catena-Poly[[(8-amino­quinoline-κ2N,N′)cadmium]-di-μ-thio­cyanato-κ2N:S;κ2S:N-[(8-amino­quinoline-κ2N,N′)cadmium]-di-μ-chlorido]

Xu, H.; Guo, C.

doi:10.1107/S1600536811051373

metal-organic compounds

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ISSN: 2056-9890

Volume 68| Part 1| January 2012| Page m3

doi:10.1107/S1600536811051373

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catena-Poly[[(8-aminoquinoline-κ²N,N′)cadmium]-di-μ-thiocyanato-κ²N:S;κ²S:N-[(8-aminoquinoline-κ²N,N′)cadmium]-di-μ-chlorido]

Heng Xu ^a ^* and Chang Guo ^a

^aAnhui Key Laboratory of Functional Coordination Compounds, School of Chemistry and Chemical Engineering, Anqing Normal University, Anqing 246011, People's Republic of China
^*Correspondence e-mail: xuheng312@163.com

(Received 21 November 2011; accepted 29 November 2011; online 3 December 2011)

In the title compound, [CdCl(NCS)(C₉H₈N₂)]_n, the Cd^II atom is in a distorted octahedral coordination environment defined by two chloride anions, two N atoms from an 8-aminoquinoline ligand, one N atom from one thiocyanate anion and one S atom from a symmetry-related thiocyanate anion. Two Cd^II atoms are bridged by two chloride anions, forming an inversion-related Cd₂Cl₂ unit; these units are further linked through thiocyanate anions, leading to a chain structure extending parallel to [010]. Weak π–π stacking interactions with centroid–centroid distances of 3.430 (4) Å and an interplanar separation of 3.390 (3) Å between the pyridine and benzene rings link the chains into a two-dimensional network parallel to (10 $[\overline{1}]$ ). Weak intermolecular C—H⋯Cl hydrogen-bonding interactions help to consolidate the crystal packing.

Related literature

For background and applications of 8-aminoquinoline and its derivatives, see: Fritsch et al. (2006 ); Kim et al. (2004 ); Li et al. (2005 ); Macias et al. (2003 ); Bortoluzzi et al. (2006 ); Tekwami & Walker (2006 ).

Experimental

Crystal data

[CdCl(NCS)(C₉H₈N₂)]
M_r = 350.10
Triclinic, $[P \overline 1]$
a = 7.4965 (6) Å
b = 8.6245 (7) Å
c = 10.5247 (12) Å
α = 106.649 (7)°
β = 98.047 (7)°
γ = 112.561 (5)°
V = 577.53 (9) Å³
Z = 2
Mo Kα radiation
μ = 2.28 mm⁻¹
T = 293 K
0.22 × 0.20 × 0.18 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2000 ) T_min = 0.635, T_max = 0.685
5150 measured reflections
2104 independent reflections
1961 reflections with I > 2σ(I)
R_int = 0.021

Refinement

R[F² > 2σ(F²)] = 0.021
wR(F²) = 0.051
S = 1.04
2104 reflections
153 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.74 e Å⁻³
Δρ_min = −0.50 e Å⁻³

Table 1
Selected bond lengths (Å)

Cd1—N3ⁱ	2.311 (2)
Cd1—N1	2.322 (2)
Cd1—N2	2.382 (3)
Cd1—Cl1	2.5495 (8)
Cd1—S1	2.6413 (8)
Cd1—Cl1ⁱⁱ	2.8088 (7)
Symmetry codes: (i) ; (ii) .

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2⋯Cl1ⁱⁱⁱ	0.93	2.84	3.723 (4)	160
Symmetry code: (iii) .

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); 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: publCIF (Westrip, 2010 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811051373/wm2567sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811051373/wm2567Isup2.hkl

checkCIF report

Comment top

8-aminoquinoline and its derivatives are systems that have been recently focused on, because of antiprotozal and other pharmaceutical properties (Tekwami & Walker, 2006). They are also strongly fluorescent and have been employed in the analytical study of heavy metals (Fritsch et al., 2006; Macias et al., 2003). They also have been used to prepare highly conducting co-polymers (Li et al., 2005). Different functionalized molecules of 8- aminoquinoline have been recently reported (Kim et al., 2004). However, the coordination chemistry of 8-aminoquinoline, as such, is scarce (Bortoluzzi et al., 2006). We report here the crystal structure of the title compound, [CdCl(SCN)(C₉H₈N₂)]_n, (I).

As shown in Fig. 1, the asymmetric unit of (I) contains one Cd^II cation, one chloride anion and one thiocyanate anion. Each Cd^II cation is in a distorted octahedral coordination environment defined by two chloride anions, two nitrogen atoms from one 8-aminoquinoline ligand, one nitrogen atom from one thiocyanate anion and one sulfur atom from another thiocyanate anion. Two Cd^II atoms are connected by two chloride anions to form a dimer and these dimers are further bridged through two thiocyanate anions, leading to a chain structure extending parallel to [010] (Fig. 2). Moreover, weak π-π stacking interactions (centroid···centroid distances of 3.430 (4) Å and an interplanar separation of 3.390 (3) Å between pyridyl rings and benzene rings) link the chains into a two-dimensional supramolecular network in the (101) plane, which is further consolidated by intermolecular C—H···Cl hydrogen bonds to genrate a three-dimensional supramolecular structure (Fig. 3). It is interesting to note that the amino hydrogen atoms are not involved in any hydrogen bonding interactions.

Related literature top

For background and applications of 8-aminoquinoline and its derivatives, see: Fritsch et al. (2006); Kim et al. (2004); Li et al. (2005); Macias et al. (2003); Bortoluzzi et al. (2006); Tekwami & Walker (2006).

Experimental top

8-aminoquinoline (1 mmol) and potassium thiocyanate (1 mmol) in 20 ml methanol were added to a clear solution of cadmium chloride (1 mmol) in 20 ml methanol. Stirring was continued for 1 h; the colour changed to light yellow. The volume of the solution was reduced to 10 ml, filtered and kept for crystallization after addition of 2 drops of 2-methoxy ethanol. Colorless block-like crystals were obtained by slow evaporation of the solvent. Yield: 59%.

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); 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: publCIF (Westrip, 2010).

Figures top

	Fig. 1. The molecular structure of the title compound, showing the atom-labelling scheme and displacement ellipsoids drawn at the 30% probability level. [Symmetry codes: (i) -x + 1, -y - 1, -z + 1; (ii) -x + 1, -y, -z + 1.]
	Fig. 2. The crystal packing of the title compound, showing the chain structure extending parallel to [010].
	Fig. 3. A view showing part of the three-dimensional supramolecular network linked by C–H···Cl hydrogen bonds and weak π—π stacking interactions. Hydrogen bonds are shown as dashed lines.

catena-Poly[[(8-aminoquinoline-κ²N,N')cadmium]- di-µ-thiocyanato-κ²N:S;κ²S:N-[(8- aminoquinoline-κ²N,N')cadmium]-di-µ-chlorido] top

Crystal data top

[CdCl(NCS)(C₉H₈N₂)]	Z = 2
M_r = 350.10	F(000) = 340
Triclinic, P1	D_x = 2.013 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.4965 (6) Å	Cell parameters from 5150 reflections
b = 8.6245 (7) Å	θ = 2.1–25.5°
c = 10.5247 (12) Å	µ = 2.28 mm⁻¹
α = 106.649 (7)°	T = 293 K
β = 98.047 (7)°	Block, colorless
γ = 112.561 (5)°	0.22 × 0.20 × 0.18 mm
V = 577.53 (9) Å³

Data collection top

Bruker SMART CCD area-detector diffractometer	2104 independent reflections
Radiation source: sealed tube	1961 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.021
phi and ω scans	θ_max = 25.5°, θ_min = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 2000)	h = −9→9
T_min = 0.635, T_max = 0.685	k = −10→10
5150 measured reflections	l = −12→12

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)] = 0.021	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.051	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ²(F_o²) + (0.0243P)² + 0.2713P] where P = (F_o² + 2F_c²)/3
2104 reflections	(Δ/σ)_max = 0.002
153 parameters	Δρ_max = 0.74 e Å⁻³
0 restraints	Δρ_min = −0.50 e Å⁻³

Crystal data top

[CdCl(NCS)(C₉H₈N₂)]	γ = 112.561 (5)°
M_r = 350.10	V = 577.53 (9) Å³
Triclinic, P1	Z = 2
a = 7.4965 (6) Å	Mo Kα radiation
b = 8.6245 (7) Å	µ = 2.28 mm⁻¹
c = 10.5247 (12) Å	T = 293 K
α = 106.649 (7)°	0.22 × 0.20 × 0.18 mm
β = 98.047 (7)°

Data collection top

Bruker SMART CCD area-detector diffractometer	2104 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2000)	1961 reflections with I > 2σ(I)
T_min = 0.635, T_max = 0.685	R_int = 0.021
5150 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.021	0 restraints
wR(F²) = 0.051	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	Δρ_max = 0.74 e Å⁻³
2104 reflections	Δρ_min = −0.50 e Å⁻³
153 parameters

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
Cd1	0.62856 (3)	−0.10583 (2)	0.594940 (19)	0.03402 (8)
Cl1	0.56554 (12)	−0.11665 (9)	0.34743 (7)	0.04336 (17)
N1	0.7549 (3)	0.0017 (3)	0.8336 (2)	0.0356 (5)
N2	0.9449 (5)	0.1523 (4)	0.6597 (3)	0.0515 (7)
N3	0.2515 (4)	−0.6802 (3)	0.4552 (3)	0.0456 (6)
S1	0.26442 (11)	−0.34111 (9)	0.57610 (9)	0.0464 (2)
C1	0.6679 (4)	−0.0751 (4)	0.9132 (3)	0.0431 (7)
H1	0.5546	−0.1865	0.8719	0.052*
C2	0.7371 (5)	0.0024 (5)	1.0580 (3)	0.0518 (8)
H2	0.6710	−0.0569	1.1110	0.062*
C3	0.9004 (5)	0.1638 (5)	1.1190 (3)	0.0525 (8)
H3	0.9471	0.2172	1.2149	0.063*
C4	1.0010 (4)	0.2524 (4)	1.0383 (3)	0.0425 (7)
C5	1.1737 (5)	0.4201 (4)	1.0939 (3)	0.0576 (9)
H5	1.2259	0.4794	1.1893	0.069*
C6	1.2648 (5)	0.4961 (4)	1.0102 (4)	0.0610 (9)
H6	1.3781	0.6077	1.0487	0.073*
C7	1.1906 (5)	0.4087 (4)	0.8661 (4)	0.0526 (8)
H7	1.2563	0.4622	0.8101	0.063*
C8	1.0226 (4)	0.2458 (4)	0.8069 (3)	0.0394 (6)
C9	0.9235 (4)	0.1647 (3)	0.8922 (3)	0.0322 (6)
C10	0.2613 (4)	−0.5392 (4)	0.5052 (3)	0.0344 (6)
H8A	0.925 (7)	0.225 (6)	0.623 (5)	0.097 (16)*
H8B	1.026 (8)	0.108 (7)	0.629 (5)	0.110 (19)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cd1	0.03527 (12)	0.03000 (12)	0.02813 (13)	0.01083 (9)	0.00321 (9)	0.00685 (9)
Cl1	0.0617 (4)	0.0430 (4)	0.0277 (4)	0.0279 (3)	0.0119 (3)	0.0102 (3)
N1	0.0353 (12)	0.0390 (12)	0.0320 (12)	0.0179 (10)	0.0070 (10)	0.0116 (10)
N2	0.0512 (16)	0.0495 (16)	0.0336 (15)	0.0056 (13)	0.0091 (13)	0.0125 (13)
N3	0.0408 (13)	0.0354 (13)	0.0548 (16)	0.0181 (11)	0.0078 (12)	0.0098 (12)
S1	0.0342 (4)	0.0322 (3)	0.0633 (5)	0.0124 (3)	0.0163 (4)	0.0069 (3)
C1	0.0396 (15)	0.0500 (17)	0.0483 (18)	0.0219 (14)	0.0149 (14)	0.0263 (15)
C2	0.0520 (19)	0.081 (2)	0.0423 (19)	0.0389 (19)	0.0210 (16)	0.0334 (18)
C3	0.057 (2)	0.081 (2)	0.0314 (16)	0.047 (2)	0.0127 (15)	0.0168 (16)
C4	0.0407 (15)	0.0524 (17)	0.0318 (15)	0.0298 (14)	0.0017 (13)	0.0036 (13)
C5	0.0508 (19)	0.0547 (19)	0.0415 (19)	0.0243 (16)	−0.0083 (16)	−0.0088 (16)
C6	0.0453 (18)	0.0422 (17)	0.061 (2)	0.0074 (15)	−0.0031 (17)	−0.0022 (16)
C7	0.0433 (17)	0.0392 (16)	0.058 (2)	0.0078 (14)	0.0083 (16)	0.0125 (15)
C8	0.0376 (15)	0.0378 (14)	0.0349 (16)	0.0146 (12)	0.0050 (13)	0.0082 (12)
C9	0.0302 (13)	0.0328 (13)	0.0285 (14)	0.0161 (11)	0.0021 (11)	0.0043 (11)
C10	0.0237 (12)	0.0378 (15)	0.0366 (15)	0.0096 (11)	0.0064 (11)	0.0137 (12)

Geometric parameters (Å, º) top

Cd1—N3ⁱ	2.311 (2)	C1—C2	1.402 (4)
Cd1—N1	2.322 (2)	C1—H1	0.9300
Cd1—N2	2.382 (3)	C2—C3	1.345 (5)
Cd1—Cl1	2.5495 (8)	C2—H2	0.9300
Cd1—S1	2.6413 (8)	C3—C4	1.408 (5)
Cd1—Cl1ⁱⁱ	2.8088 (7)	C3—H3	0.9300
Cl1—Cd1ⁱⁱ	2.8088 (7)	C4—C5	1.406 (5)
N1—C1	1.306 (4)	C4—C9	1.421 (4)
N1—C9	1.370 (3)	C5—C6	1.352 (5)
N2—C8	1.436 (4)	C5—H5	0.9300
N2—H8A	0.87 (5)	C6—C7	1.402 (5)
N2—H8B	0.88 (5)	C6—H6	0.9300
N3—C10	1.147 (3)	C7—C8	1.367 (4)
N3—Cd1ⁱ	2.311 (2)	C7—H7	0.9300
S1—C10	1.646 (3)	C8—C9	1.413 (4)

N3ⁱ—Cd1—N1	96.56 (8)	N1—C1—H1	118.4
N3ⁱ—Cd1—N2	96.66 (11)	C2—C1—H1	118.4
N1—Cd1—N2	72.51 (9)	C3—C2—C1	119.0 (3)
N3ⁱ—Cd1—Cl1	92.72 (7)	C3—C2—H2	120.5
N1—Cd1—Cl1	161.21 (6)	C1—C2—H2	120.5
N2—Cd1—Cl1	90.24 (7)	C2—C3—C4	120.3 (3)
N3ⁱ—Cd1—S1	94.00 (6)	C2—C3—H3	119.9
N1—Cd1—S1	97.09 (6)	C4—C3—H3	119.9
N2—Cd1—S1	165.86 (8)	C5—C4—C3	123.8 (3)
Cl1—Cd1—S1	98.53 (3)	C5—C4—C9	118.6 (3)
N3ⁱ—Cd1—Cl1ⁱⁱ	172.43 (6)	C3—C4—C9	117.5 (3)
N1—Cd1—Cl1ⁱⁱ	84.41 (6)	C6—C5—C4	120.7 (3)
N2—Cd1—Cl1ⁱⁱ	90.80 (10)	C6—C5—H5	119.6
Cl1—Cd1—Cl1ⁱⁱ	88.55 (2)	C4—C5—H5	119.6
S1—Cd1—Cl1ⁱⁱ	78.43 (2)	C5—C6—C7	120.8 (3)
Cd1—Cl1—Cd1ⁱⁱ	91.45 (2)	C5—C6—H6	119.6
C1—N1—C9	119.4 (2)	C7—C6—H6	119.6
C1—N1—Cd1	124.5 (2)	C8—C7—C6	120.8 (3)
C9—N1—Cd1	115.88 (17)	C8—C7—H7	119.6
C8—N2—Cd1	112.08 (19)	C6—C7—H7	119.6
C8—N2—H8A	109 (3)	C7—C8—C9	119.5 (3)
Cd1—N2—H8A	107 (3)	C7—C8—N2	121.9 (3)
C8—N2—H8B	109 (3)	C9—C8—N2	118.6 (2)
Cd1—N2—H8B	105 (3)	N1—C9—C8	119.8 (2)
H8A—N2—H8B	116 (4)	N1—C9—C4	120.6 (3)
C10—N3—Cd1ⁱ	156.0 (2)	C8—C9—C4	119.6 (3)
C10—S1—Cd1	104.03 (9)	N3—C10—S1	177.4 (2)
N1—C1—C2	123.1 (3)

C9—N1—C1—C2	0.9 (4)	Cd1—N2—C8—C9	8.6 (4)
Cd1—N1—C1—C2	−173.5 (2)	C1—N1—C9—C8	177.8 (2)
N1—C1—C2—C3	0.2 (5)	Cd1—N1—C9—C8	−7.3 (3)
C1—C2—C3—C4	−0.6 (5)	C1—N1—C9—C4	−1.6 (4)
C2—C3—C4—C5	−179.3 (3)	Cd1—N1—C9—C4	173.23 (18)
C2—C3—C4—C9	−0.1 (4)	C7—C8—C9—N1	179.8 (3)
C3—C4—C5—C6	178.9 (3)	N2—C8—C9—N1	−1.2 (4)
C9—C4—C5—C6	−0.2 (4)	C7—C8—C9—C4	−0.7 (4)
C4—C5—C6—C7	−0.7 (5)	N2—C8—C9—C4	178.3 (3)
C5—C6—C7—C8	0.9 (5)	C5—C4—C9—N1	−179.6 (3)
C6—C7—C8—C9	−0.2 (5)	C3—C4—C9—N1	1.2 (4)
C6—C7—C8—N2	−179.2 (3)	C5—C4—C9—C8	1.0 (4)
Cd1—N2—C8—C7	−172.4 (2)	C3—C4—C9—C8	−178.2 (2)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···Cl1ⁱⁱⁱ	0.93	2.84	3.723 (4)	160

Symmetry code: (iii) x, y, z+1.

Experimental details

Crystal data
Chemical formula	[CdCl(NCS)(C₉H₈N₂)]
M_r	350.10
Crystal system, space group	Triclinic, P1
Temperature (K)	293
a, b, c (Å)	7.4965 (6), 8.6245 (7), 10.5247 (12)
α, β, γ (°)	106.649 (7), 98.047 (7), 112.561 (5)
V (Å³)	577.53 (9)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	2.28
Crystal size (mm)	0.22 × 0.20 × 0.18

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2000)
T_min, T_max	0.635, 0.685
No. of measured, independent and observed [I > 2σ(I)] reflections	5150, 2104, 1961
R_int	0.021
(sin θ/λ)_max (Å⁻¹)	0.606

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.021, 0.051, 1.04
No. of reflections	2104
No. of parameters	153
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.74, −0.50

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008), publCIF (Westrip, 2010).

Selected bond lengths (Å) top

Cd1—N3ⁱ	2.311 (2)	Cd1—Cl1	2.5495 (8)
Cd1—N1	2.322 (2)	Cd1—S1	2.6413 (8)
Cd1—N2	2.382 (3)	Cd1—Cl1ⁱⁱ	2.8088 (7)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···Cl1ⁱⁱⁱ	0.93	2.84	3.723 (4)	160

Symmetry code: (iii) x, y, z+1.

Acknowledgements

This work was supported by the Natural Science Foundation of Education Commission of Anhui Province (No. KJ2010A229)

References

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