Poly[μ-aqua-diaqua-μ₄-malonato-μ₃-malonato-barium(II)nickel(II)]

The title complex, [BaNi(C₃H₂O₄)₂(H₂O)₃]_n, is polymeric, with two non-equivalent malonate dianions bridging one Ni atom and five different Ba atoms. The Ni atoms have a distorted octa­hedral (NiO₆) environment, and are coordinated by four malonate O atoms in a planar arrangement and two water mol­ecules in axial positions. The Ba atom may be described as a BaO₉ polyhedron in a monocapped square-anti­prismatic environment, which involves two water mol­ecules and seven O atoms from different malonate ligands. The three-dimensional structure is further maintained and stabilized by hydrogen bonds.

S1. Comment

Heterobimetallic malonate complexes involving transition and alkaline-earth metals have attracted much attention recently in the area of topology design and for their potential applications in molecular-based magnetism, catalysis, supramolecular chemistry and materials science (Gil de Muro et al., 1998, 2004; Fu et al., 2006). The use of dicarboxylate ligands as small building blocks to generate metal-organic frameworks of different dimensionalities may lead to interesting network architectures (Rodriguez-Martin et al., 2002). From a coordination standpoint, the malonate ligand, with two neighboring carboxylate groups, is a very flexible ligand. Its basic coordination mode is as a chelate via two distal carboxylate O atoms to form a six-membered ring and the coordinating ability of the nonchelating O atoms makes the formation of polymeric networks possible (Djeghri et al., 2005, 2006). In the course of our study of heterobimetallic malonate complexes involving transition and alkaline-earth metals, we have recently reported the crystal structures of poly[tetraaqua-di-µ₄-malonato-barium(II)zinc(II)] (Guo & Guo, 2006) and poly[tetra-µ-aqua-hexaaquadi-µ₃-malonato-dinitratodibarium(II)nickel(II)] (Guo & Cao, 2006). Interestingly, when nickel chloride was used in an attempt to obtain a product similar or isotypic to that of the zinc compound, a completly different crystal structure was obtained. We report here the structure of the bimetallic malonate complex (I).

The asymmetric unit of (I) comprises one Ni atom, one Ba atom, two complete malonate dianions (C1–C3/O1–O4 and C4–C6/O5–O8) and three non-equivalent water molecules (O9–O11), and is shown in Fig. 1 in a symmetry-expanded view that displays the full coordination of the Ba and Ni atoms. Selected geometric parameters are given in Table 1.

The Ba atom is surrounded by an O₉ donor set in an approximate monocapped square antiprismatic environment (Fig. 1). The four coordination sites of the basal plane are occupied by atoms O6ⁱⁱⁱ from a malonate dianion, O4^iv from a second malonate ligand and two coordinated water molecules (O11 and O11ⁱ). The opposite plane contains two O atoms (O1 and O5) from two malonate ligands, a bridging O atom (O4ⁱⁱ) from a third malonate ligand and a chelating carboxylate O atom (O7^v) from a fourth malonate ligand (see Fig. 1 for symmetry codes). Finally, the capping site is occupied by the chelating atom O8^v. Of the Ba—O distances (Table 1), Ba—O7^v and Ba—O8^v are the longest, probably as a result of strain in the four-membered chelate. The Ba—O(water) bonds are slightly shorter than those in [Ba₂Ni(C₃H₂O₄)₂(NO₃)₂(H₂O)₁₀] (Guo & Cao, 2006), while the Ba—O(malonate) bond distances correspond well with the sum of the ionic radii [1.21 + 1.66 = 2.87 Å for 10-coordinate Ba²⁺ ions; Bauer et al., 2005] and are comparable to the values reported for barium oxydiacetates (Baggio et al. 2004). The BaO₉ polyhedra share edges to form zigzag chains propagated in the c direction via pairs of water bridges (O11 and O11ⁱ) or bridging malonate O4ⁱⁱ and O4^iv atoms. This results in Ba1···Ba1ⁱ separations of 4.3362 (8) Å.

The Ni atom has octahedral coordination, with atoms O1, O3, O5 and O7 of two non-equivalent malonate dianions in a planar arrangement, and atoms O9 and O10 from two water molecules in a trans conformation. The Ni—O(water) bonds are slightly longer while the Ni—O(malonate) bonds are somewhat shorter than those in [CaNi(mal)₂(H₂O)₄]·2H₂O (Gil de Muro et al., 2000). Thus, the coordination octahedra of the Ni atoms can be visualized as having a slightly elongated axial distortion.

Also evident in Fig. 1 is the variability of the coordination modes of the malonate ligand. Monodentate, bidentate chelating, chelated six-membered and bridging coordination modes are all present. In the case of the C1–C3/O1–O4 malonate dianion, atom O1 adopts both a monodentate mode bonding to Ni and a bridging bonding mode to Ni and Ba. Atom O4 adopts a bridging mode to connect two Ba atoms. Furthermore, two carboxyl groups (atoms O1 and O3) adopt a six-membered chelating mode, forming a ring around Ni with an envelope conformation, with arom C2 displaced by 0.65 Å from the plane defined by the other atoms in the ring. For the C4–C6/O5–O8 malonate dianion, the coordination modes of atom O5 are the same as for atom O1; atom O6 adopts a monodentate mode, coordinating another Ba atom. Atoms O7 and O8 from the same carboxyl function chelate the Ba atom at (x - 1/2, -y + 3/2, z - 1/2) to form a four-membered ring. Atoms O7 and O5 from different carboxyl groups form a six-membered chelate (Ni1/O5/C4–C6/O7) with a boat conformation; atoms Ni1 and C5 lie 0.52 and 0.42 Å, respectively, out of the O5/C4/C6/O7 plane. The Ni1···Ba1 separation of 3.8059 (14) Å, mediated by the O1,O5 double bridge, is much less than the sum of their van der Waals radii (2.30 + 2.14 = 4.44 Å). This suggests some degree of interaction between the Ni and Ba atoms.

The structure as a whole consists of two distinct types of layer (Fig. 2), both perpendicular to [100] and stacked alternately in the a direction. The first of these (Fig. 3) is composed entirely of Ni atoms, malonate dianions and water molecules (O9, O10). Hydrogen bonding plays an important role in the stabilization of the extended layers. The noncoordinated O2 atom is involved in forming strong hydrogen bonds (O9—H9A···O2^vi; symmetry codes as in Table 2) (Brown, 1976). Within this layer, and along the c direction, O9—H9A···O2^vi and O10—H10A···O8^vii hydrogen bonds are responsible for the formation of a 12-membered hydrogen-bonded R₂²(12) ring (Bernstein et al., 1995). In the b direction, the neighbouring Ni coordination octahedra are linked together via O10—H10B···O6ⁱⁱⁱ hydrogen bonds and 14-membered hydrogen-bonded R₂²(14) rings. In this way, a complete two-dimensional connectivity is achieved parallel to the bc plane.

The other type of layer, type 2, consists of Ba atoms and water molecules (Fig. 2). In the crystallographic a direction, the connectivity of two layers is achieved by means of O1, O5 and O7 bridging atoms and O6—C4—O5, O4—C3—O3 and O8—C6—O7 bridges between Ni1 coordination octahedra and neighbouring BaO₉ polyhedra. At the same time, the zigzag BaO₉ polyhedral chains in the c direction are linked into layers and complete the three-dimensional connectivity of the structure. The interlayer connectivity is further enhanced by hydrogen bonds of the form O11—H11A···O3^v and O11—H11B···O2 (Table 2).

Related literature

For related literature, see: Bauer et al. (2005); Bernstein et al. (1995); Brown (1976); Fu et al. (2006); Gil de Muro, Insausti, Lezama, Urtiaga, Arriortua & Rojo (2000); Gil de Muro, Lezama, Insausti & Rojo (2004); Gil de Muro, Mautner, Insausti, Lezama & Rojo (1998); Guo & Cao (2006); Guo & Guo (2006); Rodriguez-Martin, Hernandez-Molina, Delgado, Pasan, Ruiz-Perez, Sanchiz, Lloretc & Julvec (2002).

S2. Experimental

The title complex was prepared under continuous stirring with successive addition of malonic acid (0.31 g, 3 mmol), NiCl₂·6H₂O (0.47 g, 2 mmol),and Ba(OH)₂·8H₂O (0.63 g, 2 mmol) to distilled water (20 ml) at room temperature. After filtration, slow evaporation over a period of 3 d at room temperature provided green needle crystals of (I).

S3. Refinement

All difference peaks larger than 1.0 e Å^-3 are around atom Ba1. The highest difference peak lies 0.85 Å from atom Ba1. All H atoms attached to O atoms were found in difference Fourier maps. During refinement, the H atoms were fixed at O—H distances of 0.85 Å and their U_iso(H) values were set at 1.2U_eq(O). H atoms of CH₂ groups were treated as riding [C—H = 0.97 Å and U_iso(H) = 1.2U_eq(C)].

Computing details

Data collection: CrystalClear (Rigaku/MSC, 2005); cell refinement: CrystalClear (Rigaku/MSC, 2005); data reduction: CrystalClear (Rigaku/MSC, 2005); program(s) used to solve structure: SHELXTL (Bruker, 2001); program(s) used to refine structure: SHELXTL (Bruker, 2001); molecular graphics: SHELXTL (Bruker, 2001); software used to prepare material for publication: SHELXTL (Bruker, 2001).

Figures

	Fig. 1. A view of the structure of (I), showing the atom-numbering scheme and coordination polyhedra for Ni and Ba atoms; displacement ellipsoids were drawn at the 30% probability level. [Symmetry codes: (i) x, -y + 1, z - 1/2; (ii) x + 1/2, -y + 3/2, z - 1/2; (iii) x, -y + 1, z + 1/2; (iv) x + 1/2, y - 1/2, z; (v) x + 1/2, -y + 3/2, z + 1/2.]
	Fig. 2. The packing of (I), showing hydrogen-bonding interactions within a type 1 layer parallel to the bc plane, viewed down the a axis.
	Fig. 3. The packing of (I), viewed down the b axis, showing the alternation of type 1 and type 2 layers along the a axis.

Poly[µ-aqua-diaqua-µ₄-malonato-µ₃-malonato-barium(II)nickel(II)]

Crystal data

[BaNi(C3H2O4)2(H2O)3]	F(000) = 872
Mr = 454.19	Dx = 2.504 Mg m^−3
Monoclinic, Cc	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: C -2yc	Cell parameters from 2018 reflections
a = 12.177 (2) Å	θ = 2.9–27.9°
b = 13.842 (3) Å	µ = 4.86 mm^−1
c = 7.1502 (14) Å	T = 294 K
β = 91.17 (3)°	Needle, green
V = 1204.9 (4) Å^3	0.12 × 0.10 × 0.06 mm
Z = 4

Data collection

Rigaku Saturn diffractometer	1432 independent reflections
Radiation source: fine-focus sealed tube	1424 reflections with I > 2σ(I)
Confocal monochromator	Rint = 0.026
Detector resolution: 28.676 pixels mm^-1	θmax = 25.0°, θmin = 2.9°
ω scans	h = −12→14
Absorption correction: multi-scan (Jacobson, 1998)	k = −16→16
Tmin = 0.558, Tmax = 0.738	l = −7→8
3369 measured reflections

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.042	H-atom parameters constrained
wR(F^2) = 0.099	w = 1/[σ^2(Fo^2) + (0.0834P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 1.09	(Δ/σ)max < 0.001
1432 reflections	Δρmax = 1.23 e Å^−3
173 parameters	Δρmin = −0.65 e Å^−3
2 restraints	Absolute structure: Flack (1983), 365 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.18 (6)

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. 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 (Ų)

	x	y	z	Uiso*/Ueq
Ba1	1.09630 (6)	0.58864 (3)	0.08472 (7)	0.0509 (2)
Ni1	0.85771 (10)	0.75456 (8)	−0.04657 (15)	0.0512 (3)
O1	0.9631 (6)	0.7449 (5)	0.1789 (11)	0.0559 (16)
O2	0.9781 (7)	0.7695 (6)	0.4821 (11)	0.0636 (18)
O3	0.7784 (6)	0.8606 (5)	0.0811 (9)	0.0552 (15)
O4	0.7371 (6)	0.9655 (5)	0.3024 (10)	0.0556 (14)
O5	0.9218 (6)	0.6344 (5)	−0.1662 (10)	0.0544 (14)
O6	0.8982 (5)	0.4912 (5)	−0.2985 (10)	0.0557 (14)
O7	0.7548 (6)	0.7731 (5)	−0.2746 (11)	0.0547 (15)
O8	0.6865 (6)	0.7295 (5)	−0.5471 (11)	0.0574 (16)
O9	0.9735 (6)	0.8426 (5)	−0.1723 (11)	0.0559 (14)
H9A	0.9638	0.8268	−0.2864	0.067*
H9B	1.0392	0.8419	−0.1299	0.067*
O10	0.7560 (6)	0.6563 (5)	0.0964 (10)	0.0553 (15)
H10A	0.7326	0.6906	0.1855	0.066*
H10B	0.7977	0.6092	0.1251	0.066*
O11	1.0786 (7)	0.5978 (4)	0.4634 (13)	0.0568 (16)
H11A	1.1443	0.6011	0.5063	0.068*
H11B	1.0375	0.6461	0.4850	0.068*
C1	0.9578 (8)	0.7975 (7)	0.3218 (16)	0.054 (2)
C2	0.9203 (12)	0.9001 (8)	0.295 (2)	0.065 (3)
H2A	0.9267	0.9336	0.4143	0.078*
H2B	0.9687	0.9319	0.2087	0.078*
C3	0.8056 (9)	0.9090 (6)	0.2238 (17)	0.052 (2)
C4	0.8685 (9)	0.5759 (7)	−0.2656 (16)	0.052 (2)
C5	0.7550 (11)	0.6044 (8)	−0.349 (2)	0.065 (3)
H5A	0.7437	0.5679	−0.4633	0.078*
H5B	0.6998	0.5830	−0.2621	0.078*
C6	0.7321 (8)	0.7106 (8)	−0.3936 (15)	0.055 (2)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Ba1	0.0510 (3)	0.0496 (3)	0.0522 (3)	−0.0004 (2)	0.00175 (19)	0.0002 (2)
Ni1	0.0525 (6)	0.0502 (5)	0.0509 (7)	0.0025 (4)	0.0007 (5)	−0.0013 (5)
O1	0.059 (4)	0.059 (4)	0.050 (4)	0.008 (3)	−0.003 (3)	−0.001 (3)
O2	0.060 (4)	0.076 (4)	0.054 (4)	0.015 (3)	0.000 (3)	−0.002 (3)
O3	0.058 (3)	0.052 (3)	0.055 (4)	0.010 (3)	0.003 (3)	−0.002 (3)
O4	0.060 (3)	0.056 (3)	0.052 (3)	0.006 (3)	0.004 (3)	0.005 (3)
O5	0.058 (3)	0.049 (3)	0.055 (4)	0.002 (3)	−0.004 (3)	0.001 (3)
O6	0.051 (3)	0.054 (3)	0.062 (4)	0.004 (3)	0.002 (3)	−0.001 (3)
O7	0.056 (4)	0.050 (3)	0.058 (4)	0.007 (3)	−0.001 (3)	0.001 (3)
O8	0.052 (4)	0.060 (4)	0.060 (4)	0.008 (3)	−0.005 (3)	−0.007 (3)
O9	0.058 (4)	0.057 (3)	0.053 (3)	−0.001 (3)	0.004 (3)	−0.001 (3)
O10	0.060 (4)	0.052 (3)	0.054 (4)	0.003 (3)	0.005 (3)	−0.002 (3)
O11	0.054 (4)	0.050 (3)	0.067 (4)	0.003 (2)	−0.002 (3)	0.002 (3)
C1	0.051 (5)	0.057 (5)	0.054 (5)	0.006 (4)	0.000 (4)	−0.005 (4)
C2	0.070 (7)	0.059 (6)	0.066 (7)	0.000 (4)	0.002 (6)	−0.010 (5)
C3	0.052 (6)	0.049 (5)	0.056 (6)	0.000 (3)	0.007 (5)	0.003 (3)
C4	0.049 (5)	0.053 (4)	0.053 (6)	0.001 (3)	0.001 (4)	0.001 (4)
C5	0.061 (6)	0.060 (5)	0.075 (7)	0.006 (5)	−0.009 (5)	−0.001 (5)
C6	0.047 (4)	0.064 (5)	0.055 (5)	−0.001 (4)	0.001 (4)	−0.003 (5)

Geometric parameters (Å, º)

Ba1—O11	2.724 (10)	O4—C3	1.281 (12)
Ba1—O11^i	2.729 (6)	O5—C4	1.251 (13)
Ba1—O4^ii	2.778 (7)	O6—C4	1.250 (12)
Ba1—O1	2.794 (7)	O7—C6	1.241 (13)
Ba1—O6^iii	2.796 (6)	O8—C6	1.247 (13)
Ba1—O5	2.825 (7)	O9—H9A	0.8505
Ba1—O4^iv	2.857 (7)	O9—H9B	0.8495
Ba1—O7^v	2.885 (7)	O10—H10A	0.8486
Ba1—O8^v	2.911 (7)	O10—H10B	0.8495
Ba1—Ni1	3.8059 (14)	O11—H11A	0.8518
Ba1—Ba1^i	4.3362 (8)	O11—H11B	0.8524
Ni1—O3	1.989 (6)	C1—C2	1.503 (15)
Ni1—O5	2.033 (7)	C2—C3	1.482 (19)
Ni1—O1	2.045 (8)	C2—H2A	0.9700
Ni1—O7	2.052 (8)	C2—H2B	0.9700
Ni1—O9	2.082 (7)	C4—C5	1.545 (17)
Ni1—O10	2.117 (7)	C5—C6	1.528 (16)
O1—C1	1.257 (14)	C5—H5A	0.9700
O2—C1	1.230 (14)	C5—H5B	0.9700
O3—C3	1.259 (14)
O11—Ba1—O11^i	110.6 (2)	O1—Ni1—O10	86.7 (3)
O11—Ba1—O4^ii	142.9 (2)	O7—Ni1—O10	96.3 (3)
O11^i—Ba1—O4^ii	63.9 (2)	O9—Ni1—O10	173.2 (3)
O11—Ba1—O1	70.5 (2)	C1—O1—Ni1	124.1 (6)
O11^i—Ba1—O1	140.0 (3)	C1—O1—Ba1	133.1 (6)
O4^ii—Ba1—O1	138.9 (2)	Ni1—O1—Ba1	102.6 (3)
O11—Ba1—O6^iii	68.6 (2)	C3—O3—Ni1	129.9 (7)
O11^i—Ba1—O6^iii	70.0 (2)	C3—O4—Ba1^vi	124.8 (6)
O4^ii—Ba1—O6^iii	131.3 (2)	C3—O4—Ba1^vii	120.9 (7)
O1—Ba1—O6^iii	74.1 (2)	Ba1^vi—O4—Ba1^vii	100.6 (2)
O11—Ba1—O5	123.2 (2)	C4—O5—Ni1	124.7 (7)
O11^i—Ba1—O5	87.5 (2)	C4—O5—Ba1	126.2 (6)
O4^ii—Ba1—O5	93.8 (2)	Ni1—O5—Ba1	101.9 (3)
O1—Ba1—O5	63.0 (2)	C4—O6—Ba1^i	133.0 (6)
O6^iii—Ba1—O5	68.7 (2)	C6—O7—Ni1	125.6 (7)
O11—Ba1—O4^iv	62.9 (2)	C6—O7—Ba1^viii	94.9 (6)
O11^i—Ba1—O4^iv	69.6 (2)	Ni1—O7—Ba1^viii	138.9 (3)
O4^ii—Ba1—O4^iv	82.09 (17)	C6—O8—Ba1^viii	93.5 (6)
O1—Ba1—O4^iv	132.5 (2)	Ni1—O9—H9A	100.4
O6^iii—Ba1—O4^iv	96.5 (2)	Ni1—O9—H9B	118.7
O5—Ba1—O4^iv	156.2 (2)	H9A—O9—H9B	116.8
O11—Ba1—O7^v	71.8 (2)	Ni1—O10—H10A	102.2
O11^i—Ba1—O7^v	141.8 (2)	Ni1—O10—H10B	104.9
O4^ii—Ba1—O7^v	90.8 (2)	H10A—O10—H10B	117.2
O1—Ba1—O7^v	77.9 (2)	Ba1—O11—Ba1^iii	105.4 (2)
O6^iii—Ba1—O7^v	137.2 (2)	Ba1—O11—H11A	105.6
O5—Ba1—O7^v	124.2 (2)	Ba1^iii—O11—H11A	82.5
O4^iv—Ba1—O7^v	79.4 (2)	Ba1—O11—H11B	106.0
O11—Ba1—O8^v	108.6 (2)	Ba1^iii—O11—H11B	136.7
O11^i—Ba1—O8^v	137.9 (2)	H11A—O11—H11B	116.3
O4^ii—Ba1—O8^v	75.8 (2)	O2—C1—O1	124.2 (10)
O1—Ba1—O8^v	68.5 (2)	O2—C1—C2	118.0 (10)
O6^iii—Ba1—O8^v	140.5 (2)	O1—C1—C2	117.7 (10)
O5—Ba1—O8^v	83.3 (2)	C3—C2—C1	113.8 (9)
O4^iv—Ba1—O8^v	117.8 (2)	C3—C2—H2A	108.8
O7^v—Ba1—O8^v	44.3 (2)	C1—C2—H2A	108.8
O11—Ba1—C6^v	87.9 (2)	C3—C2—H2B	108.8
O11^i—Ba1—C6^v	149.8 (3)	C1—C2—H2B	108.8
O4^ii—Ba1—C6^v	86.8 (2)	H2A—C2—H2B	107.7
O1—Ba1—C6^v	67.8 (2)	O3—C3—O4	121.1 (11)
O6^iii—Ba1—C6^v	140.2 (2)	O3—C3—C2	117.8 (9)
O5—Ba1—C6^v	102.4 (2)	O4—C3—C2	121.1 (11)
O4^iv—Ba1—C6^v	100.7 (2)	O6—C4—O5	124.4 (10)
O7^v—Ba1—C6^v	22.5 (2)	O6—C4—C5	115.3 (9)
O8^v—Ba1—C6^v	22.6 (2)	O5—C4—C5	120.2 (9)
O3—Ni1—O5	172.2 (3)	C6—C5—C4	118.9 (10)
O3—Ni1—O1	89.4 (3)	C6—C5—H5A	107.6
O5—Ni1—O1	92.2 (3)	C4—C5—H5A	107.6
O3—Ni1—O7	88.7 (3)	C6—C5—H5B	107.6
O5—Ni1—O7	90.1 (3)	C4—C5—H5B	107.6
O1—Ni1—O7	176.4 (3)	H5A—C5—H5B	107.0
O3—Ni1—O9	96.1 (3)	O7—C6—O8	123.1 (10)
O5—Ni1—O9	91.6 (3)	O7—C6—C5	119.3 (10)
O1—Ni1—O9	87.6 (3)	O8—C6—C5	117.5 (10)
O7—Ni1—O9	89.5 (3)	O7—C6—Ba1^viii	62.6 (5)
O3—Ni1—O10	87.6 (3)	O8—C6—Ba1^viii	63.9 (5)
O5—Ni1—O10	84.9 (3)	C5—C6—Ba1^viii	157.9 (7)

Symmetry codes: (i) x, −y+1, z−1/2; (ii) x+1/2, −y+3/2, z−1/2; (iii) x, −y+1, z+1/2; (iv) x+1/2, y−1/2, z; (v) x+1/2, −y+3/2, z+1/2; (vi) x−1/2, −y+3/2, z+1/2; (vii) x−1/2, y+1/2, z; (viii) x−1/2, −y+3/2, z−1/2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O9—H9A···O2^ix	0.85	1.85	2.672 (11)	163
O11—H11A···O3^v	0.85	1.79	2.622 (11)	166
O11—H11B···O2	0.85	1.85	2.677 (10)	162
O9—H9B···O8^v	0.85	2.12	2.903 (10)	153
O10—H10A···O8^x	0.85	2.07	2.886 (10)	160
O10—H10B···O6^iii	0.85	1.92	2.772 (10)	176

Symmetry codes: (iii) x, −y+1, z+1/2; (v) x+1/2, −y+3/2, z+1/2; (ix) x, y, z−1; (x) x, y, z+1.