ=5.49(Y0.52Er0.02Dy0.01Yb0.01Ho0.01Ca0.43)Σ=1.00[(AsO4)0.88(PO4)0.14]3(OH)6·2.99H2O.

Refinement top

Due to similar X-ray scattering power, all REE were treated as Y. Y and Ca were allowed to share the A-site and their abundances were refined under consideration of full occupancy. Additionally, As and P were allowed to share the T-site and their abundances were also constrained under consideration of full occupancy. The occupancy of the Cu site was refined freely, revealing a slight underoccupation of 0.950 (9). Various models were attempted in refining the lattice water positions, including split-site models. However, the refinement adopted here is the only one that converged. The exceptionally large isotropic displacement parameters for OW1 and OW2 are expected because these site represent essentially free molecules in a large channel. The total number of O atoms for the two water sites was constrained to 6. H atoms could not be assigned reliably and were excluded from refinement. The highest residual peak in the difference Fourier maps was located at (0, 0, 0.5), 0.00 Å from OW2, and the deepest hole at (0.4927, 0.8006, 0.3668), 0.91 Å from As.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XtalDraw (Downs & Hall-Wallace, 2003); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. Photograph of the agardite-(Y) specimen analyzed in this study, illustrating its acicular habit.
[Figure 2] Fig. 2. The crystal structure of agardite-(Y). Yellow square-pyramids, gray tetrahedra and blue polyhedra represent CuO5, AsO4 and YO9 units, respectively. Cyan spheres, with arbitrary radius, represent the O atoms of lattice water molecules.
[Figure 3] Fig. 3. The crystal structure of agardite-(Y) represented with displacement ellipsoids at the 99% probability level. Yellow, gray, blue and red ellipsoids represent Cu, As, Y and O, respectively. O atoms of lattice water molecules, shown as cyan spheres, are represented with an arbitrary radius.
[Figure 4] Fig. 4. Raman spectrum of agardite-(Y). The broad water vibration band is centered at 3400 cm-1, and the two small bands protruding from the water band signifying two OH modes.
Hexacopper(II) calcium/yttrium tris(arsenate/phosphate) hexahydroxide trihydrate top
Crystal data top
Cu5.70(Y0.69Ca0.31)[(As0.83P0.17)O4]3(OH)6·3H2ODx = 3.519 Mg m3
Mr = 985.85Mo Kα radiation, λ = 0.71073 Å
Hexagonal, P63/mCell parameters from 786 reflections
Hall symbol: -P 6cθ = 2.3–27.6°
a = 13.5059 (5) ŵ = 13.13 mm1
c = 5.8903 (2) ÅT = 293 K
V = 930.50 (6) Å3Acicular needle, green
Z = 20.10 × 0.02 × 0.02 mm
F(000) = 936
Data collection top
Bruker APEXII CCD
diffractometer
786 independent reflections
Radiation source: fine-focus sealed tube674 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.048
ϕ and ω scanθmax = 27.6°, θmin = 3.0°
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
h = 1717
Tmin = 0.353, Tmax = 0.779k = 1717
20461 measured reflectionsl = 67
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.032H-atom parameters not refined
wR(F2) = 0.086 w = 1/[σ2(Fo2) + (0.0413P)2 + 5.6747P]
where P = (Fo2 + 2Fc2)/3
S = 1.14(Δ/σ)max = 0.020
786 reflectionsΔρmax = 2.34 e Å3
60 parametersΔρmin = 0.79 e Å3
1 restraint
Crystal data top
Cu5.70(Y0.69Ca0.31)[(As0.83P0.17)O4]3(OH)6·3H2OZ = 2
Mr = 985.85Mo Kα radiation
Hexagonal, P63/mµ = 13.13 mm1
a = 13.5059 (5) ÅT = 293 K
c = 5.8903 (2) Å0.10 × 0.02 × 0.02 mm
V = 930.50 (6) Å3
Data collection top
Bruker APEXII CCD
diffractometer
786 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
674 reflections with I > 2σ(I)
Tmin = 0.353, Tmax = 0.779Rint = 0.048
20461 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0321 restraint
wR(F2) = 0.086H-atom parameters not refined
S = 1.14Δρmax = 2.34 e Å3
786 reflectionsΔρmin = 0.79 e Å3
60 parameters
Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
Y0.66670.33330.25000.0084 (5)0.69 (2)
Ca0.66670.33330.25000.0084 (5)0.31 (2)
Cu0.41303 (5)0.31598 (5)0.50234 (10)0.0113 (2)0.950 (9)
As0.49505 (6)0.15100 (6)0.75000.0087 (3)0.828 (15)
P0.49505 (6)0.15100 (6)0.75000.0087 (3)0.172 (15)
O10.5739 (3)0.1820 (3)0.5182 (6)0.0161 (9)
O20.3919 (5)0.4007 (4)0.25000.0180 (12)
O30.4124 (5)0.2123 (5)0.75000.0180 (12)
OH40.3688 (5)0.3768 (5)0.75000.0174 (12)
OH50.4421 (5)0.2456 (5)0.25000.0233 (14)
OW10.134 (3)0.170 (3)0.25000.221 (15)*0.7676 (7)
OW20.00000.00000.50001.4 (4)*0.697 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Y0.0102 (5)0.0102 (5)0.0048 (7)0.0051 (3)0.0000.000
Ca0.0102 (5)0.0102 (5)0.0048 (7)0.0051 (3)0.0000.000
Cu0.0183 (4)0.0153 (4)0.0042 (4)0.0113 (3)0.0006 (2)0.0003 (2)
As0.0116 (4)0.0086 (4)0.0055 (4)0.0048 (3)0.0000.000
P0.0116 (4)0.0086 (4)0.0055 (4)0.0048 (3)0.0000.000
O10.0184 (18)0.0214 (19)0.0109 (17)0.0118 (16)0.0039 (14)0.0024 (14)
O20.029 (3)0.025 (3)0.009 (2)0.020 (3)0.0000.000
O30.025 (3)0.020 (3)0.012 (3)0.013 (2)0.0000.000
OH40.027 (3)0.023 (3)0.009 (2)0.017 (2)0.0000.000
OH50.042 (4)0.026 (3)0.011 (3)0.023 (3)0.0000.000
Geometric parameters (Å, º) top
Y—O1i2.384 (3)Cu—OH51.908 (3)
Y—O1ii2.384 (3)Cu—OH41.911 (3)
Y—O1iii2.384 (3)Cu—O21.982 (3)
Y—O12.384 (3)Cu—O32.019 (4)
Y—O1iv2.384 (3)Cu—O1iv2.290 (4)
Y—O1v2.384 (3)As—O1vi1.652 (3)
Y—OH5ii2.647 (6)As—O11.652 (3)
Y—OH5iv2.647 (6)As—O31.690 (5)
Y—OH52.647 (6)As—O2vii1.692 (5)
O1i—Y—O1ii136.02 (6)O1v—Y—OH5iv67.84 (12)
O1i—Y—O1iii80.86 (13)OH5ii—Y—OH5iv120.000 (1)
O1ii—Y—O1iii83.01 (17)O1i—Y—OH567.84 (12)
O1i—Y—O183.01 (17)O1ii—Y—OH5138.49 (8)
O1ii—Y—O180.86 (13)O1iii—Y—OH5138.49 (8)
O1iii—Y—O1136.02 (6)O1—Y—OH567.84 (12)
O1i—Y—O1iv136.02 (6)O1iv—Y—OH568.19 (12)
O1ii—Y—O1iv80.86 (13)O1v—Y—OH568.19 (12)
O1iii—Y—O1iv136.02 (6)OH5ii—Y—OH5120.0
O1—Y—O1iv80.86 (13)OH5iv—Y—OH5120.0
O1i—Y—O1v80.86 (13)OH5—Cu—OH4174.6 (3)
O1ii—Y—O1v136.02 (6)OH5—Cu—O280.14 (17)
O1iii—Y—O1v80.86 (13)OH4—Cu—O299.09 (17)
O1—Y—O1v136.02 (6)OH5—Cu—O398.49 (17)
O1iv—Y—O1v83.01 (17)OH4—Cu—O381.53 (16)
O1i—Y—OH5ii68.19 (12)O2—Cu—O3172.1 (2)
O1ii—Y—OH5ii67.84 (12)OH5—Cu—O1iv84.2 (2)
O1iii—Y—OH5ii67.84 (12)OH4—Cu—O1iv101.26 (19)
O1—Y—OH5ii68.19 (12)O2—Cu—O1iv96.13 (18)
O1iv—Y—OH5ii138.49 (8)O3—Cu—O1iv91.46 (18)
O1v—Y—OH5ii138.49 (8)O1vi—As—O1111.5 (3)
O1i—Y—OH5iv138.49 (8)O1vi—As—O3112.08 (15)
O1ii—Y—OH5iv68.19 (12)O1—As—O3112.08 (15)
O1iii—Y—OH5iv68.19 (12)O1vi—As—O2vii108.17 (16)
O1—Y—OH5iv138.49 (8)O1—As—O2vii108.17 (16)
O1iv—Y—OH5iv67.84 (12)O3—As—O2vii104.4 (3)
Symmetry codes: (i) x, y, z+1/2; (ii) y+1, xy, z; (iii) y+1, xy, z+1/2; (iv) x+y+1, x+1, z; (v) x+y+1, x+1, z+1/2; (vi) x, y, z+3/2; (vii) y, x+y, z+1.

Experimental details

Crystal data
Chemical formulaCu5.70(Y0.69Ca0.31)[(As0.83P0.17)O4]3(OH)6·3H2O
Mr985.85
Crystal system, space groupHexagonal, P63/m
Temperature (K)293
a, c (Å)13.5059 (5), 5.8903 (2)
V3)930.50 (6)
Z2
Radiation typeMo Kα
µ (mm1)13.13
Crystal size (mm)0.10 × 0.02 × 0.02
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2004)
Tmin, Tmax0.353, 0.779
No. of measured, independent and
observed [I > 2σ(I)] reflections
20461, 786, 674
Rint0.048
(sin θ/λ)max1)0.651
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.032, 0.086, 1.14
No. of reflections786
No. of parameters60
No. of restraints1
H-atom treatmentH-atom parameters not refined
Δρmax, Δρmin (e Å3)2.34, 0.79

Computer programs: APEX2 (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XtalDraw (Downs & Hall-Wallace, 2003), publCIF (Westrip, 2010).

 

Acknowledgements

The authors gratefully acknowledge Robert A. Jenkins for providing the agardite-(Y) specimen to the RRUFF Project. Funding support of this study is from the Arizona Science Foundation, ChevronTexaco, and NASA NNX11AP82A, Mars Science Laboratory Investigations. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Aeronautics and Space Administration.

References

First citationAruga, A. & Nakai, I. (1985). Acta Cryst. C41, 161–163.  CrossRef CAS Web of Science IUCr Journals
First citationBruker (2004). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.
First citationDietrich, J. E., Orliac, M. & Permingeat, F. (1969). Bull. Soc. Fr. Minéral. Cristallogr. 92, 420–434.  CAS
First citationDowns, R. T. & Hall-Wallace, M. (2003). Am. Mineral. 88, 247–250.  CAS
First citationFrost, R. L., Erickson, K. L., Weier, M., Mckinnon, A. R., Williams, P. A. & Leverett, P. (2005). Thermochim. Acta, 427, 167–170.  Web of Science CrossRef CAS
First citationHatert, F. & Burke, E. A. J. (2008). Can. Mineral. 46, 717–728.  Web of Science CrossRef CAS
First citationHess, H. (1983). N. Jahrb. Miner. Mh., 9, 385–392.
First citationKunov, A. Y., Nakov, R. A. & Stanchev, C. D. (2002). N. Jahrb. Miner. Mh., 2002, 107–116.  Web of Science CrossRef
First citationLeone, V., Canzano, S., Iovino, P., Salvestrini, S. & Capasso, S. (2013). Chemosphere, 91, 415–420.  Web of Science CrossRef CAS PubMed
First citationMereiter, K. & Preisinger, A. (1986). Anz. Österr. Akad. Wiss. Math.-Naturwiss. Kl. 123, 79–81.
First citationMiletich, R., Zemann, J. & Nowak, M. (1997). Phys. Chem. Miner. 24, 411–422.  CrossRef CAS Web of Science
First citationOlmi, F., Sabelli, C. & Brizzi, G. (1988). Miner. Rec. 19, 305–310.  CAS
First citationPlášil, J., Sejkora, J., Cejka, J., Škoda, R. & Goliáš, V. (2009). J. Geosci. 54, 15–56.
First citationSejkora, J., Novotný, P., Novák, M., Šrein, V. & Berlepsch, P. (2005). Can. Mineral. 43, 1393–1400.  Web of Science CrossRef CAS
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals
First citationWestrip, S. P. (2010). J. Appl. Cryst. 43, 920–925.  Web of Science CrossRef CAS IUCr Journals

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