Bis(acetato-κ2O,O′)(4,4′-dimethyl-2,2′-bipyridine-κ2N,N′)­zinc

Harvey, M.A.; Suarez, S.A.; Ibañez, A.; Doctorovich, F.; Baggio, R.

doi:10.1107/S1600536812042699

metal-organic compounds

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ISSN: 2056-9890

Volume 68| Part 11| November 2012| Pages m1377-m1378

doi:10.1107/S1600536812042699

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Bis(acetato-κ²O,O′)(4,4′-dimethyl-2,2′-bipyridine-κ²N,N′)zinc

Miguel A. Harvey,^a ^* Sebastian A. Suarez,^b Andres Ibañez,^c Fabio Doctorovich ^b and Ricardo Baggio ^d

^aUniversidad Nacional de la Patagonia S.J.B. and Centro Nacional Patagonico, CONICET, Bvd. Alte. Brown 3700, 9120 Puerto Madryn, Chubut, Argentina, ^bDepartamento de Química Inorgánica, Analítica y Química, Física/INQUIMAE-CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Argentina, ^cLaboratorio de Cristalografía, Difracción de Rayos-X, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile. Av. Blanco Encalada 2008, Santiago, Chile, and ^dGerencia de Investigación y Aplicaciones, Centro Atómico Constituyentes, Comisión Nacional de Energía Atómica, Buenos Aires, Argentina
^*Correspondence e-mail: unharvey@cenpat.edu.ar

(Received 10 October 2012; accepted 11 October 2012; online 20 October 2012)

The molecular structure of the title compound, [Zn(CH₃COO)₂(C₁₂H₁₂N₂)], consists of isolated molecules bisected by a twofold rotation axis which goes through the Zn^II cation and halves the organic base through the central C—C bond. The Zn^II ion is coordinated by two N atoms from one molecule of the aromatic base and four O atoms from two bidentate, symmetry-related acetate anions, which coordinate asymmetrically [Zn—O distances of 2.058 (2) and 2.362 (3) Å], while the two Zn—N bond distances are equal as imposed by symmetry [2.079 (2) Å]. The crystal structure is supported by a number of weak C—H⋯O interactions and C—H⋯π contacts, with no π–π interactions present, mainly hindered by the substituent methyl groups and the relative molecular orientation. The result is a three-dimensional structure in which each molecule is linked to eight different neighbors.

Related literature

For properties of polypyridyl compounds, see: Steed & Atwood (2009 ). For related structures, see: Barquín et al. (2010 ). For details of the vectorial bond–valence model, see Harvey et al. (2006 ).

Experimental

Crystal data

[Zn(C₂H₃O₂)₂(C₁₂H₁₂N₂)]
M_r = 367.71
Orthorhombic, F d d 2
a = 14.4779 (5) Å
b = 28.5700 (15) Å
c = 8.0854 (3) Å
V = 3344.4 (2) Å³
Z = 8
Mo Kα radiation
μ = 1.49 mm⁻¹
T = 295 K
0.3 × 0.3 × 0.2 mm

Data collection

Oxford Diffraction Gemini CCD S Ultra diffractometer
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, England.]$ ) T_min = 0.65, T_max = 0.75
3945 measured reflections
1563 independent reflections
1481 reflections with I > 2σ(I)
R_int = 0.015

Refinement

R[F² > 2σ(F²)] = 0.026
wR(F²) = 0.068
S = 1.09
1563 reflections
107 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.28 e Å⁻³
Δρ_min = −0.26 e Å⁻³
Absolute structure: Flack (1983 ), 374 Friedel pairs
Flack parameter: 0.010 (16)

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 and Cg2 are the centroids of the Zn1,O1,C7,O2 and N1,C1–C5 rings, respectively.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2⋯O1ⁱ	0.93	2.53	3.354 (4)	147
C6—H6A⋯O2ⁱⁱ	0.96	2.56	3.438 (4)	153
C4—H4⋯Cg1ⁱⁱⁱ	0.93	2.99	3.874 (4)	160
C4—H4⋯Cg1ⁱⁱ	0.93	2.96	3.766 (4)	145
C8—H8B⋯Cg2^iv	0.96	2.96	3.804 (4)	147
Symmetry codes: (i) $[x+{\script{1\over 4}}, -y+{\script{1\over 4}}, z+{\script{1\over 4}}]$ ; (ii) -x, -y, z+1; (iii) x, y, z+1; (iv) $[x-{\script{1\over 2}}, y, z-{\script{1\over 2}}]$ .

Data collection: CrysAlis PRO (Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, England.]$ ); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; 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: SHELXL97 and PLATON (Spek, 2009).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812042699/br2212sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812042699/br2212Isup2.hkl

checkCIF report

Comment top

Polypyridil compounds and some of their derivatives have shown to be fruitful ligands in supramolecular photochemistry, due to the capability of its extended π- systems to absorb light. They can act as light harvesters as much as to relax photoexcited metal centres via MLCT to the ligand-centred π*_L orbital; some interesting examples can be found in Steed & Atwood, 2009. In particular, in the case of 4,4'-dimethyl-2,2'-bipyridine (dmbp), the presence of the methyl groups in the aromatic ligand can additionally influence the structural behavior when binding to a metal centre. We present in what follows the crystal and molecular structure of the title compound, C₁₆H₁₈N₂O₄Zn, consisting of isolated Zn(dmbp)(ac)₂, molecules (ac = acetate) bisected by a twofold axis which goes through the Zn(II) cation and halves the organic base through the central C—C bond.

The Zn(II) ion is coordinated by two nitrogen atoms from one molecule of the aromatic base and four oxygen atoms from two bidentate, symmetry related acetate anions (Fig. 1). A very similar compound, with Cu(II) as its central cation has been reported in Barquín et al., 2010. Donor atoms in the title compound can not fit in any regular polyhedron, but the three chelate ligands fulfill the vector bond valence postulate of the Vectorial Bond-Valence Model (for details on the theory see Harvey et al., 2006). The three ligand vectors, as defined therein, lay in a planar trigonal geometry with a sum of angles equal to 359.6 (2)° (ideal: 360°) and a resultant vector modulus of 0.03 v.u. (Ideal: 0.00 v.u.).

Both acetate anions coordinate asymmetrically (Zn—O distances 2.058 (2) and 2.362 (3) Å), while the two Zn—N bond distances are equal (2.079 (2) Å) as imposed by symmetry.

The crystal structure is supported by a number of weak C—H···O interactions (Table 1, entries 1,2) and C—H···π contacts (Table 1, entries 3 to 5). In spite of the presence of aromatic rings there are no π-π interactions in the structure, mainly hindered by the substituent methyl groups and the relative molecular orientation.

The overall effect of these weak interactions, uniformly distributed in space, is the formation of a three-dimensional structure where each molecule is linked to eight different neighbors. Fig. 2 presents a highly simplified packing view projected down c, where only the C—H···O bonds have been drawn, for clarity, and where the complex linkage can be envisaged.

Related literature top

For properties of polypyridyl compounds, see Steed & Atwood (2009). For related structures, see: Barquín et al. (2010). For details of the vectorial bond–valence model, see Harvey et al. (2006).

Experimental top

The title compound was obtained as an unexpected byproduct in an attempt to synthesize a Zn tetrathionate complex with the aromatic base. Solid Zn acetate dihydrate, 4,4'-Dimethylbipyridine and potassium tetrathionate, 0.050 mmol of each, were added to 5 ml of dimethylformamide. On standing, colorless blocks of the title compound could be extracted for diffraction experiments.

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell refinement: CrysAlis PRO (Oxford Diffraction, 2009); data reduction: CrysAlis PRO (Oxford Diffraction, 2009); 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: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

	Fig. 1. Ellipsoid plot of (I), drawn with displacement factors at a 40% probability level. In full(empty) ellipsods and bonds, the independent(symmetry related) part of the structure. Symmetry code: (v): -x, -y, z
	Fig. 2. Packing view projected down c. Only the C—H···O interactions have been drawn (in broken lines). H atoms not invovled in these interactions have been omitted, for clarity. Symmetry codes: (i) x + 1/4, -y + 1/4, z + 1/4; (ii) -x, -y, z + 1.

Bis(acetato-κ²O,O')(4,4'-dimethyl-2,2'-bipyridine- κ²N,N')zinc top

Crystal data top

[Zn(C₂H₃O₂)₂(C₁₂H₁₂N₂)]	F(000) = 1520
M_r = 367.71	D_x = 1.461 Mg m⁻³
Orthorhombic, Fdd2	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: F 2 -2d	Cell parameters from 1985 reflections
a = 14.4779 (5) Å	θ = 3.6–28.9°
b = 28.5700 (15) Å	µ = 1.49 mm⁻¹
c = 8.0854 (3) Å	T = 295 K
V = 3344.4 (2) Å³	Prism, white
Z = 8	0.3 × 0.3 × 0.2 mm

Data collection top

Oxford Diffraction Gemini CCD S Ultra diffractometer	1481 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.015
ω scans, thick slices	θ_max = 29.0°, θ_min = 3.6°
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)	h = −17→18
T_min = 0.65, T_max = 0.75	k = −37→17
3945 measured reflections	l = −10→5
1563 independent reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F² > 2σ(F²)] = 0.026	H-atom parameters constrained
wR(F²) = 0.068	w = 1/[σ²(F_o²) + (0.0402P)² + 1.025P] where P = (F_o² + 2F_c²)/3
S = 1.09	(Δ/σ)_max < 0.001
1563 reflections	Δρ_max = 0.28 e Å⁻³
107 parameters	Δρ_min = −0.26 e Å⁻³
1 restraint	Absolute structure: Flack (1983), 374 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.010 (16)

Crystal data top

[Zn(C₂H₃O₂)₂(C₁₂H₁₂N₂)]	V = 3344.4 (2) Å³
M_r = 367.71	Z = 8
Orthorhombic, Fdd2	Mo Kα radiation
a = 14.4779 (5) Å	µ = 1.49 mm⁻¹
b = 28.5700 (15) Å	T = 295 K
c = 8.0854 (3) Å	0.3 × 0.3 × 0.2 mm

Data collection top

Oxford Diffraction Gemini CCD S Ultra diffractometer	1563 independent reflections
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)	1481 reflections with I > 2σ(I)
T_min = 0.65, T_max = 0.75	R_int = 0.015
3945 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.026	H-atom parameters constrained
wR(F²) = 0.068	Δρ_max = 0.28 e Å⁻³
S = 1.09	Δρ_min = −0.26 e Å⁻³
1563 reflections	Absolute structure: Flack (1983), 374 Friedel pairs
107 parameters	Absolute structure parameter: 0.010 (16)
1 restraint

Special details top

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 (Å²) top

	x	y	z	U_iso*/U_eq
Zn1	0	0	0.08552 (5)	0.04845 (13)
O1	−0.10026 (14)	0.03972 (8)	−0.0279 (3)	0.0745 (6)
N1	0.02563 (14)	0.04418 (7)	0.2846 (2)	0.0456 (4)
O2	−0.12535 (18)	−0.03328 (9)	−0.0599 (3)	0.0843 (7)
C4	0.01794 (12)	0.05180 (7)	0.5779 (5)	0.0421 (5)
H4	0.0071	0.038	0.6803	0.051*
C7	−0.14861 (19)	0.00731 (10)	−0.0837 (4)	0.0548 (7)
C5	0.01168 (12)	0.02544 (8)	0.4354 (3)	0.0361 (4)
C8	−0.2331 (2)	0.01806 (14)	−0.1800 (9)	0.0900 (14)
H8B	−0.2777	0.0328	−0.1093	0.135*
H8C	−0.2584	−0.0104	−0.2238	0.135*
H8A	−0.2178	0.0388	−0.2694	0.135*
C3	0.04052 (15)	0.09917 (8)	0.5683 (4)	0.0502 (5)
C1	0.0483 (2)	0.08971 (10)	0.2769 (4)	0.0604 (7)
H1	0.0586	0.103	0.1735	0.073*
C2	0.05697 (19)	0.11722 (9)	0.4128 (4)	0.0607 (7)
H2	0.0741	0.1484	0.401	0.073*
C6	0.0449 (2)	0.12828 (10)	0.7225 (4)	0.0719 (9)
H6A	0.0721	0.1103	0.8101	0.108*
H6C	−0.0164	0.1376	0.7538	0.108*
H6B	0.0818	0.1556	0.7024	0.108*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Zn1	0.04289 (17)	0.0737 (3)	0.02871 (17)	0.01368 (17)	0	0
O1	0.0622 (11)	0.0907 (14)	0.0706 (15)	−0.0028 (10)	−0.0158 (11)	−0.0093 (12)
N1	0.0478 (10)	0.0549 (11)	0.0342 (11)	0.0047 (8)	0.0032 (8)	0.0080 (8)
O2	0.0909 (16)	0.0871 (15)	0.0749 (17)	0.0313 (12)	−0.0146 (13)	−0.0022 (13)
C4	0.0424 (11)	0.0480 (10)	0.0361 (11)	0.0034 (8)	−0.0042 (16)	0.0013 (12)
C7	0.0399 (12)	0.0850 (19)	0.0393 (14)	0.0085 (11)	0.0013 (10)	−0.0056 (13)
C5	0.0329 (9)	0.0459 (12)	0.0296 (11)	0.0036 (7)	−0.0017 (8)	0.0031 (9)
C8	0.061 (2)	0.109 (3)	0.100 (4)	0.0012 (17)	−0.037 (3)	0.017 (3)
C3	0.0452 (10)	0.0462 (11)	0.0593 (16)	0.0006 (9)	−0.0095 (12)	−0.0025 (12)
C1	0.0654 (15)	0.0602 (15)	0.0557 (18)	−0.0014 (12)	0.0060 (12)	0.0240 (13)
C2	0.0621 (16)	0.0440 (12)	0.076 (2)	−0.0032 (11)	−0.0005 (14)	0.0087 (14)
C6	0.080 (2)	0.0559 (15)	0.079 (2)	−0.0007 (14)	−0.0190 (17)	−0.0158 (16)

Geometric parameters (Å, º) top

Zn1—O1ⁱ	2.058 (2)	C4—H4	0.93
Zn1—O1	2.058 (2)	C7—C8	1.482 (5)
Zn1—N1	2.079 (2)	C5—C5ⁱ	1.493 (4)
Zn1—N1ⁱ	2.079 (2)	C8—H8B	0.96
Zn1—O2	2.362 (3)	C8—H8C	0.96
Zn1—O2ⁱ	2.362 (3)	C8—H8A	0.96
Zn1—C7	2.558 (3)	C3—C2	1.380 (4)
Zn1—C7ⁱ	2.558 (3)	C3—C6	1.500 (4)
O1—C7	1.246 (3)	C1—C2	1.357 (4)
N1—C1	1.343 (3)	C1—H1	0.93
N1—C5	1.347 (3)	C2—H2	0.93
O2—C7	1.223 (3)	C6—H6A	0.96
C4—C5	1.380 (4)	C6—H6C	0.96
C4—C3	1.394 (3)	C6—H6B	0.96

O1ⁱ—Zn1—O1	127.09 (15)	C5—C4—C3	119.9 (3)
O1ⁱ—Zn1—N1	123.63 (9)	C5—C4—H4	120
O1—Zn1—N1	97.82 (8)	C3—C4—H4	120
O1ⁱ—Zn1—N1ⁱ	97.82 (8)	O2—C7—O1	119.6 (3)
O1—Zn1—N1ⁱ	123.63 (9)	O2—C7—C8	120.4 (3)
N1—Zn1—N1ⁱ	78.52 (11)	O1—C7—C8	120.0 (3)
O1ⁱ—Zn1—O2	95.63 (10)	O2—C7—Zn1	66.85 (17)
O1—Zn1—O2	57.21 (9)	O1—C7—Zn1	52.72 (15)
N1—Zn1—O2	140.08 (8)	C8—C7—Zn1	172.7 (2)
N1ⁱ—Zn1—O2	90.22 (9)	N1—C5—C4	122.0 (2)
O1ⁱ—Zn1—O2ⁱ	57.21 (9)	N1—C5—C5ⁱ	114.92 (13)
O1—Zn1—O2ⁱ	95.63 (10)	C4—C5—C5ⁱ	123.13 (15)
N1—Zn1—O2ⁱ	90.22 (9)	C7—C8—H8B	109.5
N1ⁱ—Zn1—O2ⁱ	140.08 (8)	C7—C8—H8C	109.5
O2—Zn1—O2ⁱ	120.30 (15)	H8B—C8—H8C	109.5
O1ⁱ—Zn1—C7	113.57 (9)	C7—C8—H8A	109.5
O1—Zn1—C7	28.79 (8)	H8B—C8—H8A	109.5
N1—Zn1—C7	120.97 (8)	H8C—C8—H8A	109.5
N1ⁱ—Zn1—C7	108.27 (9)	C2—C3—C4	117.0 (3)
O2—Zn1—C7	28.42 (8)	C2—C3—C6	122.9 (2)
O2ⁱ—Zn1—C7	110.31 (10)	C4—C3—C6	120.1 (3)
O1ⁱ—Zn1—C7ⁱ	28.79 (8)	N1—C1—C2	123.1 (2)
O1—Zn1—C7ⁱ	113.57 (9)	N1—C1—H1	118.5
N1—Zn1—C7ⁱ	108.27 (9)	C2—C1—H1	118.5
N1ⁱ—Zn1—C7ⁱ	120.97 (8)	C1—C2—C3	120.4 (2)
O2—Zn1—C7ⁱ	110.31 (10)	C1—C2—H2	119.8
O2ⁱ—Zn1—C7ⁱ	28.42 (8)	C3—C2—H2	119.8
C7—Zn1—C7ⁱ	115.34 (13)	C3—C6—H6A	109.5
C7—O1—Zn1	98.50 (18)	C3—C6—H6C	109.5
C1—N1—C5	117.6 (2)	H6A—C6—H6C	109.5
C1—N1—Zn1	126.56 (18)	C3—C6—H6B	109.5
C5—N1—Zn1	115.64 (15)	H6A—C6—H6B	109.5
C7—O2—Zn1	84.73 (19)	H6C—C6—H6B	109.5

Symmetry code: (i) −x, −y, z.

Hydrogen-bond geometry (Å, º) top

Cg1 and Cg2 are the centroids of the Zn1,O1,C7,O2 and N1,C1–C5 rings, respectively.

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···O1ⁱⁱ	0.93	2.53	3.354 (4)	147
C6—H6A···O2ⁱⁱⁱ	0.96	2.56	3.438 (4)	153
C4—H4···Cg1^iv	0.93	2.99	3.874 (4)	160
C4—H4···Cg1ⁱⁱⁱ	0.93	2.96	3.766 (4)	145
C8—H8B···Cg2^v	0.96	2.96	3.804 (4)	147

Symmetry codes: (ii) x+1/4, −y+1/4, z+1/4; (iii) −x, −y, z+1; (iv) x, y, z+1; (v) x−1/2, y, z−1/2.

Experimental details

Crystal data
Chemical formula	[Zn(C₂H₃O₂)₂(C₁₂H₁₂N₂)]
M_r	367.71
Crystal system, space group	Orthorhombic, Fdd2
Temperature (K)	295
a, b, c (Å)	14.4779 (5), 28.5700 (15), 8.0854 (3)
V (Å³)	3344.4 (2)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	1.49
Crystal size (mm)	0.3 × 0.3 × 0.2

Data collection
Diffractometer	Oxford Diffraction Gemini CCD S Ultra diffractometer
Absorption correction	Multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)
T_min, T_max	0.65, 0.75
No. of measured, independent and observed [I > 2σ(I)] reflections	3945, 1563, 1481
R_int	0.015
(sin θ/λ)_max (Å⁻¹)	0.682

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.026, 0.068, 1.09
No. of reflections	1563
No. of parameters	107
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.28, −0.26
Absolute structure	Flack (1983), 374 Friedel pairs
Absolute structure parameter	0.010 (16)

Computer programs: CrysAlis PRO (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

Cg1 and Cg2 are the centroids of the Zn1,O1,C7,O2 and N1,C1–C5 rings, respectively.

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···O1ⁱ	0.93	2.53	3.354 (4)	147
C6—H6A···O2ⁱⁱ	0.96	2.56	3.438 (4)	153
C4—H4···Cg1ⁱⁱⁱ	0.93	2.99	3.874 (4)	160
C4—H4···Cg1ⁱⁱ	0.93	2.96	3.766 (4)	145
C8—H8B···Cg2^iv	0.96	2.96	3.804 (4)	147

Symmetry codes: (i) x+1/4, −y+1/4, z+1/4; (ii) −x, −y, z+1; (iii) x, y, z+1; (iv) x−1/2, y, z−1/2.

Acknowledgements

We would like to thank the Spanish Research Council (CSIC) for providing us with a free-of charge licence to the CSD System (Allen, 2002 ). FONCyT grant PME-01113 (XRD) is gratefully acknowledged.

References

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ISSN: 2056-9890

Volume 68| Part 11| November 2012| Pages m1377-m1378

doi:10.1107/S1600536812042699

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