Bis{2-[(1H-pyrrol-2-yl)methyl­imino­meth­yl]phenolato-κ2N,O}zinc(II)

Cui, Y.-M.; Zhang, X.; Liu, L.; Wang, Q.

doi:10.1107/S1600536809034217

metal-organic compounds

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ISSN: 2056-9890

Volume 65| Part 9| September 2009| Page m1151

doi:10.1107/S1600536809034217

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Bis{2-[(1H-pyrrol-2-yl)methyliminomethyl]phenolato-κ²N,O}zinc(II)

Yong-Ming Cui,^a Xian Zhang,^a Lian Liu ^a and Qiang Wang ^a ^*

^aEngineering Research Center for Clean Production of Textile Dyeing and Printing, Ministry of Education, Wuhan 430073, People's Republic of China
^*Correspondence e-mail: qiangqiang_wang@163.com

(Received 19 August 2009; accepted 26 August 2009; online 29 August 2009)

In the title compound, [Zn(C₁₂H₁₁N₂O)₂], the Zn^II atom, lying on an inversion center, is coordinated by two O atoms and two N atoms from two salicylal Schiff base ligands in a distorted square-planar geometry. A three-dimensional network is formed by intermolecular C—H⋯N hydrogen bonds and C—H⋯π contacts.

Related literature

For general background to Schiff base complexes, see: Qiu et al. (2006 ); Shi et al. (2007 ); Xiao et al. (2007a ,b , 2008 ); You et al. (2006 ). For related structures, see: Qiu et al. (2004 ); You et al. (2004 ).

Experimental

Crystal data

[Zn(C₁₂H₁₁N₂O)₂]
M_r = 463.83
Triclinic, $[P \overline 1]$
a = 5.3443 (4) Å
b = 9.8669 (8) Å
c = 10.1392 (8) Å
α = 104.108 (1)°
β = 95.830 (1)°
γ = 100.126 (1)°
V = 504.58 (7) Å³
Z = 1
Mo Kα radiation
μ = 1.25 mm⁻¹
T = 200 K
0.30 × 0.30 × 0.20 mm

Data collection

Bruker SMART APEX CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.706, T_max = 0.789
6063 measured reflections
2455 independent reflections
2432 reflections with I > 2σ(I)
R_int = 0.047

Refinement

R[F² > 2σ(F²)] = 0.050
wR(F²) = 0.144
S = 1.11
2455 reflections
142 parameters
H-atom parameters constrained
Δρ_max = 1.07 e Å⁻³
Δρ_min = −0.73 e Å⁻³

Table 1
Selected bond lengths (Å)

Zn1—O1	1.8967 (19)
Zn1—N1	2.001 (2)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C8—H8A⋯O1ⁱ	0.99	2.26	2.770 (3)	111
C7—H7⋯N2ⁱⁱ	0.95	2.51	3.453 (3)	170
C6—H6⋯Cg1ⁱⁱⁱ	0.95	2.73	3.624 (3)	158
C11—H11⋯Cg2^iv	0.95	2.81	3.615 (3)	143
Symmetry codes: (i) -x+1, -y+2, -z+1; (ii) -x+1, -y+1, -z+1; (iii) -x+2, -y+2, -z+1; (iv) x, y, z+1. Cg1 and Cg2 are the centroids of the N2,C9–C12 and C1–C6 rings, respectively.

Data collection: SMART (Bruker, 2007 ); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; 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 global, I. DOI: 10.1107/S1600536809034217/hy2222sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809034217/hy2222Isup2.hkl

checkCIF report

Comment top

In preparing metal complexes, Schiff base ligands have been frequently employed (Qiu et al., 2004, 2006; Shi et al., 2007; Xiao et al., 2007a,b; Xiao et al., 2008; You et al., 2006). Zinc derivatives are particularly interesting owing to their essential importance in several biological processes (You et al., 2004, 2006; Xiao et al., 2007a,b; Xiao et al., 2008). We have reported the structures of a few zinc(II) complexes (You et al., 2004; Qiu et al., 2004). As an extension of our work, we report here the structure of a zinc(II) complex with salicylal Schiff base ligands.

The title compound consists of a Zn^II atom, lying on an inversion center, and two bidentate salicylal Schiff base ligands. The central Zn^II atom is coordinated by two N atoms from the pyrrole groups and two O atoms from the phenolate groups, forming a slightly distorted square-planar geometry (Fig. 1). The distortion arises from the difference between Zn—O and Zn—N bonds (Table 1). The six-membered ring (Zn1, N1, C7, C2, C1, O1) and the benzene ring are almost co-planar with a mean deviation of 0.046 (1) Å.

Intramolecular C—H···O hydrogen bond occours between H8A and O1 (Fig. 1 and Table 2). C—H···π contacts involving C6—H6···Cg1ⁱⁱⁱ [Cg1 is the centroid of N2, C9–C12 ring; symmetry code: (iii) 2-x, 2-y, 1-z] and C11—H11···Cg2^iv [Cg2 is the centroid of C1–C6 ring; (iv) x, y, 1+z] are observed (Fig. 3). These interactions as well as intermolecular C—H···N hydrogen bond (Fig. 2) connect the molecules into a three-dimensional network.

Related literature top

For general background to Schiff base complexes, see: Qiu et al. (2006); Shi et al. (2007); Xiao et al. (2007a,b, 2008); You et al. (2006). For related structures, see: Qiu et al. (2004); You et al. (2004). Cg1 and Cg2 are the centroids of the N2,C9–C12 and C1–C6 rings, respectively.

Experimental top

Zinc oxide (0.5 mmol), salicylaldehyde (1 mmol) and (1H-pyrrol-yl)methanamine (1 mmol) were dissolved in 10 ml of methanol. After 3 ml ammonia was added, the resulting solution was heated to 423 K for 10 h. The reactor was cooled to room temperature at a rate of 10 K h^-1. The mixture was filtered and held at room temperature for 10 d. Colorless block crystals were isolated (yield 38%).

Computing details top

Data collection: SMART (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); 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. Molecular structure of the title compound. Displacement ellipsoids are drawn at the 30% probability level. Dashed lines indicate hydrogen bonds. [Symmetry code: (i) 1-x, 2-y, 1-z.]
	Fig. 2. Packing diagram of the title compound. Dashed lines indicate C—H···N hydrogen bonds.
	Fig. 3. C—H···π interactions in the title compound (dashed lines).

Bis{2-[(1H-pyrrol-2-yl)methyliminomethyl]phenolato- κ²N,O}zinc(II) top

Crystal data top

[Zn(C₁₂H₁₁N₂O)₂]	Z = 1
M_r = 463.83	F(000) = 240
Triclinic, P1	D_x = 1.526 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 5.3443 (4) Å	Cell parameters from 2361 reflections
b = 9.8669 (8) Å	θ = 2.7–26.6°
c = 10.1392 (8) Å	µ = 1.25 mm⁻¹
α = 104.108 (1)°	T = 200 K
β = 95.830 (1)°	Block, colorless
γ = 100.126 (1)°	0.30 × 0.30 × 0.20 mm
V = 504.58 (7) Å³

Data collection top

Bruker SMART APEX CCD diffractometer	2455 independent reflections
Radiation source: fine-focus sealed tube	2432 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.047
ϕ and ω scans	θ_max = 28.3°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −7→7
T_min = 0.706, T_max = 0.789	k = −13→13
6063 measured reflections	l = −13→13

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.050	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.144	H-atom parameters constrained
S = 1.11	w = 1/[σ²(F_o²) + (0.0948P)² + 0.2435P] where P = (F_o² + 2F_c²)/3
2455 reflections	(Δ/σ)_max < 0.001
142 parameters	Δρ_max = 1.07 e Å⁻³
0 restraints	Δρ_min = −0.73 e Å⁻³

Crystal data top

[Zn(C₁₂H₁₁N₂O)₂]	γ = 100.126 (1)°
M_r = 463.83	V = 504.58 (7) Å³
Triclinic, P1	Z = 1
a = 5.3443 (4) Å	Mo Kα radiation
b = 9.8669 (8) Å	µ = 1.25 mm⁻¹
c = 10.1392 (8) Å	T = 200 K
α = 104.108 (1)°	0.30 × 0.30 × 0.20 mm
β = 95.830 (1)°

Data collection top

Bruker SMART APEX CCD diffractometer	2455 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	2432 reflections with I > 2σ(I)
T_min = 0.706, T_max = 0.789	R_int = 0.047
6063 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.050	0 restraints
wR(F²) = 0.144	H-atom parameters constrained
S = 1.11	Δρ_max = 1.07 e Å⁻³
2455 reflections	Δρ_min = −0.73 e Å⁻³
142 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
C1	0.8616 (5)	0.9132 (3)	0.3153 (2)	0.0297 (5)
C2	0.7761 (5)	0.7658 (3)	0.3046 (2)	0.0306 (5)
C3	0.8882 (6)	0.6636 (3)	0.2175 (3)	0.0379 (6)
H3	0.8295	0.5648	0.2088	0.045*
C4	1.0792 (6)	0.7055 (3)	0.1461 (3)	0.0392 (6)
H4	1.1518	0.6367	0.0880	0.047*
C5	1.1647 (6)	0.8508 (4)	0.1602 (3)	0.0403 (6)
H5	1.2984	0.8804	0.1120	0.048*
C6	1.0611 (5)	0.9518 (3)	0.2417 (3)	0.0363 (5)
H6	1.1246	1.0500	0.2491	0.044*
C7	0.5899 (5)	0.7143 (3)	0.3816 (3)	0.0320 (5)
H7	0.5492	0.6139	0.3688	0.038*
C8	0.2983 (5)	0.7075 (3)	0.5401 (3)	0.0331 (5)
H8A	0.1403	0.7464	0.5483	0.040*
H8B	0.2478	0.6061	0.4866	0.040*
C9	0.4297 (5)	0.7175 (3)	0.6791 (3)	0.0290 (5)
C10	0.3985 (5)	0.7807 (4)	0.8078 (3)	0.0398 (6)
H10	0.2724	0.8349	0.8336	0.048*
C11	0.5913 (6)	0.7507 (4)	0.8987 (3)	0.0447 (7)
H11	0.6185	0.7811	0.9964	0.054*
C12	0.7259 (6)	0.6713 (3)	0.8190 (3)	0.0405 (6)
H12	0.8665	0.6354	0.8519	0.049*
N1	0.4708 (4)	0.7890 (2)	0.4666 (2)	0.0297 (4)
N2	0.6319 (4)	0.6496 (2)	0.6837 (2)	0.0291 (4)
H2A	0.6901	0.6011	0.6127	0.035*
O1	0.7656 (4)	1.0126 (2)	0.3902 (2)	0.0346 (4)
Zn1	0.5000	1.0000	0.5000	0.02730 (17)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0298 (11)	0.0310 (11)	0.0267 (10)	0.0055 (9)	−0.0013 (8)	0.0079 (9)
C2	0.0311 (11)	0.0325 (12)	0.0263 (10)	0.0053 (9)	−0.0014 (8)	0.0075 (9)
C3	0.0413 (14)	0.0378 (13)	0.0334 (12)	0.0112 (11)	0.0002 (10)	0.0074 (10)
C4	0.0384 (14)	0.0478 (15)	0.0307 (12)	0.0177 (11)	0.0042 (10)	0.0035 (11)
C5	0.0349 (13)	0.0527 (17)	0.0340 (13)	0.0124 (11)	0.0044 (10)	0.0110 (12)
C6	0.0331 (12)	0.0405 (13)	0.0353 (12)	0.0057 (10)	0.0047 (9)	0.0118 (10)
C7	0.0370 (12)	0.0265 (11)	0.0300 (11)	0.0048 (9)	0.0000 (9)	0.0062 (9)
C8	0.0350 (12)	0.0292 (11)	0.0318 (11)	−0.0022 (9)	−0.0009 (9)	0.0108 (9)
C9	0.0282 (11)	0.0285 (11)	0.0320 (11)	0.0050 (8)	0.0041 (8)	0.0123 (9)
C10	0.0311 (12)	0.0613 (18)	0.0306 (12)	0.0152 (12)	0.0082 (9)	0.0140 (12)
C11	0.0368 (14)	0.069 (2)	0.0317 (13)	0.0110 (13)	0.0041 (10)	0.0206 (13)
C12	0.0392 (14)	0.0448 (15)	0.0402 (14)	0.0106 (11)	−0.0011 (11)	0.0182 (12)
N1	0.0334 (10)	0.0272 (9)	0.0269 (9)	0.0031 (7)	0.0000 (7)	0.0085 (7)
N2	0.0327 (10)	0.0275 (9)	0.0292 (9)	0.0129 (8)	0.0035 (7)	0.0074 (7)
O1	0.0368 (9)	0.0299 (9)	0.0384 (9)	0.0067 (7)	0.0114 (7)	0.0096 (7)
Zn1	0.0300 (2)	0.0258 (2)	0.0259 (2)	0.00531 (15)	0.00390 (14)	0.00714 (15)

Geometric parameters (Å, º) top

C1—O1	1.302 (3)	C8—N1	1.491 (3)
C1—C6	1.413 (4)	C8—H8A	0.9900
C1—C2	1.419 (4)	C8—H8B	0.9900
C2—C7	1.425 (4)	C9—C10	1.344 (4)
C2—C3	1.429 (4)	C9—N2	1.371 (3)
C3—C4	1.373 (4)	C10—C11	1.430 (4)
C3—H3	0.9500	C10—H10	0.9500
C4—C5	1.393 (5)	C11—C12	1.339 (5)
C4—H4	0.9500	C11—H11	0.9500
C5—C6	1.367 (4)	C12—N2	1.363 (3)
C5—H5	0.9500	C12—H12	0.9500
C6—H6	0.9500	N2—H2A	0.8800
C7—N1	1.287 (3)	Zn1—O1	1.8967 (19)
C7—H7	0.9500	Zn1—N1	2.001 (2)
C8—C9	1.481 (3)

O1—C1—C6	119.4 (2)	H8A—C8—H8B	108.1
O1—C1—C2	122.8 (2)	C10—C9—N2	109.4 (2)
C6—C1—C2	117.8 (3)	C10—C9—C8	134.5 (2)
C1—C2—C7	123.0 (2)	N2—C9—C8	116.1 (2)
C1—C2—C3	119.1 (2)	C9—C10—C11	106.9 (3)
C7—C2—C3	117.8 (2)	C9—C10—H10	126.6
C4—C3—C2	121.3 (3)	C11—C10—H10	126.6
C4—C3—H3	119.4	C12—C11—C10	106.5 (3)
C2—C3—H3	119.4	C12—C11—H11	126.8
C3—C4—C5	118.8 (3)	C10—C11—H11	126.8
C3—C4—H4	120.6	C11—C12—N2	110.1 (2)
C5—C4—H4	120.6	C11—C12—H12	124.9
C6—C5—C4	121.7 (3)	N2—C12—H12	124.9
C6—C5—H5	119.2	C7—N1—C8	115.6 (2)
C4—C5—H5	119.2	C7—N1—Zn1	124.25 (18)
C5—C6—C1	121.3 (3)	C8—N1—Zn1	120.09 (17)
C5—C6—H6	119.3	C12—N2—C9	107.1 (2)
C1—C6—H6	119.3	C12—N2—H2A	126.4
N1—C7—C2	127.1 (2)	C9—N2—H2A	126.4
N1—C7—H7	116.4	C1—O1—Zn1	130.68 (18)
C2—C7—H7	116.4	O1ⁱ—Zn1—O1	180.000 (1)
C9—C8—N1	110.58 (19)	O1ⁱ—Zn1—N1	88.44 (9)
C9—C8—H8A	109.5	O1—Zn1—N1	91.56 (9)
N1—C8—H8A	109.5	O1ⁱ—Zn1—N1ⁱ	91.56 (9)
C9—C8—H8B	109.5	O1—Zn1—N1ⁱ	88.44 (9)
N1—C8—H8B	109.5	N1—Zn1—N1ⁱ	180.00 (12)

O1—C1—C2—C7	−4.2 (4)	C9—C10—C11—C12	−0.1 (4)
C6—C1—C2—C7	175.2 (2)	C10—C11—C12—N2	0.3 (4)
O1—C1—C2—C3	178.6 (2)	C2—C7—N1—C8	−176.0 (2)
C6—C1—C2—C3	−2.0 (3)	C2—C7—N1—Zn1	5.3 (4)
C1—C2—C3—C4	1.1 (4)	C9—C8—N1—C7	98.0 (3)
C7—C2—C3—C4	−176.3 (2)	C9—C8—N1—Zn1	−83.2 (2)
C2—C3—C4—C5	0.4 (4)	C11—C12—N2—C9	−0.4 (3)
C3—C4—C5—C6	−0.8 (4)	C10—C9—N2—C12	0.3 (3)
C4—C5—C6—C1	−0.1 (4)	C8—C9—N2—C12	179.9 (2)
O1—C1—C6—C5	−179.0 (2)	C6—C1—O1—Zn1	179.70 (17)
C2—C1—C6—C5	1.6 (4)	C2—C1—O1—Zn1	−0.9 (4)
C1—C2—C7—N1	1.6 (4)	C1—O1—Zn1—N1	5.4 (2)
C3—C2—C7—N1	178.9 (2)	C1—O1—Zn1—N1ⁱ	−174.6 (2)
N1—C8—C9—C10	111.4 (3)	C7—N1—Zn1—O1ⁱ	172.7 (2)
N1—C8—C9—N2	−68.1 (3)	C8—N1—Zn1—O1ⁱ	−5.97 (17)
N2—C9—C10—C11	−0.1 (3)	C7—N1—Zn1—O1	−7.3 (2)
C8—C9—C10—C11	−179.6 (3)	C8—N1—Zn1—O1	174.03 (17)

Symmetry code: (i) −x+1, −y+2, −z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8A···O1ⁱ	0.99	2.26	2.770 (3)	111
C7—H7···N2ⁱⁱ	0.95	2.51	3.453 (3)	170
C6—H6···Cg1ⁱⁱⁱ	0.95	2.73	3.624 (3)	158
C11—H11···Cg2^iv	0.95	2.81	3.615 (3)	143

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

Experimental details

Crystal data
Chemical formula	[Zn(C₁₂H₁₁N₂O)₂]
M_r	463.83
Crystal system, space group	Triclinic, P1
Temperature (K)	200
a, b, c (Å)	5.3443 (4), 9.8669 (8), 10.1392 (8)
α, β, γ (°)	104.108 (1), 95.830 (1), 100.126 (1)
V (Å³)	504.58 (7)
Z	1
Radiation type	Mo Kα
µ (mm⁻¹)	1.25
Crystal size (mm)	0.30 × 0.30 × 0.20

Data collection
Diffractometer	Bruker SMART APEX CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.706, 0.789
No. of measured, independent and observed [I > 2σ(I)] reflections	6063, 2455, 2432
R_int	0.047
(sin θ/λ)_max (Å⁻¹)	0.667

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.050, 0.144, 1.11
No. of reflections	2455
No. of parameters	142
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.07, −0.73

Computer programs: SMART (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Selected bond lengths (Å) top

Zn1—O1

1.8967 (19)

Zn1—N1

2.001 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8A···O1ⁱ	0.99	2.26	2.770 (3)	111
C7—H7···N2ⁱⁱ	0.95	2.51	3.453 (3)	170
C6—H6···Cg1ⁱⁱⁱ	0.95	2.73	3.624 (3)	158
C11—H11···Cg2^iv	0.95	2.81	3.615 (3)	143

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

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ISSN: 2056-9890

Volume 65| Part 9| September 2009| Page m1151

doi:10.1107/S1600536809034217

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