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Acta Cryst. (2008). E64, m1498    [ doi:10.1107/S1600536808035174 ]

Triaqua(2,2'-bipyridine-[kappa]2N,N')(5-nitroisophthalato-[kappa]O1)zinc(II) monohydrate

L. Hao and X. Liu

Abstract top

In the title compound, [Zn(C8H3NO6)(C10H8N2)(H2O)3]·H2O, the ZnII cation is hexacoordinated by a chelating 2,2'-bipyridine ligand, one carboxylate O atom from a 5-nitroisophthalate dianion and three water molecules in a slightly distorted octahedral geometry. The structure contains isolated neutral complexes, in contrast to coordination polymers formed by MnII, CoII and CuII with the same ligand set. An extensive network of hydrogen bonds is formed between the water molecules and the carboxylate groups.

Comment top

In recent years, carboxylic acids have been widely used in materials science as polydentate ligands which can coordinate to transition-metal or rare-earth cations to yield complexes with interesting or useful properties. For example, Kim et al. (2001) have focused on the syntheses of transition-metal complexes containing benzene carboxylate and rigid aromatic pyridine ligands in order to study their electronic conductivity and magnetic properties. The importance of transition-metal dicarboxylate complexes motivated us to pursue synthetic strategies for these compounds, using 5-nitroisophthalic acid as a polydentate ligand.

Related literature top

For related coordination polymers formed with the same ligand set and MnII, CoII or CuII, see: Xiao et al. (2005); Xie et al. (2005, 2006). For other examples of transition-metal complexes containing benzene carboxylates and pyridine-based ligands, see: Kim et al. (2001).

Experimental top

A mixture of zinc dichloride (0.5 mmol), 2,2'-bipyridine (0.5 mmol), and 5-nitroisophthalic acid (0.5 mmol) in H2O (8 ml) and ethanol (8 ml) was sealed in a 25 ml Teflon-lined stainless steel autoclave and kept at 413 K for three days. Colourless crystals were obtained after cooling to room temperature with a yield of 27%. Elemental analysis calculated: C 42.97, H 3.78, N 9.55%; found: C 42.86, H 3.76, N 9.51%.

Refinement top

The H atoms of the water molecule were located from difference density maps. The O—H bonds were normalised to 0.84 Å, and the H atoms were then allowed to ride on the parent O atom with Uiso(H) = 1.5Ueq(O). All other H atoms were placed in calculated positions with a C—H bond distance of 0.93 Å and refined as riding with Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT-Plus (Bruker, 2001); data reduction: SAINT-Plus (Bruker, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound showing displacement ellipsoids at 50% probability for non-H atoms.
Triaqua(2,2'-bipyridine-κ2N,N')(5-nitroisophthalato-κO1)zinc(II) monohydrate top
Crystal data top
[Zn(C8H3NO6)(C10H8N2)(H2O)3]·H2OZ = 2
Mr = 502.73F(000) = 516
Triclinic, P1Dx = 1.683 Mg m−3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.520 (1) ÅCell parameters from 3801 reflections
b = 10.6700 (15) Åθ = 1.6–26.0°
c = 12.8300 (15) ŵ = 1.30 mm−1
α = 90.024 (10)°T = 293 K
β = 87.67 (1)°Block, colorless
γ = 74.72 (1)°0.32 × 0.28 × 0.22 mm
V = 992.2 (2) Å3
Data collection top
Bruker APEXII CCD
diffractometer		3801 independent reflections
Radiation source: fine-focus sealed tube3240 reflections with I > 2σ(I)
graphiteRint = 0.016
φ and ω scansθmax = 26.0°, θmin = 1.6°
Absorption correction: multi-scan
(SADABS; Bruker, 2001)		h = −9→9
Tmin = 0.592, Tmax = 0.747k = −13→13
5594 measured reflectionsl = 0→15
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)] = 0.051Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.147H-atom parameters constrained
S = 1.06 w = 1/[σ2(Fo2) + (0.0817P)2 + 1.7563P]
where P = (Fo2 + 2Fc2)/3
3801 reflections(Δ/σ)max < 0.001
289 parametersΔρmax = 1.13 e Å−3
0 restraintsΔρmin = −0.72 e Å−3
Crystal data top
[Zn(C8H3NO6)(C10H8N2)(H2O)3]·H2Oγ = 74.72 (1)°
Mr = 502.73V = 992.2 (2) Å3
Triclinic, P1Z = 2
a = 7.520 (1) ÅMo Kα radiation
b = 10.6700 (15) ŵ = 1.30 mm−1
c = 12.8300 (15) ÅT = 293 K
α = 90.024 (10)°0.32 × 0.28 × 0.22 mm
β = 87.67 (1)°
Data collection top
Bruker APEXII CCD
diffractometer		3801 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2001)		3240 reflections with I > 2σ(I)
Tmin = 0.592, Tmax = 0.747Rint = 0.016
5594 measured reflectionsθmax = 26.0°
Refinement top
R[F2 > 2σ(F2)] = 0.051H-atom parameters constrained
wR(F2) = 0.147Δρmax = 1.13 e Å−3
S = 1.06Δρmin = −0.72 e Å−3
3801 reflectionsAbsolute structure: ?
289 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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*/Ueq
Zn10.72904 (6)0.47118 (4)0.78573 (3)0.02670 (18)
C10.5256 (5)1.0550 (3)0.6738 (3)0.0200 (7)
C20.4383 (5)1.1472 (3)0.7462 (3)0.0204 (7)
H2A0.41661.23510.73140.024*
C30.3825 (5)1.1075 (3)0.8421 (3)0.0185 (7)
C40.2892 (5)1.2039 (3)0.9251 (3)0.0192 (7)
C50.4090 (5)0.9779 (3)0.8610 (3)0.0206 (7)
H5A0.36750.95130.92430.025*
C60.4968 (5)0.8863 (3)0.7869 (3)0.0212 (7)
C70.5604 (5)0.9247 (3)0.6925 (3)0.0230 (7)
H7A0.62480.86370.64330.028*
C80.5179 (5)0.7461 (3)0.8070 (3)0.0258 (8)
C90.7336 (6)0.5092 (4)0.5475 (3)0.0323 (9)
H9A0.66300.59320.56300.039*
C100.7887 (7)0.4771 (5)0.4446 (3)0.0434 (11)
H10A0.75300.53680.39170.052*
C110.8961 (8)0.3562 (5)0.4235 (3)0.0491 (13)
H11A0.93830.33210.35540.059*
C120.9428 (7)0.2692 (4)0.5027 (3)0.0396 (11)
H12A1.01830.18610.48900.048*
C130.8759 (5)0.3064 (3)0.6038 (3)0.0216 (7)
C140.9011 (5)0.2164 (3)0.6926 (3)0.0190 (7)
C150.9850 (5)0.0861 (4)0.6817 (3)0.0279 (8)
H15A1.04290.05160.61870.033*
C160.9811 (6)0.0076 (4)0.7667 (4)0.0355 (10)
H16A1.0358−0.08120.76110.043*
C170.8971 (6)0.0598 (4)0.8594 (3)0.0326 (9)
H17A0.89080.00710.91650.039*
C180.8232 (5)0.1903 (4)0.8660 (3)0.0267 (8)
H18A0.77000.22670.92950.032*
N10.5836 (5)1.0974 (3)0.5725 (2)0.0275 (7)
N20.7767 (4)0.4257 (3)0.6256 (2)0.0215 (6)
N30.8239 (4)0.2684 (3)0.7848 (2)0.0192 (6)
O10.6969 (4)1.0197 (3)0.5172 (2)0.0373 (7)
O20.5184 (5)1.2084 (3)0.5476 (2)0.0445 (8)
O30.2776 (4)1.3214 (2)0.9070 (2)0.0255 (6)
O40.2275 (4)1.1635 (3)1.0056 (2)0.0337 (7)
O50.3987 (5)0.7173 (3)0.8669 (3)0.0524 (10)
O60.6527 (4)0.6677 (2)0.7630 (2)0.0254 (6)
O71.0013 (4)0.4817 (3)0.7943 (2)0.0272 (6)
H1W1.00420.55490.81720.041*
H2W1.06980.42720.83250.041*
O80.4497 (4)0.4721 (2)0.7915 (2)0.0273 (6)
H3W0.39890.54510.81860.041*
H4W0.40610.41970.82640.041*
O90.7038 (4)0.4909 (3)0.9526 (2)0.0347 (7)
H5W0.71880.55860.98020.052*
H6W0.67840.43970.99700.052*
O100.0498 (5)0.6904 (4)0.8813 (5)0.113 (3)
H7W0.15790.69860.87680.169*
H8W−0.03870.73700.91750.169*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Zn10.0308 (3)0.0205 (3)0.0280 (3)−0.00584 (19)0.00216 (18)−0.00145 (17)
C10.0244 (18)0.0183 (17)0.0177 (16)−0.0059 (14)−0.0015 (14)−0.0002 (13)
C20.0244 (18)0.0132 (16)0.0245 (18)−0.0060 (13)−0.0034 (14)0.0019 (13)
C30.0185 (17)0.0152 (16)0.0220 (17)−0.0050 (13)0.0002 (13)−0.0002 (13)
C40.0197 (17)0.0125 (16)0.0241 (17)−0.0019 (13)−0.0012 (14)−0.0004 (13)
C50.0203 (17)0.0149 (16)0.0257 (18)−0.0037 (13)0.0036 (14)0.0015 (13)
C60.0199 (17)0.0101 (16)0.0322 (19)−0.0021 (13)0.0017 (14)0.0000 (14)
C70.0252 (18)0.0167 (17)0.0260 (18)−0.0039 (14)0.0017 (15)−0.0051 (14)
C80.0234 (19)0.0114 (16)0.042 (2)−0.0038 (14)0.0057 (16)−0.0009 (15)
C90.042 (2)0.025 (2)0.027 (2)−0.0042 (17)−0.0037 (17)0.0066 (16)
C100.068 (3)0.041 (3)0.023 (2)−0.016 (2)−0.006 (2)0.0102 (18)
C110.085 (4)0.046 (3)0.019 (2)−0.023 (3)0.010 (2)−0.0022 (19)
C120.060 (3)0.032 (2)0.024 (2)−0.010 (2)0.016 (2)−0.0078 (17)
C130.0265 (19)0.0175 (17)0.0211 (17)−0.0069 (14)0.0033 (14)−0.0011 (13)
C140.0215 (17)0.0160 (16)0.0197 (17)−0.0053 (13)−0.0003 (13)−0.0003 (13)
C150.031 (2)0.0176 (18)0.032 (2)−0.0019 (15)0.0039 (16)−0.0042 (15)
C160.040 (2)0.0165 (19)0.048 (3)−0.0037 (17)−0.006 (2)0.0033 (17)
C170.038 (2)0.027 (2)0.036 (2)−0.0121 (18)−0.0078 (18)0.0127 (17)
C180.035 (2)0.0255 (19)0.0212 (18)−0.0117 (16)0.0004 (15)0.0040 (15)
N10.0378 (19)0.0274 (17)0.0202 (15)−0.0138 (15)−0.0002 (14)−0.0003 (13)
N20.0273 (16)0.0189 (15)0.0186 (14)−0.0070 (12)−0.0002 (12)0.0019 (11)
N30.0244 (15)0.0128 (13)0.0200 (14)−0.0045 (11)−0.0006 (12)−0.0011 (11)
O10.0459 (18)0.0380 (17)0.0252 (14)−0.0082 (14)0.0138 (13)−0.0063 (12)
O20.075 (2)0.0262 (16)0.0294 (16)−0.0094 (15)0.0061 (15)0.0088 (12)
O30.0364 (15)0.0108 (12)0.0276 (13)−0.0042 (10)0.0049 (11)−0.0013 (10)
O40.0486 (18)0.0168 (13)0.0314 (15)−0.0041 (12)0.0177 (13)0.0001 (11)
O50.0441 (19)0.0160 (14)0.095 (3)−0.0102 (13)0.0398 (19)−0.0053 (15)
O60.0282 (14)0.0084 (11)0.0365 (15)−0.0011 (10)0.0110 (11)−0.0008 (10)
O70.0257 (14)0.0190 (13)0.0376 (15)−0.0061 (10)−0.0077 (11)0.0022 (11)
O80.0232 (13)0.0186 (13)0.0402 (15)−0.0065 (10)0.0059 (11)0.0013 (11)
O90.065 (2)0.0230 (14)0.0190 (13)−0.0171 (14)0.0029 (13)−0.0040 (10)
O100.036 (2)0.074 (3)0.229 (7)−0.025 (2)0.051 (3)−0.107 (4)
Geometric parameters (Å, °) top
Zn1—O62.047 (2)C11—C121.370 (7)
Zn1—O72.087 (3)C11—H11A0.930
Zn1—N32.092 (3)C12—C131.391 (5)
Zn1—O82.096 (3)C12—H12A0.930
Zn1—N22.105 (3)C13—N21.318 (5)
Zn1—O92.148 (3)C13—C141.475 (5)
C1—C21.368 (5)C14—N31.349 (4)
C1—C71.369 (5)C14—C151.371 (5)
C1—N11.463 (5)C15—C161.380 (6)
C2—C31.386 (5)C15—H15A0.930
C2—H2A0.930C16—C171.370 (6)
C3—C51.367 (5)C16—H16A0.930
C3—C41.497 (5)C17—C181.357 (6)
C4—O41.240 (4)C17—H17A0.930
C4—O31.255 (4)C18—N31.335 (5)
C5—C61.380 (5)C18—H18A0.930
C5—H5A0.930N1—O21.204 (5)
C6—C71.385 (5)N1—O11.222 (4)
C6—C81.486 (5)O7—H1W0.840
C7—H7A0.930O7—H2W0.840
C8—O61.245 (4)O8—H3W0.840
C8—O51.256 (5)O8—H4W0.840
C9—N21.334 (5)O9—H5W0.840
C9—C101.382 (6)O9—H6W0.840
C9—H9A0.930O10—H7W0.840
C10—C111.350 (7)O10—H8W0.840
C10—H10A0.930
O6—Zn1—O788.46 (11)C10—C11—C12119.8 (4)
O6—Zn1—N3170.99 (11)C10—C11—H11A120.1
O7—Zn1—N389.04 (11)C12—C11—H11A120.1
O6—Zn1—O889.13 (10)C11—C12—C13119.3 (4)
O7—Zn1—O8174.03 (10)C11—C12—H12A120.4
N3—Zn1—O894.16 (11)C13—C12—H12A120.4
O6—Zn1—N294.11 (11)N2—C13—C12121.2 (4)
O7—Zn1—N289.58 (11)N2—C13—C14115.1 (3)
N3—Zn1—N277.22 (11)C12—C13—C14123.6 (3)
O8—Zn1—N296.04 (11)N3—C14—C15121.4 (3)
O6—Zn1—O993.40 (11)N3—C14—C13115.7 (3)
O7—Zn1—O987.99 (12)C15—C14—C13122.8 (3)
N3—Zn1—O995.16 (11)C14—C15—C16118.2 (4)
O8—Zn1—O986.70 (12)C14—C15—H15A120.9
N2—Zn1—O9172.05 (11)C16—C15—H15A120.9
C2—C1—C7122.4 (3)C17—C16—C15120.4 (4)
C2—C1—N1118.8 (3)C17—C16—H16A119.8
C7—C1—N1118.8 (3)C15—C16—H16A119.8
C1—C2—C3119.0 (3)C18—C17—C16118.4 (4)
C1—C2—H2A120.5C18—C17—H17A120.8
C3—C2—H2A120.5C16—C17—H17A120.8
C5—C3—C2119.6 (3)N3—C18—C17122.5 (4)
C5—C3—C4119.0 (3)N3—C18—H18A118.8
C2—C3—C4121.3 (3)C17—C18—H18A118.8
O4—C4—O3124.6 (3)O2—N1—O1122.8 (3)
O4—C4—C3118.5 (3)O2—N1—C1118.3 (3)
O3—C4—C3117.0 (3)O1—N1—C1118.9 (3)
C3—C5—C6120.6 (3)C13—N2—C9118.5 (3)
C3—C5—H5A119.7C13—N2—Zn1115.1 (2)
C6—C5—H5A119.7C9—N2—Zn1126.0 (3)
C5—C6—C7120.3 (3)C18—N3—C14119.1 (3)
C5—C6—C8119.9 (3)C18—N3—Zn1126.6 (2)
C7—C6—C8119.8 (3)C14—N3—Zn1114.2 (2)
C1—C7—C6118.0 (3)C8—O6—Zn1125.6 (2)
C1—C7—H7A121.0Zn1—O7—H1W110.4
C6—C7—H7A121.0Zn1—O7—H2W116.7
O6—C8—O5125.9 (3)H1W—O7—H2W105.6
O6—C8—C6117.0 (3)Zn1—O8—H3W102.2
O5—C8—C6117.1 (3)Zn1—O8—H4W124.1
N2—C9—C10123.2 (4)H3W—O8—H4W104.6
N2—C9—H9A118.4Zn1—O9—H5W118.6
C10—C9—H9A118.4Zn1—O9—H6W129.1
C11—C10—C9117.9 (4)H5W—O9—H6W112.3
C11—C10—H10A121.1H7W—O10—H8W126.1
C9—C10—H10A121.1
C7—C1—C2—C3−0.1 (5)C2—C1—N1—O1163.3 (3)
N1—C1—C2—C3179.8 (3)C7—C1—N1—O1−16.8 (5)
C1—C2—C3—C5−2.6 (5)C12—C13—N2—C93.2 (6)
C1—C2—C3—C4179.0 (3)C14—C13—N2—C9−173.9 (3)
C5—C3—C4—O4−4.9 (5)C12—C13—N2—Zn1−169.7 (3)
C2—C3—C4—O4173.6 (3)C14—C13—N2—Zn113.2 (4)
C5—C3—C4—O3175.8 (3)C10—C9—N2—C13−0.4 (6)
C2—C3—C4—O3−5.7 (5)C10—C9—N2—Zn1171.7 (3)
C2—C3—C5—C62.4 (5)O6—Zn1—N2—C13163.0 (3)
C4—C3—C5—C6−179.1 (3)O7—Zn1—N2—C1374.6 (3)
C3—C5—C6—C70.4 (6)N3—Zn1—N2—C13−14.5 (3)
C3—C5—C6—C8−177.6 (3)O8—Zn1—N2—C13−107.4 (3)
C2—C1—C7—C62.9 (5)O6—Zn1—N2—C9−9.2 (3)
N1—C1—C7—C6−177.0 (3)O7—Zn1—N2—C9−97.7 (3)
C5—C6—C7—C1−3.0 (5)N3—Zn1—N2—C9173.2 (3)
C8—C6—C7—C1175.0 (3)O8—Zn1—N2—C980.3 (3)
C5—C6—C8—O6−152.1 (4)C17—C18—N3—C14−0.1 (6)
C7—C6—C8—O629.9 (5)C17—C18—N3—Zn1−176.3 (3)
C5—C6—C8—O527.7 (6)C15—C14—N3—C18−2.6 (5)
C7—C6—C8—O5−150.3 (4)C13—C14—N3—C18172.7 (3)
N2—C9—C10—C11−2.1 (7)C15—C14—N3—Zn1174.0 (3)
C9—C10—C11—C121.6 (8)C13—C14—N3—Zn1−10.7 (4)
C10—C11—C12—C131.0 (8)O7—Zn1—N3—C1899.8 (3)
C11—C12—C13—N2−3.6 (7)O8—Zn1—N3—C18−75.2 (3)
C11—C12—C13—C14173.2 (4)N2—Zn1—N3—C18−170.4 (3)
N2—C13—C14—N3−1.7 (5)O9—Zn1—N3—C1811.9 (3)
C12—C13—C14—N3−178.7 (4)O7—Zn1—N3—C14−76.5 (2)
N2—C13—C14—C15173.5 (3)O8—Zn1—N3—C14108.5 (2)
C12—C13—C14—C15−3.5 (6)N2—Zn1—N3—C1413.3 (2)
N3—C14—C15—C163.0 (6)O9—Zn1—N3—C14−164.4 (2)
C13—C14—C15—C16−171.9 (4)O5—C8—O6—Zn1−5.3 (6)
C14—C15—C16—C17−0.7 (6)C6—C8—O6—Zn1174.5 (2)
C15—C16—C17—C18−1.9 (6)O7—Zn1—O6—C8−135.1 (3)
C16—C17—C18—N32.4 (6)O8—Zn1—O6—C839.5 (3)
C2—C1—N1—O2−16.1 (5)N2—Zn1—O6—C8135.5 (3)
C7—C1—N1—O2163.8 (4)O9—Zn1—O6—C8−47.2 (3)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O7—H2W···O3i0.841.962.776 (4)165
O7—H1W···O10ii0.841.782.607 (4)168
O8—H3W···O50.841.942.715 (4)153
O8—H4W···O3iii0.841.892.721 (4)172
O9—H5W···O3iv0.841.942.727 (4)156
O9—H6W···O5v0.842.573.414 (4)180
O10—H8W···O4vi0.841.792.631 (4)180
O10—H7W···O50.841.872.713 (5)180
Symmetry codes: (i) x+1, y−1, z; (ii) x+1, y, z; (iii) x, y−1, z; (iv) −x+1, −y+2, −z+2; (v) −x+1, −y+1, −z+2; (vi) −x, −y+2, −z+2.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O7—H2W···O3i0.841.962.776 (4)165
O7—H1W···O10ii0.841.782.607 (4)168
O8—H3W···O50.841.942.715 (4)153
O8—H4W···O3iii0.841.892.721 (4)172
O9—H5W···O3iv0.841.942.727 (4)156
O9—H6W···O5v0.842.573.414 (4)180
O10—H8W···O4vi0.841.792.631 (4)180
O10—H7W···O50.841.872.713 (5)180
Symmetry codes: (i) x+1, y−1, z; (ii) x+1, y, z; (iii) x, y−1, z; (iv) −x+1, −y+2, −z+2; (v) −x+1, −y+1, −z+2; (vi) −x, −y+2, −z+2.
Acknowledgements top

This work is supported by the Natural Science Foundation of Shandong Province (grant No. Y2007D39).

references
References top

Bruker (2001). SADABS and SAINT-Plus. Bruker AXS Inc., Madison, Wisconsin, USA.

Bruker (2004). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.

Kim, Y., Lee, E. & Jung, D. Y. (2001). Chem. Mater. 13, 2684–2690.

Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.

Xiao, H. P., Li, X.-H. & Cheng, Y.-Q. (2005). Acta Cryst. E61, m158–m159.

Xie, G., Zeng, M.-H., Chen, S.-P. & Gao, S.-L. (2005). Acta Cryst. E61, m2273–m2275.

Xie, G., Zeng, M.-H., Chen, S.-P. & Gao, S.-L. (2006). Acta Cryst. E62, m397–m399.