Ba[Co3(VO4)2(OH)2] with a regularKagome lattice

Tamara Ðordevica* and Ljiljana Karanovicb

aInstitut fur Mineralogie und Kristallographie, Universitat Wien-Geozentrum,

Althanstrasse 14, A-1090 Vienna, Austria, and bLaboratory of Crystallography,

Faculty of Mining and Geology, University of Belgrade, Ðusina 7, 11000 Belgrade,

Serbia

Correspondence e-mail: tamara.djordevic@univie.ac.at

Received 12 December 2012

Accepted 19 January 2013

Online 26 January 2013

The new layered title compound, barium di-�-hydroxido-di-

�-vanadato-tricobaltate(II), was prepared under low-temper-

ature hydrothermal conditions. Its crystal structure comprises

Co2+ and O2� ions in the Kagome geometry. The octahedral

Co3O6(OH)2 Kagome layers, made up of edge-shared CoO4-

(OH)2 octahedra with Co on a site of 2/m symmetry, alternate

along the c axis with barium vanadate heteropolyhedral layers,

in which Ba is on a site of 3m symmetry and V is on a site of 3m

symmetry. All three O atoms and the H atom also occupy

special positions: two O atoms and the H atom are on sites

with 3m symmetry and one O atom is on a site with m

symmetry. Ba[Co3(VO4)2(OH)2] represents the first com-

pound from the four-component BaO–CoO–V2O5–H2O

system and its structure is topologically related to the minerals

vesignieite, Ba[Cu3(VO4)2(OH)2], and bayldonite, Pb[Cu3-

(AsO4)2(OH)2].

Comment

There are many reports of divalent metal vanadates synthe-

sized by high-temperature solid-state reactions (Chen et al.,

2004; Azdouz et al., 2010; Huang et al., 2012, and references

therein). Hydrothermal methods have also proved to be

effective for the synthesis of new vanadium compounds

(Ðordevic & Karanovic, 2010; Ðordevic et al., 2008, and

references therein). Controlling the products of hydrothermal

syntheses is often difficult because of their high sensitivity to

specific reaction conditions. However, hydrothermal syntheses

often result in well developed single crystals. An ongoing

study concerning the low-temperature hydrothermal synth-

esis, crystallography and properties of arsenate and vana-

date(V) compounds in the system M1O–M2O–X2O5–H2O

(M1 = Sr, Cd, Ba, Bi, Hg; M2 = Mg, Mn, Fe, Co, Ni, Cu, Zn; X =

As, V) has yielded a large number of new M12+–(H), M22+–

(H) and M1–M2–(H) arsenates and vanadates (Ðordevic,

2011; Ðordevic & Karanovic, 2008, 2010; Weil et al., 2009;

Ðordevic et al., 2008, 2010; Stojanovic et al., 2012, and refer-

ences therein) that have been characterized structurally and,

in part, by spectroscopic techniques. These compounds often

form anionic frameworks built from MO6 octahedra and XO4

tetrahedra, with An+ cations as counter-ions.

We report here the hydrothermal synthesis and crystal

structure of barium di-�-hydroxido-di-�-vanadato-tricobal-

tate(II), Ba[Co3(VO4)2(OH)2]. In contrast with the topologi-

cally identical structures of vesignieite, Ba[Cu3(VO4)2-

(OH)2] (Ma et al., 1991), and bayldonite, Pb[Cu3(AsO4)2-

(OH)2] (Ghose & Wan, 1979), which are monoclinic, Ba[Co3-

(VO4)2(OH)2] crystallizes in the rhombohedral space group

R3m. Accordingly, it forms a structurally perfect Kagome

compound. It is well known that crystal structures containing

layers with a Kagome lattice arrangement display interesting

physical properties connected with geometrically frustrated

magnetism (Valldor et al., 2009; Caignaert et al., 2009; Olariu et

al., 2008). Unfortunately, however, the quality and size of the

Ba[Co3(VO4)2(OH)2] single crystals obtained in this work

have not yet permitted further measurements of the physical

properties.

In all three already mentioned M1[M23(XO4)2(OH)2]

compounds (M1 = Ba2+, Pb2+; M2 = Co2+, Cu2+; X = V, As), a

layered crystal structure has been found. There are two types

of regularly alternating layers parallel to the (001) planes, viz.

octahedral M23O6(OH)2 Kagome layers separated by layers of

XO4 tetrahedra and M1 cations in similar coordination

environments (Fig. 1). In Ba[Co3(VO4)2(OH)2], the Co3O6-

(OH)2 layers of the CoO4(OH)2 octahedra, with Co2+ and

O22� ions in a two-dimensional Kagome network, alternate

along the c axis with barium vanadate anticuboctahedral–

tetrahedral layers (Figs. 1 and 2). In the octahedral layers, six-

membered octahedral rings are formed by edge-sharing of

adjacent tetragonally shortened CoO4(OH)2 octahedra

(Table 1 and Fig. 2). The Co2+ cation is surrounded by four

equatorial oxide ligands [four symmetry equivalents of atom

inorganic compounds

114 # 2013 International Union of Crystallography doi:10.1107/S0108270113001972 Acta Cryst. (2013). C69, 114–118

Acta Crystallographica Section C

Crystal StructureCommunications

ISSN 0108-2701

Figure 1A perspective view of the crystal structure of Ba[Co3(VO4)2(OH)2].Large grey spheres represent Ba1 and small spheres represent H1 atoms.The VO4 tetrahedra are black and the CoO4(OH)2 octahedra are hatchedgrey.

O2, with Co1—O2 = 2.161 (2) A] and two axial hydroxide

ligands [two symmetry equivalents of group O3—H1, with

Co1—O3 = 1.9449 (19) A; Table 1 and Figs. 2 and 3]. The

oxide ligands bridge between Co2+ centres to form an ideal

Kagome network composed of Co1O22 triangles (Fig. 4a). The

distance between two Co2+ cations is 2.9605 (4) A.

In the comparable monoclinic Ba[Cu3(VO4)2(OH)2] struc-

ture (Ma et al., 1991), there are two crystallographically

distinct positions for Cu and four for O, while in Pb[Cu3-

(AsO4)2(OH)2] (Ghose & Wan, 1979), there are three posi-

tions for Cu and five for O, due to the lower symmetry.

Although in Ba[Cu3(VO4)2(OH)2] there are two Jahn–Teller-

distorted Cu2+ cations in the Kagome plane, the distortion of

the CuO2 triangle from a regular geometry is negligible

[2.9624 (5) A for Cu1—Cu2 and 2.9555 (5) A for Cu2—Cu2].

In Pb[Cu3(AsO4)2(OH)2], with three Cu sites, the distortion of

the CuO2 triangle is somewhat larger, with the distances

between two Cu2+ cations being 2.9460 (5) A for Cu1—Cu2,

2.9334 (4) A for Cu1—Cu3 and 2.9334 (5) A for Cu2—Cu3

(Fig. 4b).

In Ba[Co3(VO4)2(OH)2], the BaO12 polyhedron with Ba2+

at Wyckoff position 3b (0, 0, 12) (site symmetry 3m) is an

anticuboctahedron with six shorter [2.824 (3) A] and six

longer [3.4186 (5) A] distances (Table 1). The average Ba—O

distance of 3.121 A is slightly longer than the average Ba—O

inorganic compounds

Acta Cryst. (2013). C69, 114–118 Ðordevic and Karanovic � Ba[Co3(VO4)2(OH)2] 115

Figure 2A projection of a single Kagome layer perpendicular to the c axis, formedby edge-sharing of adjacent CoO4(OH)2 octahedra. H atoms are shown assmall spheres.

Figure 3The coordination environment of the Ba, Co and V sites, showing theatom-numbering scheme. Displacement ellipsoids are drawn at the 70%probability level. The shorter Ba—O, Co—O and V—O bonds are shownas solid bonds and the longer Ba—O bonds are shown as open bonds. TheH� � �O contacts are shown as dashed lines. [Symmetry codes: see Table 1;additionally: (xiv) y � 1

3, x + y + 13, �z + 4

3; (xv) �x + 23, �y + 1

3, �z + 43.]

Figure 4A Kagome network consisting of triangles and hexagons. The views show(a) a regular network, as in Ba[Co3(VO4)2(OH)2] (black spheresrepresent Cu1 atoms and grey spheres represent O2 atoms), and (b) adistorted newwork, as in Pb[Cu3(AsO4)2(OH)2] (differently lined blackspheres represent Cu1, Cu2 and Cu3 atoms, and grey spheres representO1, O2 and O3 atoms).

distance of 3.093 A in Ba[Cu3(VO4)2(OH)2]. Around the

smaller Pb2+ cation in Pb[Cu3(AsO4)2(OH)2], only eight O

atoms are in the first coordination sphere, making a square

antiprism with an average Pb—O distance of 2.721 A. The

next four Pb—O bonds, which are longer than 3.5 A, contri-

bute collectively to the bond-valence sum (Brese & O’Keeffe,

1991) by �10%. The differences in coordination for the M1

atoms are a consequence of the cation sizes and small shifts of

the O atoms, caused by different orientations of the XO4

tetrahedra (Fig. 4).

The mutually isolated slightly-distorted VO4 tetrahedra

have one short [1.661 (6) A] and three longer [1.745 (3) A]

bonds (V—Oave = 1.724 A). The short V—O bond involves

atom O1, which is further bonded to three adjacent Ba2+

cations at longer distances and acts as the acceptor of a strong

hydrogen bond (Table 2). The longer V—O bonds involve

atom O2, which is further bonded to one Ba2+ cation at a

shorter distance, and to two Co2+ cations. A similar distortion

of the VO4 tetrahedra was found in Ba[Cu3(VO4)2(OH)2],

where all V—O bonds are, in general, slightly shorter and

range from 1.631 (6) to 1.7393 (3) A (V—Oave = 1.712 A). In

the AsO4 tetrahedra of Pb[Cu3(AsO4)2(OH)2], there are two

shorter and two longer bonds, which vary from 1.6646 (2) to

1.7229 (2) A, and the average As—O distance (1.695 A) is, as

expected, shorter than V—Oave.

Atom H1 is localized near O3, which is further bonded to

the three neighbouring Co2+ cations at shorter distances.

Bond-valence sums for all atoms, calculated using the para-

meters of Brese & O’Keeffe (1991), give 1.68 v.u. (valence

units) for Ba1, 2.14 v.u. for Co1 and 4.98 v.u. for V1. These

values suggest that the Ba2+ cation is underbonded in its 12-

coordinate site, while Co is slightly overbonded. Considering

the contribution of the non-H atoms only, the bond-valence

sums for the O atoms are 1.61 (O1), 1.97 (O2), and 1.52 v.u.

(O3). Taking into account that atom O3 is the single donor of a

strong hydrogen bond towards atom O1, the bond valences

are well balanced (Table 2).

The present results show that Ba[Co3(VO4)2(OH)2] is not

structurally identical to Ba[Cu3(VO4)2(OH)2] and Pb[Cu3-

(AsO4)2(OH)2]. The main difference is the higher rhombo-

hedral symmetry. Thus, the Kagome network in Ba[Co3-

(VO4)2(OH)2] is regular and closely similar but not identical

to those in Ba[Cu3(VO4)2(OH)2] and Pb[Cu3(AsO4)2(OH)2].

Since Ba2+ is larger than Pb2+, Ba2+ is bonded to 12 O atoms,

while Pb2+ is bonded to only eight. In order to compare the

unit-cell dimensions, the monoclinic unit cells were trans-

formed to the corresponding rhombohedral cells (Table 3).

The resulting cells are almost identical for Ba[Co3(VO4)2-

(OH)2] and Ba[Cu3(VO4)2(OH)2], and, as expected, slightly

smaller for Pb[Cu3(AsO4)2(OH)2].

In the literature, there are several compounds with Co

atoms in the sites of the Kagome lattice, with Ba atoms

incorporated in the adjacent layers. Isostructural rhombo-

hedral mixed-valence Ba2Co4ClO7 and Ba2Co4BrO7 (Kauff-

mann et al., 2007) have hole-filled Kagome layers that consist

of edge-sharing octahedra. Co3+ cations are positioned in the

octahedral sites of the Kagome lattice, whereas Co2+ cations

are situated at the centres of the hexagons formed by the

Kagome lattice, i.e. they occupy the Kagome holes. Layers

built up from corner-sharing CoO6 octahedra, CoO4 tetra-

hedra and Ba2+ cations sandwich the Kagome layers to form

[Ba2Co8O14]2� blocks. Similar blocks are found in Ba2Co9O14

and Ba3Co10O17 (Sun et al., 2006; Ehora et al., 2007). It is

interesting to note the jarosite-type compounds, with the

general formula AM3(SO4)2(OH)6 (A = Na, K, Rb, Tl; M =

Fe3+, Cr3+, V3+), which adopt the same space group as

Ba[Co3(VO4)2(OH)2] also belong to the class of Kagome

compounds. One member of this group is NaV3(SO4)2(OD)6

jarosite, with V3+ cations in the positions of the Kagome lattice

(Grohol et al., 2003). In contrast with the linking role of the

VO4 tetrahedra in Ba[Co3(VO4)2(OH)2], where V is in the +5

oxidation state, V can create the Kagome lattice in jarosite as a

+3 cation.

The Ba[Co3(VO4)2(OH)2] structure is also related to the

rhombohedral (space group P31c) and orthorhombic (space

group Pbn21) mixed-valence compound YbBaCo4O7 (Huq et

al., 2006). YbBaCo4O7 is one member of the class of

compounds with the general formula RBaCo4O7, where R is Y,

Tb, Dy, Ho, Er, Tm, Yb or Lu (Khalyavin et al., 2009, and

references therein), better known as ‘114’ oxides. These

structures are characterized by Kagome layers of CoO4

tetrahedra. There are two symmetry-independent CoO4

tetrahedra, one forming the Kagome layers and the other

linking these layers along the c axis. These tetrahedra appear

in a 1:3 ratio, which is in accordance with the nominal stoi-

chiometry YbBaCo3+Co2+3O7. Similar structures are found for

rhombohedral (space group P31c) YBaAlCo3O7 (Valldor et

al., 2008) and orthorhombic (space group Pbn21) CaBaCo4O7

(Caignaert et al., 2009).

Although all the above-mentioned compounds have

Kagome layers, it is interesting to note the diverse role of Co,

i.e. it can be Co2+, Co3+ or mixed valence, and in an octahedral

or tetrahedral coordination. In addition, the composition and

geometry of the layers which sandwich the Kagome layers and

incorporate Ba2+ cations can be very different. Ba[Co3-

(VO4)2(OH)2] is a specific example of an ideal Kagome

compound, having a structure which consists of 1:1 ordered

stacking of novel barium vanadate anticuboctahedral–tetra-

hedral layers and Kagome layers of tetragonally shortened

CoO4(OH)2 octahedra.

Experimental

Single crystals of Ba[Co3(VO4)2(OH)2] were obtained as reaction

products from a mixture of Ba(OH)2�H2O (Mallinckrodt 3772,

>97%), Co powder (Merck 1221) and V2O5 (Fluka Chemika 94710,

98%). The mixture was transferred to a Teflon vessel and filled to

approximately 75% of the inner volume with distilled water. The pH

of the mixture was 12. The Teflon vessel was enclosed in a stainless

steel autoclave, which was then heated under a three-step heating

regime: the autoclave was heated from 293 to 423 K (4 h), held at

423 K for 120 h and finally cooled to room temperature within 96 h.

At the end of the reaction, the pH of the solution was 6. The reaction

products were filtered off and washed thoroughly with distilled water.

inorganic compounds

116 Ðordevic and Karanovic � Ba[Co3(VO4)2(OH)2] Acta Cryst. (2013). C69, 114–118

Ba[Co3(VO4)2(OH)2] crystallized as transparent pale-pink needle-

like crystals up to 0.2 mm in length (yield ca 35%), together with an

uninvestigated powder consisting of dark- and light-brown crusts and

undissolved V2O5 (yield ca 65%).

Crystal data

Ba[Co3(VO4)2(OH)2]Mr = 578.03Rhombohedral, R3ma = 5.9210 (8) Ac = 21.016 (4) AV = 638.07 (18) A3

Z = 3Mo K� radiation� = 12.42 mm�1

T = 298 K0.07 � 0.06 � 0.04 mm

Data collection

Nonius KappaCCD area-detectordiffractometer

Absorption correction: multi-scan(Otwinowski et al., 2003)Tmin = 0.477, Tmax = 0.637

1909 measured reflections222 independent reflections215 reflections with I > 2�(I)Rint = 0.023

Refinement

R[F 2 > 2�(F 2)] = 0.018wR(F 2) = 0.060S = 1.33222 reflections24 parameters

1 restraintOnly H-atom coordinates refined��max = 1.07 e A�3

��min = �0.57 e A�3

Studies of several single crystals of Ba[Co3(VO4)2(OH)2] all

revealed the same metrically hexagonal unit cell. A crystal exhibiting

sharp reflection spots was chosen for the data collection. The H atom

was located from a difference Fourier map and refined with the O—H

bond length restrained to 0.82 (2) A, and with Uiso(H) = 1.5Ueq(O).

Data collection: COLLECT (Nonius, 2002); cell refinement:

SCALEPACK (Otwinowski & Minor, 1997); data reduction:

DENZO-SMN (Otwinowski et al., 2003); program(s) used to solve

structure: SIR97 (Altomare et al., 1999); program(s) used to refine

structure: WinGX (Farrugia, 2012) and SHELXL97 (Sheldrick,

2008); molecular graphics: ATOMS (Dowty, 2000); software used to

prepare material for publication: publCIF (Westrip, 2010).

The authors gratefully acknowledge financial support from

the Austrian Science Foundation (FWF) (grant No. V203-

N19) and the Ministry of Education, Science and Technolo-

gical Development of the Republic of Serbia (grant No.

III45007).

Supplementary data for this paper are available from the IUCr electronicarchives (Reference: BI3052). Services for accessing these data aredescribed at the back of the journal.

References

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inorganic compounds

Acta Cryst. (2013). C69, 114–118 Ðordevic and Karanovic � Ba[Co3(VO4)2(OH)2] 117

Table 1Selected bond lengths (A).

Ba1—O2i 2.824 (3)Ba1—O2ii 2.824 (3)Ba1—O2iii 2.824 (3)Ba1—O2iv 2.824 (3)Ba1—O2v 2.824 (3)Ba1—O2 2.824 (3)Ba1—O1iii 3.4186 (5)Ba1—O1vi 3.4186 (5)Ba1—O1 3.4186 (5)Ba1—O1vii 3.4186 (5)Ba1—O1viii 3.4186 (5)Ba1—O1ix 3.4186 (5)

Co1—O3x 1.9449 (19)Co1—O3 1.9449 (19)Co1—O2x 2.161 (2)Co1—O2xi 2.161 (2)Co1—O2 2.161 (2)Co1—O2v 2.161 (2)Co1—Co1iv 2.9605 (4)V1—O1 1.661 (6)V1—O2xii 1.745 (3)V1—O2iv 1.745 (3)V1—O2xiii 1.745 (3)

Symmetry codes: (i) yþ 13;�xþ yþ 2

3;�zþ 53; (ii) x� yþ 1

3; x� 13;�zþ 5

3; (iii)�x þ 4

3;�yþ 23;�zþ 5

3; (iv) �y þ 1; x� y; z; (v) �xþ yþ 1;�xþ 1; z; (vi)�x þ 1

3;�y� 13;�zþ 5

3; (vii) xþ 1; yþ 1; z; (viii) x; yþ 1; z; (ix) �xþ 43;�y� 1

3,�z þ 5

3; (x) �xþ 53;�yþ 4

3, �zþ 43; (xi) x� yþ 2

3; xþ 13;�zþ 4

3; (xii) �x þ y;�x; z;(xiii) x; y� 1; z.

Table 2Hydrogen-bond geometry (A, �).

D—H� � �A D—H H� � �A D� � �A D—H� � �A

O3—H1� � �O1iii 0.81 (2) 1.79 (2) 2.596 (7) 180

Symmetry code: (iii) �xþ 43;�yþ 2

3;�zþ 53.

Table 3Unit-cell parameters of some M1[M23(XO4)2(OH)3] compounds (M1 = Ba, Pb; M2 = Co, Cu; X = V, As).

Compound a (A) b (A) c (A) � (�) � (�) � (�) V (A3) Reference

Ba[Co3(VO4)2(OH)2] 5.9210 (8) 5.9210 (8) 21.016 (4) 90 90 120 638.07 (18) This workBa[Cu3(VO4)2(OH)2] 10.270 (2) 5.9110 (10) 7.711 (2) 90 116.42 (3) 90 419.21 (15) Ma et al. (1991)Transformed cell† 5.911 5.925 20.7171 90.06 90 119.92 628.8Pb[Cu3(AsO4)2(OH)2] 10.147 (2) 5.8920 (10) 14.081 (2) 90 106.050 (10) 90 809.0 (2) Ghose & Wan (1979)Transformed cell‡ 5.892 5.867 20.313 91.87 90 120.14 606.8

† Transformation matrix: 0 1 0/12

12 0/1 0 3. ‡ Transformation matrix: 0 1 0/1

212 0/1

2 0 32.

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inorganic compounds

118 Ðordevic and Karanovic � Ba[Co3(VO4)2(OH)2] Acta Cryst. (2013). C69, 114–118

supplementary materials

sup-1Acta Cryst. (2013). C69, 114-118

supplementary materials

Acta Cryst. (2013). C69, 114-118 [doi:10.1107/S0108270113001972]

Ba[Co3(VO4)2(OH)2] with a regular Kagomé lattice

Tamara Đordević and Ljiljana Karanović

Barium di-µ-hydroxydo-di-µ-vanadato-tricobaltate(II)

Crystal data

Ba[Co3(VO4)2(OH)2]Mr = 578.03Rhombohedral, R3mHall symbol: -R 3 2"a = 5.9210 (8) Åc = 21.016 (4) Åα = 90°γ = 120°V = 638.07 (18) Å3

Z = 3

F(000) = 795Dx = 4.513 Mg m−3

Mo Kα radiation, λ = 0.71069 ÅCell parameters from 4406 reflectionsθ = 0.4–32.6°µ = 12.42 mm−1

T = 298 KNeedle-like, light pink0.07 × 0.06 × 0.04 mm

Data collection

Nonius KappaCCD area-detector diffractometer

Radiation source: fine-focus sealed tubeGraphite monochromatorφ and ω scansAbsorption correction: multi-scan

(Otwinowski et al., 2003)Tmin = 0.477, Tmax = 0.637

1909 measured reflections222 independent reflections215 reflections with I > 2σ(I)Rint = 0.023θmax = 27.8°, θmin = 2.9°h = −7→7k = −7→7l = −27→27

Refinement

Refinement on F2

Least-squares matrix: fullR[F2 > 2σ(F2)] = 0.018wR(F2) = 0.060S = 1.33222 reflections24 parameters1 restraintPrimary atom site location: structure-invariant

direct methodsSecondary atom site location: difference Fourier

map

Hydrogen site location: inferred from neighbouring sites

Only H-atom coordinates refinedw = 1/[σ2(Fo

2) + (0.0326P)2 + 3.6751P] where P = (Fo

2 + 2Fc2)/3

(Δ/σ)max < 0.001Δρmax = 1.07 e Å−3

Δρmin = −0.57 e Å−3

Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4

Extinction coefficient: 0.0017 (5)

supplementary materials

sup-2Acta Cryst. (2013). C69, 114-118

Special details

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. Several crystals of the title compound were selected for single-crystal studies with a Nonius KappaCCD single-crystal four-circle diffractometer [Mo tube, graphite monochromator, CCD detector frame size: 621×576 pixels (binned mode)], equipped with a 300 µm diameter capillary-optics collimator. A complete sphere of reciprocal space (φ and ω scans) was measured at room temperature for a suitable crystal. The intensity data were processed with the Nonius program suite DENZO-SMN (Otwinowski & Minor, 1997) and corrected for Lorentz, polarization and background effects by the multi-scan method (Otwinowski & Minor, 1997; Otwinowski et al., 2003) for absorption. The data were processed with WinGX (Farrugia, 1999) and SHELXL97 (Sheldrick, 2008). 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)

x y z Uiso*/Ueq

Ba1 0.6667 0.3333 0.8333 0.0213 (3)Co1 0.8333 0.6667 0.6667 0.0108 (3)V1 0.3333 −0.3333 0.75329 (5) 0.0072 (3)O1 0.3333 −0.3333 0.8323 (3) 0.0281 (14)O2 0.4955 (3) 0.5045 (3) 0.72806 (14) 0.0110 (6)O3 1.0000 1.0000 0.71082 (19) 0.0053 (9)H1 1.0000 1.0000 0.7494 (10) 0.008*

Atomic displacement parameters (Å2)

U11 U22 U33 U12 U13 U23

Ba1 0.0276 (3) 0.0276 (3) 0.0086 (4) 0.01379 (17) 0.000 0.000Co1 0.0116 (4) 0.0090 (4) 0.0111 (4) 0.0045 (2) −0.00055 (13) −0.0011 (3)V1 0.0078 (4) 0.0078 (4) 0.0060 (5) 0.0039 (2) 0.000 0.000O1 0.038 (2) 0.038 (2) 0.008 (2) 0.0191 (11) 0.000 0.000O2 0.0104 (10) 0.0104 (10) 0.0128 (13) 0.0055 (10) 0.0005 (5) −0.0005 (5)O3 0.0062 (13) 0.0062 (13) 0.004 (2) 0.0031 (7) 0.000 0.000

Geometric parameters (Å, º)

Ba1—O2i 2.824 (3) Co1—O3 1.9449 (19)Ba1—O2ii 2.824 (3) Co1—O2x 2.161 (2)Ba1—O2iii 2.824 (3) Co1—O2xi 2.161 (2)Ba1—O2iv 2.824 (3) Co1—O2 2.161 (2)Ba1—O2v 2.824 (3) Co1—O2v 2.161 (2)Ba1—O2 2.824 (3) Co1—Co1iv 2.9605 (4)Ba1—O1iii 3.4186 (5) V1—O1 1.661 (6)Ba1—O1vi 3.4186 (5) V1—O2xii 1.745 (3)Ba1—O1 3.4186 (5) V1—O2iv 1.745 (3)Ba1—O1vii 3.4186 (5) V1—O2xiii 1.745 (3)Ba1—O1viii 3.4186 (5) O3—O1iii 2.596 (7)

supplementary materials

sup-3Acta Cryst. (2013). C69, 114-118

Ba1—O1ix 3.4186 (5) O3—H1 0.81 (2)Co1—O3x 1.9449 (19)

O2i—Ba1—O2ii 65.14 (9) O3—Co1—O2v 93.05 (9)O2i—Ba1—O2iii 65.14 (9) O2x—Co1—O2v 90.54 (15)O2ii—Ba1—O2iii 65.14 (9) O2xi—Co1—O2v 179.998 (2)O2i—Ba1—O2iv 179.999 (1) O2—Co1—O2v 89.46 (15)O2ii—Ba1—O2iv 114.86 (10) O3x—Co1—Co1xiv 139.56 (7)O2iii—Ba1—O2iv 114.86 (9) O3—Co1—Co1xiv 40.44 (7)O2i—Ba1—O2v 114.86 (10) O2x—Co1—Co1xiv 46.75 (5)O2ii—Ba1—O2v 180.00 (10) O2xi—Co1—Co1xiv 91.07 (7)O2iii—Ba1—O2v 114.86 (9) O2—Co1—Co1xiv 133.25 (5)O2iv—Ba1—O2v 65.14 (9) O2v—Co1—Co1xiv 88.93 (6)O2i—Ba1—O2 114.86 (9) O3x—Co1—Co1xv 139.56 (7)O2ii—Ba1—O2 114.86 (9) O3—Co1—Co1xv 40.44 (7)O2iii—Ba1—O2 180.0 O2x—Co1—Co1xv 91.07 (6)O2iv—Ba1—O2 65.14 (9) O2xi—Co1—Co1xv 46.75 (5)O2v—Ba1—O2 65.14 (9) O2—Co1—Co1xv 88.93 (6)O2i—Ba1—O1iii 51.20 (11) O2v—Co1—Co1xv 133.25 (5)O2ii—Ba1—O1iii 107.81 (8) Co1xiv—Co1—Co1xv 60.0O2iii—Ba1—O1iii 107.81 (8) O1—V1—O2xii 107.69 (10)O2iv—Ba1—O1iii 128.80 (11) O1—V1—O2iv 107.69 (10)O2v—Ba1—O1iii 72.19 (8) O2xii—V1—O2iv 111.20 (9)O2—Ba1—O1iii 72.19 (8) O1—V1—O2xiii 107.69 (10)O2i—Ba1—O1vi 107.81 (8) O2xii—V1—O2xiii 111.20 (9)O2ii—Ba1—O1vi 51.20 (11) O2iv—V1—O2xiii 111.20 (9)O2iii—Ba1—O1vi 107.81 (8) O1—V1—Co1xii 121.589 (17)O2iv—Ba1—O1vi 72.19 (8) O2xii—V1—Co1xii 30.46 (5)O2v—Ba1—O1vi 128.80 (11) O2iv—V1—Co1xii 122.94 (9)O2—Ba1—O1vi 72.19 (8) O2xiii—V1—Co1xii 80.84 (5)O1iii—Ba1—O1vi 119.997 (2) V1—O1—Ba1 90.36 (9)O2i—Ba1—O1 128.80 (11) V1—O1—Ba1xvi 90.36 (9)O2ii—Ba1—O1 72.19 (8) Ba1—O1—Ba1xvi 119.996 (2)O2iii—Ba1—O1 72.19 (8) V1—O1—Ba1xiii 90.36 (9)O2iv—Ba1—O1 51.20 (11) Ba1—O1—Ba1xiii 119.996 (2)O2v—Ba1—O1 107.81 (8) Ba1xvi—O1—Ba1xiii 119.996 (2)O2—Ba1—O1 107.81 (8) V1viii—O2—Co1 125.37 (10)O1iii—Ba1—O1 180.0 V1viii—O2—Co1iv 125.37 (10)O1vi—Ba1—O1 60.004 (3) Co1—O2—Co1iv 86.49 (10)O2i—Ba1—O1vii 72.19 (8) V1viii—O2—Ba1 110.75 (13)O2ii—Ba1—O1vii 128.80 (11) Co1—O2—Ba1 102.04 (9)O2iii—Ba1—O1vii 72.19 (8) Co1iv—O2—Ba1 102.04 (9)O2iv—Ba1—O1vii 107.81 (8) V1viii—O2—Co1xvii 70.84 (6)O2v—Ba1—O1vii 51.20 (11) Co1—O2—Co1xvii 122.49 (11)O2—Ba1—O1vii 107.81 (8) Co1iv—O2—Co1xvii 54.58 (4)O1iii—Ba1—O1vii 60.004 (3) Ba1—O2—Co1xvii 124.25 (4)O1vi—Ba1—O1vii 180.0 V1viii—O2—Co1xv 70.84 (6)O1—Ba1—O1vii 119.996 (2) Co1—O2—Co1xv 54.58 (4)O2i—Ba1—O1viii 72.19 (8) Co1iv—O2—Co1xv 122.49 (11)

supplementary materials

sup-4Acta Cryst. (2013). C69, 114-118

O2ii—Ba1—O1viii 72.19 (8) Ba1—O2—Co1xv 124.25 (4)O2iii—Ba1—O1viii 128.80 (11) Co1xvii—O2—Co1xv 109.18 (7)O2iv—Ba1—O1viii 107.81 (8) Co1—O3—Co1xv 99.12 (13)O2v—Ba1—O1viii 107.81 (8) Co1—O3—Co1xiv 99.12 (13)O2—Ba1—O1viii 51.20 (11) Co1xv—O3—Co1xiv 99.12 (13)O1iii—Ba1—O1viii 60.004 (3) Co1—O3—Ba1viii 129.65 (4)O1vi—Ba1—O1viii 60.004 (3) Co1xv—O3—Ba1viii 65.48 (6)O1—Ba1—O1viii 119.996 (3) Co1xiv—O3—Ba1viii 129.65 (4)O1vii—Ba1—O1viii 119.996 (3) Co1—O3—Ba1vii 129.65 (4)O2i—Ba1—O1ix 107.81 (8) Co1xv—O3—Ba1vii 129.65 (4)O2ii—Ba1—O1ix 107.81 (8) Co1xiv—O3—Ba1vii 65.48 (6)O2iii—Ba1—O1ix 51.20 (11) Ba1viii—O3—Ba1vii 87.54 (6)O2iv—Ba1—O1ix 72.19 (8) Co1—O3—Ba1 65.48 (6)O2v—Ba1—O1ix 72.19 (8) Co1xv—O3—Ba1 129.65 (4)O2—Ba1—O1ix 128.80 (11) Co1xiv—O3—Ba1 129.65 (4)O1iii—Ba1—O1ix 119.996 (3) Ba1viii—O3—Ba1 87.54 (6)O1vi—Ba1—O1ix 119.996 (3) Ba1vii—O3—Ba1 87.54 (6)O1—Ba1—O1ix 60.004 (2) Co1—O3—Ba1xviii 61.50 (10)O1vii—Ba1—O1ix 60.004 (2) Co1xv—O3—Ba1xviii 61.50 (10)O1viii—Ba1—O1ix 180.0 Co1xiv—O3—Ba1xviii 61.50 (10)O3x—Co1—O3 179.999 (1) Ba1viii—O3—Ba1xviii 126.99 (4)O3x—Co1—O2x 93.05 (9) Ba1vii—O3—Ba1xviii 126.99 (4)O3—Co1—O2x 86.95 (9) Ba1—O3—Ba1xviii 126.99 (4)O3x—Co1—O2xi 93.05 (9) Co1—O3—H1 118.50 (10)O3—Co1—O2xi 86.95 (9) Co1xv—O3—H1 118.50 (10)O2x—Co1—O2xi 89.46 (15) Co1xiv—O3—H1 118.50 (11)O3x—Co1—O2 86.95 (9) Ba1viii—O3—H1 53.01 (4)O3—Co1—O2 93.05 (9) Ba1vii—O3—H1 53.01 (5)O2x—Co1—O2 180.0 Ba1—O3—H1 53.01 (4)O2xi—Co1—O2 90.54 (15) Ba1xviii—O3—H1 180.000 (9)O3x—Co1—O2v 86.95 (9)

Symmetry codes: (i) y+1/3, −x+y+2/3, −z+5/3; (ii) x−y+1/3, x−1/3, −z+5/3; (iii) −x+4/3, −y+2/3, −z+5/3; (iv) −y+1, x−y, z; (v) −x+y+1, −x+1, z; (vi) −x+1/3, −y−1/3, −z+5/3; (vii) x+1, y+1, z; (viii) x, y+1, z; (ix) −x+4/3, −y−1/3, −z+5/3; (x) −x+5/3, −y+4/3, −z+4/3; (xi) x−y+2/3, x+1/3, −z+4/3; (xii) −x+y, −x, z; (xiii) x, y−1, z; (xiv) −y+2, x−y+1, z; (xv) −x+y+1, −x+2, z; (xvi) x−1, y−1, z; (xvii) −x+y, −x+1, z; (xviii) x+1/3, y+2/3, z−1/3.

Hydrogen-bond geometry (Å, º)

D—H···A D—H H···A D···A D—H···A

O3—H1···O1iii 0.81 (2) 1.79 (2) 2.596 (7) 180

Symmetry code: (iii) −x+4/3, −y+2/3, −z+5/3.

Unit-cell parameters of some M1[M23(XO4)2(OH)3] compounds (M1 = Ba, Pb; M2 = Co, Cu; X = V, As)

Compound a (Å) b (Å) c (Å) α (°) β (°) γ (°) V (Å3) Reference

Ba[Co3(VO4)2(OH)2] 5.9210 (8) 5.9210 (8) 21.016 (4) 90 90 120 638.07 (18)This work

Ba[Cu3(VO4)2(OH)2] 10.270 (2) 5.9110 (10) 7.711 (2) 90 116.42 (3) 90 419.21 (15)Ma et al. (1991)

Transformed cell# 5.911 5.925 20.7171 90.06 90 119.92 628.8

supplementary materials

sup-5Acta Cryst. (2013). C69, 114-118

Pb[Cu3(AsO4)2(OH)2]10.147 (2) 5.8920 (10) 14.081 (2) 90 106.050 (10) 90 809.0 (2)Ghose & Wan (1979)

Transformed cell* 5.892 5.867 20.313 91.87 90 120.14 606.8

Notes: (#) transformation matrix: 010/0.5 0.5 0/103; (*) transformation matrix: 010/0.5 0.5 0/0.5 0 1.5.