Bis(μ-pyridazine-3-carboxyl­ato-κ2O:O′)bis­[aqua­dioxido(pyridazine-3-carboxyl­ato-κ2N2,O)uranium(VI)] dihydrate

Leciejewicz, J.; Starosta, W.

doi:10.1107/S1600536808042219

metal-organic compounds

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ISSN: 2056-9890

Volume 65| Part 1| January 2009| Page m94

doi:10.1107/S1600536808042219

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Bis(μ-pyridazine-3-carboxylato-κ²O:O′)bis[aquadioxido(pyridazine-3-carboxylato-κ²N²,O)uranium(VI)] dihydrate

Janusz Leciejewicz ^a ^* and Wojciech Starosta ^a

^aInstitute of Nuclear Chemistry and Technology, ul. Dorodna 16, 03-195 Warszawa, Poland
^*Correspondence e-mail: jlec@ichtj.waw.pl

(Received 6 November 2008; accepted 11 December 2008; online 17 December 2008)

The structure of the binuclear title complex, [U₂(C₅H₃N₂O₂)₄O₄(H₂O)₂]·2H₂O, is composed of centrosymmetric dimers in which each UO₂²⁺ ion is coordinated by two ligand molecules. One donates its N,O-bonding group and the other donates both carboxylate O atoms. Each of the latter bridges adjacent uranyl ions. The coordination environment of the metal center is a distorted pentagonal bipyramid. The dimers are interconnected by O—H⋯O hydrogen bonds between coordinated and uncoordinated water molecules and carboxylate O atoms. An intramolecular O—H⋯N interaction is also present.

Related literature

For the crystal structure of pyridazine–3–carboxylic acid hydrochloride, see: Gryz et al. (2003 ). For centrosymmetric dimeric molecules with a different bridging mode for the title ligand to calcium(II), see: Starosta & Leciejewicz (2007 ). For bond distances and angles in uranyl complexes with carboxylate ligands, see: Leciejewicz et al. (1995 ).

Experimental

Crystal data

[U₂(C₅H₃N₂O₂)₄O₄(H₂O)₂]·2H₂O
M_r = 1104.50
Monoclinic, C 2/c
a = 25.660 (5) Å
b = 6.8330 (14) Å
c = 16.673 (3) Å
β = 96.73 (3)°
V = 2903.2 (10) Å³
Z = 4
Mo Kα radiation
μ = 11.23 mm⁻¹
T = 293 (2) K
0.19 × 0.12 × 0.07 mm

Data collection

Kuma KM-4 four-circle diffractometer
Absorption correction: analytical (CrysAlis RED; Oxford Diffraction, 2008 $[Oxford Diffraction (2008). CrysAlis RED. Oxford Diffraction Ltd., Abingdon, England.]$ ) T_min = 0.234, T_max = 0.470
4406 measured reflections
4266 independent reflections
2746 reflections with I > 2σ(I)
R_int = 0.025
3 standard reflections every 200 reflections intensity decay: 1.0%

Refinement

R[F² > 2σ(F²)] = 0.043
wR(F²) = 0.127
S = 1.01
4266 reflections
220 parameters
5 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 2.83 e Å⁻³
Δρ_min = −4.65 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O4—H42⋯O22ⁱ	0.81 (11)	2.23 (9)	2.933 (9)	146 (14)
O4—H41⋯O22	0.83 (8)	1.98 (8)	2.803 (10)	175 (13)
O3—H31⋯N11	0.82 (9)	1.94 (9)	2.754 (9)	170 (13)
O3—H32⋯O4ⁱⁱ	0.82 (6)	1.90 (9)	2.707 (12)	170 (13)
Symmetry codes: (i) $[-x+{\script{1\over 2}}, -y+{\script{3\over 2}}, -z+1]$ ; (ii) $[x, -y+1, z-{\script{1\over 2}}]$ .

Data collection: KM-4 Software (Kuma, 1996 $[Kuma (1996). KM-4 Software. Kuma Diffraction Ltd. Wrocław, Poland.]$ ); cell refinement: KM-4 Software; data reduction: DATAPROC (Kuma, 2001 $[Kuma (2001). DATAPROC. Kuma Diffraction Ltd. Wrocław, Poland.]$ ); 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.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808042219/rk2117sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808042219/rk2117Isup2.hkl

checkCIF report

Comment top

The structure of the title compound is built of centrosymmetric dimeric molecules (Fig. 1) in which each UO₂²⁺ ion is coordinated by two ligand molecules: one chelates through its N,O–bonding group, the other donates only carboxylate O atoms which bridge two adjacent uranyl ions. The U ions, ligand molecules and coordinated water O atoms form a plane [r.m.s 0.1063 (2) Å]. The coordination around the uranyl ion is pentagonal bipyramidal. The equatorial plane of the pyramid [r.m.s 0.0674 (2) Å] consists of a water O3 atom, a hetro–cycle N21 atom, a carboxylate O21 atom donated by one ligand molecule, and two bridging O11 and O12 atoms, each donated by the other ligand molecules. Maximum shifts from the mean plane show the N21 [+0.1228 (2) Å] and the carboxylate O21 [-0.1056 (2) Å] atoms. The mean U—O bond distance in the UO₂²⁺ ion is 1.755 (8) Å], the O1—U—O2 angle is 178.2 (3)°. The U—O bond distances and bond angles within the equatorial plane fall in the range commonly observed in uranyl complexes with carboxylate ligands (Leciejewicz et al., 1995). Bond lengths and bond angles within the ligand molecules agree well with those reported in the structure of the title ligand (Gryz et al., 2003). The dimers interact by H bonds and form molecular sheet in which coordinated and solvent water molecules are the donors and carboxylate O atoms - the acceptors (Fig. 2). An intra–dimer H bond of 2.754 (9) Å is also observed.

Related literature top

For the crystal structure of pyridazine–3–carboxylic acid hydrochloride, see: Gryz et al. (2003). For centrosymmetric dimeric molecules with a different bridging mode for the title ligand to calcium(II), see: Starosta & Leciejewicz (2007). For bond distances and angles in uranyl complexes with carboxylate ligands, see: Leciejewicz et al. (1995).

Experimental top

Hot aqueous solutions containing 2 mmol of pyridazine–3–carboxylic acid and 1 mmol of uranyl nitrate hexahydrate, respectively, were mixed and boiled for two hours with constant stirring and left to crystallize at room temperature. After few days, well formed green single crystals were found in the mother liquor. They were washed with cold ethanol and dried in air.

Computing details top

Data collection: KM-4 Software (Kuma, 1996); cell refinement: KM-4 Software (Kuma, 1996); data reduction: DATAPROC (Kuma, 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

	Fig. 1. View a dimer of title compound with the atom labelling scheme. Displacement ellipsoids are drawn at 50% probability level. H atoms are presented as a small spheres of arbitrary radius. Symmetry code: (i)-x+1, y, -z+1/2.
	Fig. 2. Packing diagram of the crystal structure.

Bis(µ-pyridazine-3-carboxylato-κ²O:O')bis[aquadioxido(pyridazine-3- carboxylato-κ²N²,O)uranium(VI)] dihydrate top

Crystal data top

[U₂(C₅H₃N₂O₂)₄O₄(H₂O)₂]·2H₂O	F(000) = 2032
M_r = 1104.50	D_x = 2.527 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 25 reflections
a = 25.660 (5) Å	θ = 6–15°
b = 6.8330 (14) Å	µ = 11.23 mm⁻¹
c = 16.673 (3) Å	T = 293 K
β = 96.73 (3)°	Block, light green
V = 2903.2 (10) Å³	0.19 × 0.12 × 0.07 mm
Z = 4

Data collection top

Kuma KM-4 four-circle diffractometer	2746 reflections with I > 2σ(I)
Radiation source: Fine–focus sealed tube	R_int = 0.025
Graphite monochromator	θ_max = 30.1°, θ_min = 1.6°
ω/2θ profile scans	h = −36→35
Absorption correction: analytical (CrysAlis RED; Oxford Diffraction, 2008)	k = −9→0
T_min = 0.234, T_max = 0.470	l = 0→23
4406 measured reflections	3 standard reflections every 200 reflections
4266 independent reflections	intensity decay: 1.0%

Refinement top

Refinement on F²	Primary atom site location: Direct
Least-squares matrix: Full	Secondary atom site location: Difmap
R[F² > 2σ(F²)] = 0.043	Hydrogen site location: Geom
wR(F²) = 0.127	H atoms treated by a mixture of independent and constrained refinement
S = 1.01	w = 1/[σ²(F_o²) + (0.0893P)²], where P = (F_o² + 2F_c²)/3
4266 reflections	(Δ/σ)_max < 0.001
220 parameters	Δρ_max = 2.83 e Å⁻³
5 restraints	Δρ_min = −4.65 e Å⁻³

Crystal data top

[U₂(C₅H₃N₂O₂)₄O₄(H₂O)₂]·2H₂O	V = 2903.2 (10) Å³
M_r = 1104.50	Z = 4
Monoclinic, C2/c	Mo Kα radiation
a = 25.660 (5) Å	µ = 11.23 mm⁻¹
b = 6.8330 (14) Å	T = 293 K
c = 16.673 (3) Å	0.19 × 0.12 × 0.07 mm
β = 96.73 (3)°

Data collection top

Kuma KM-4 four-circle diffractometer	2746 reflections with I > 2σ(I)
Absorption correction: analytical (CrysAlis RED; Oxford Diffraction, 2008)	R_int = 0.025
T_min = 0.234, T_max = 0.470	3 standard reflections every 200 reflections
4406 measured reflections	intensity decay: 1.0%
4266 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.043	5 restraints
wR(F²) = 0.127	H atoms treated by a mixture of independent and constrained refinement
S = 1.01	Δρ_max = 2.83 e Å⁻³
4266 reflections	Δρ_min = −4.65 e Å⁻³
220 parameters

Special details top

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

	x	y	z	U_iso*/U_eq
U1	0.388813 (9)	0.70410 (6)	0.214716 (15)	0.02772 (11)
O11	0.4687 (2)	0.7142 (12)	0.1613 (4)	0.0436 (16)
O21	0.3379 (2)	0.7086 (11)	0.3224 (3)	0.0425 (16)
C14	0.5457 (4)	0.7835 (16)	−0.0802 (6)	0.044 (2)
H14	0.5740	0.8037	−0.1092	0.052*
C16	0.5070 (3)	0.7471 (11)	0.0398 (5)	0.0267 (16)
O12	0.5529 (2)	0.7589 (12)	0.1677 (4)	0.0483 (19)
N21	0.2881 (3)	0.6906 (12)	0.1781 (4)	0.0365 (17)
N11	0.4595 (3)	0.7245 (12)	−0.0016 (4)	0.0345 (15)
C26	0.2583 (3)	0.6998 (13)	0.2373 (5)	0.0289 (15)
N12	0.4535 (3)	0.7342 (14)	−0.0813 (4)	0.0423 (19)
O1	0.3944 (2)	0.4495 (11)	0.2272 (4)	0.0420 (15)
C15	0.5519 (3)	0.7755 (15)	0.0024 (5)	0.0380 (19)
H15	0.5847	0.7884	0.0321	0.046*
C17	0.5096 (3)	0.7400 (12)	0.1300 (5)	0.0274 (16)
C13	0.4960 (5)	0.7605 (15)	−0.1178 (5)	0.046 (2)
H13	0.4916	0.7636	−0.1739	0.056*
O3	0.3712 (2)	0.6478 (13)	0.0725 (4)	0.0480 (19)
H32	0.361 (5)	0.537 (8)	0.060 (8)	0.072*
H31	0.398 (3)	0.655 (19)	0.050 (7)	0.072*
O22	0.2641 (2)	0.7074 (12)	0.3803 (4)	0.0478 (17)
O2	0.3827 (3)	0.9573 (12)	0.1990 (4)	0.0501 (17)
N22	0.2650 (3)	0.6893 (14)	0.0999 (4)	0.046 (2)
C27	0.2882 (3)	0.7068 (14)	0.3202 (5)	0.0313 (15)
C25	0.2035 (3)	0.7050 (14)	0.2253 (6)	0.0371 (18)
H25	0.1833	0.7094	0.2681	0.045*
C23	0.2131 (4)	0.6890 (16)	0.0858 (6)	0.045 (2)
H23	0.1976	0.6786	0.0327	0.054*
C24	0.1812 (3)	0.7034 (18)	0.1457 (7)	0.051 (3)
H24	0.1450	0.7118	0.1331	0.061*
O4	0.3251 (3)	0.6999 (15)	0.5313 (5)	0.058 (2)
H42	0.311 (5)	0.75 (2)	0.567 (5)	0.086*
H41	0.306 (5)	0.71 (2)	0.488 (4)	0.086*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
U1	0.01643 (13)	0.04731 (19)	0.02056 (14)	0.00034 (12)	0.00697 (8)	0.00059 (13)
O11	0.022 (3)	0.087 (5)	0.023 (3)	−0.010 (3)	0.007 (2)	−0.006 (3)
O21	0.027 (3)	0.082 (5)	0.020 (2)	−0.001 (3)	0.010 (2)	0.001 (3)
C14	0.048 (5)	0.054 (5)	0.033 (4)	−0.009 (4)	0.025 (4)	−0.002 (4)
C16	0.024 (3)	0.033 (5)	0.025 (3)	0.001 (2)	0.007 (3)	−0.003 (3)
O12	0.022 (3)	0.100 (6)	0.024 (3)	0.000 (3)	0.002 (2)	0.012 (3)
N21	0.021 (3)	0.065 (5)	0.025 (3)	0.001 (3)	0.008 (2)	0.003 (3)
N11	0.029 (3)	0.054 (5)	0.021 (3)	−0.002 (3)	0.005 (2)	0.002 (3)
C26	0.019 (3)	0.040 (4)	0.029 (3)	0.004 (3)	0.008 (2)	0.004 (3)
N12	0.045 (4)	0.060 (6)	0.021 (3)	−0.003 (4)	0.002 (3)	−0.003 (3)
O1	0.039 (3)	0.049 (4)	0.040 (3)	0.003 (3)	0.014 (3)	0.006 (3)
C15	0.026 (4)	0.060 (6)	0.030 (4)	−0.002 (4)	0.013 (3)	0.005 (4)
C17	0.023 (3)	0.038 (5)	0.023 (3)	0.005 (3)	0.009 (3)	0.005 (3)
C13	0.064 (6)	0.056 (7)	0.021 (4)	−0.007 (5)	0.010 (4)	0.000 (4)
O3	0.021 (3)	0.094 (6)	0.030 (3)	−0.003 (3)	0.009 (2)	0.000 (3)
O22	0.030 (3)	0.088 (5)	0.027 (3)	0.010 (3)	0.015 (2)	0.002 (3)
O2	0.057 (4)	0.047 (4)	0.048 (4)	−0.003 (3)	0.014 (3)	0.006 (3)
N22	0.027 (3)	0.088 (7)	0.024 (3)	0.001 (3)	0.003 (3)	0.005 (4)
C27	0.022 (3)	0.041 (4)	0.033 (4)	0.007 (3)	0.011 (3)	0.006 (4)
C25	0.021 (3)	0.046 (5)	0.046 (5)	−0.003 (3)	0.013 (3)	0.004 (4)
C23	0.032 (4)	0.069 (7)	0.034 (4)	0.000 (4)	−0.004 (3)	0.010 (4)
C24	0.014 (3)	0.074 (7)	0.064 (7)	0.000 (4)	−0.003 (3)	0.010 (6)
O4	0.041 (4)	0.100 (7)	0.033 (3)	0.012 (4)	0.010 (3)	0.008 (4)

Geometric parameters (Å, º) top

U1—O2	1.754 (8)	N21—N22	1.367 (10)
U1—O1	1.756 (8)	N11—N12	1.321 (10)
U1—O11	2.331 (6)	C26—C25	1.399 (10)
U1—O21	2.342 (5)	C26—C27	1.501 (11)
U1—O12ⁱ	2.352 (6)	N12—C13	1.322 (13)
U1—O3	2.393 (6)	C15—H15	0.9300
U1—N21	2.588 (7)	C13—H13	0.9300
O11—C17	1.236 (9)	O3—H32	0.82 (6)
O21—C27	1.272 (9)	O3—H31	0.82 (9)
C14—C13	1.362 (15)	O22—C27	1.237 (9)
C14—C15	1.369 (12)	N22—C23	1.326 (11)
C14—H14	0.9300	C25—C24	1.382 (15)
C16—N11	1.338 (10)	C25—H25	0.9300
C16—C15	1.385 (10)	C23—C24	1.368 (15)
C16—C17	1.500 (11)	C23—H23	0.9300
O12—C17	1.218 (9)	C24—H24	0.9300
O12—U1ⁱ	2.352 (6)	O4—H42	0.81 (11)
N21—C26	1.317 (9)	O4—H41	0.83 (8)

O2—U1—O1	178.2 (3)	N22—N21—U1	122.2 (5)
O2—U1—O11	88.9 (3)	N12—N11—C16	120.3 (7)
O1—U1—O11	90.7 (3)	N21—C26—C25	123.8 (8)
O2—U1—O21	93.1 (3)	N21—C26—C27	114.4 (6)
O1—U1—O21	88.1 (3)	C25—C26—C27	121.8 (7)
O11—U1—O21	152.6 (2)	N11—N12—C13	117.6 (8)
O2—U1—O12ⁱ	90.3 (3)	C14—C15—C16	117.0 (8)
O1—U1—O12ⁱ	91.4 (3)	C14—C15—H15	121.5
O11—U1—O12ⁱ	79.1 (2)	C16—C15—H15	121.5
O21—U1—O12ⁱ	73.5 (2)	O12—C17—O11	124.4 (7)
O2—U1—O3	90.4 (3)	O12—C17—C16	116.3 (7)
O1—U1—O3	87.8 (3)	O11—C17—C16	119.2 (7)
O11—U1—O3	72.4 (2)	N12—C13—C14	125.6 (8)
O21—U1—O3	134.8 (2)	N12—C13—H13	117.2
O12ⁱ—U1—O3	151.5 (2)	C14—C13—H13	117.2
O2—U1—N21	86.0 (3)	U1—O3—H32	115 (9)
O1—U1—N21	93.3 (3)	U1—O3—H31	112 (9)
O11—U1—N21	144.2 (2)	H32—O3—H31	101 (10)
O21—U1—N21	63.2 (2)	C23—N22—N21	118.8 (7)
O12ⁱ—U1—N21	136.3 (2)	O22—C27—O21	124.7 (8)
O3—U1—N21	72.1 (2)	O22—C27—C26	119.8 (7)
C17—O11—U1	173.0 (7)	O21—C27—C26	115.4 (6)
C27—O21—U1	128.7 (5)	C24—C25—C26	115.6 (8)
C13—C14—C15	116.8 (8)	C24—C25—H25	122.2
C13—C14—H14	121.6	C26—C25—H25	122.2
C15—C14—H14	121.6	N22—C23—C24	123.1 (9)
N11—C16—C15	122.6 (8)	N22—C23—H23	118.5
N11—C16—C17	116.3 (7)	C24—C23—H23	118.5
C15—C16—C17	121.0 (7)	C23—C24—C25	119.1 (8)
C17—O12—U1ⁱ	150.0 (6)	C23—C24—H24	120.4
C26—N21—N22	119.4 (7)	C25—C24—H24	120.4
C26—N21—U1	118.2 (5)	H42—O4—H41	110 (12)

Symmetry code: (i) −x+1, y, −z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O4—H42···O22ⁱⁱ	0.81 (11)	2.23 (9)	2.933 (9)	146 (14)
O4—H41···O22	0.83 (8)	1.98 (8)	2.803 (10)	175 (13)
O3—H31···N11	0.82 (9)	1.94 (9)	2.754 (9)	170 (13)
O3—H32···O4ⁱⁱⁱ	0.82 (6)	1.90 (9)	2.707 (12)	170 (13)

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

Experimental details

Crystal data
Chemical formula	[U₂(C₅H₃N₂O₂)₄O₄(H₂O)₂]·2H₂O
M_r	1104.50
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	293
a, b, c (Å)	25.660 (5), 6.8330 (14), 16.673 (3)
β (°)	96.73 (3)
V (Å³)	2903.2 (10)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	11.23
Crystal size (mm)	0.19 × 0.12 × 0.07

Data collection
Diffractometer	Kuma KM-4 four-circle diffractometer
Absorption correction	Analytical (CrysAlis RED; Oxford Diffraction, 2008)
T_min, T_max	0.234, 0.470
No. of measured, independent and observed [I > 2σ(I)] reflections	4406, 4266, 2746
R_int	0.025
(sin θ/λ)_max (Å⁻¹)	0.705

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.043, 0.127, 1.01
No. of reflections	4266
No. of parameters	220
No. of restraints	5
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	2.83, −4.65

Computer programs: KM-4 Software (Kuma, 1996), DATAPROC (Kuma, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O4—H42···O22ⁱ	0.81 (11)	2.23 (9)	2.933 (9)	146 (14)
O4—H41···O22	0.83 (8)	1.98 (8)	2.803 (10)	175 (13)
O3—H31···N11	0.82 (9)	1.94 (9)	2.754 (9)	170 (13)
O3—H32···O4ⁱⁱ	0.82 (6)	1.90 (9)	2.707 (12)	170 (13)

Symmetry codes: (i) −x+1/2, −y+3/2, −z+1; (ii) x, −y+1, z−1/2.

References

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