Crystal structure of di­chlorido­bis­(dimethyl N-cyano­dithio­imino­carbonate)cobalt(II)

Diop, M.B.; Diop, L.; Oliver, A.G.

doi:10.1107/S2056989015023439

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Volume 72| Part 1| January 2016| Pages 66-68

doi:10.1107/S2056989015023439

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Crystal structure of dichloridobis(dimethyl N-cyanodithioiminocarbonate)cobalt(II)

Mouhamadou Birame Diop,^a ^* Libasse Diop ^a and Allen G. Oliver ^b

^aLaboratoire de Chimie Minérale et Analytique, Département de Chimie, Faculté des Sciences et Techniques, Université Cheikh Anta Diop, Dakar, Senegal, and ^bDepartment of Chemistry and Biochemistry, University of Notre Dame, 246, Nieuwland, Science Hall, Notre Dame, IN 46557-5670, USA
^*Correspondence e-mail: mouhamadoubdiop@gmail.com

Edited by M. Weil, Vienna University of Technology, Austria (Received 1 December 2015; accepted 6 December 2015; online 1 January 2016)

The structure of the mononuclear title complex, [{(H₃CS)₂C=NC≡ N}₂CoCl₂], consists of a Co^II atom coordinated in a distorted tetrahedral manner by two Cl⁻ ligands and the terminal N atoms of two dimethyl N-cyanodithioiminocarbonate ligands. The two organic ligands are almost coplanar, with a dihedral angle of 5.99 (6)° between their least-squares planes. The crystal packing features pairs of inversion-related complexes that are held together through C—H⋯Cl and C—H⋯S interactions and π–π stacking [centroid-to-centroid distance = 3.515 (su?) Å]. Additional C—H⋯Cl and C—H⋯S interactions, as well as Cl⋯S contacts < 3.6 Å, consolidate the crystal packing.

Keywords: crystal structure; cobalt(II); dimethyl N-cyanodithioiminocarbonate; tetrahedral configuration.

CCDC reference: 1440755

1. Chemical context

Dimethyl N-cyanodithioiminocarbonate with its two N and two S atoms has four possible coordination sites and hence should present a high coordination ability. The behaviour of N and S atoms according to Pearson's concept as hard and soft donors, respectively, may allow coordination to both hard and soft Lewis acids. Despite this coordination property, the ligand has scarcely been studied. Only one crystalline compound with dimethyl N-cyanodithioiminocarbonate as a ligand has been reported previously (Kojić-Prodić et al., 1992 ). The structure of this latter compound contains polymeric [Cu^ICl]_n chains flanked by two N-coordinating ligands. Because of the scarcity of data on this ligand, we have initiated a study of the interactions between cobalt(II) chloride hexahydrate and dimethyl N-cyanodithioiminocarbonate which has yielded the title complex, [{(H₃CS)₂C=NC≡ N}₂CoCl₂].

2. Structural commentary

The structure of the title complex consists of a Co^II atom coordinated in a distorted tetrahedral manner by two Cl⁻ ligands and the cyanide N atoms of two dimethyl N-cyanodithioiminocarbonate ligands (Fig. 1). Co—Cl and Co—N bond lengths are within expected ranges (Table 1). The Cl—Co—Cl angle is slightly larger than an ideal tetrahedral angle whereas three of the Cl—Co—N angles are smaller and the N—Co—N angle is very close to the ideal tetrahedral angle. This is remarkable because the bulky N-cyanodithioiminocarbonate ligands might be expected to enforce a higher distortion. The coordination of the ligand's nitrile nitrogen atoms to Co^II is slightly bent (Table 1). Despite this bending, the nitrile groups retain triple-bond character, with C1≡N1 and C5≡N3 bond lengths of 1.148 (3) and 1.147 (3) Å, respectively. The angular sums of the central C atoms of the ligands (C1, C5, 360.0 and 359.98°, respectively) show the expected trigonal–planar configuration. The least-squares planes of the two dimethyl N-cyanodithioiminocarbonate ligands are almost co-planar [dihedral angle = 5.99 (6)°]. The Co^II atom lies 0.437 (2) and 0.557 (2) Å from the mean planes of the two ligands.

Table 1
Selected geometric parameters (Å, °)

Co1—N3	1.9788 (18)	Co1—Cl2	2.2159 (6)
Co1—N1	1.9791 (19)	Co1—Cl1	2.2291 (6)

N3—Co1—N1	110.03 (8)	N1—Co1—Cl1	106.68 (6)
N3—Co1—Cl2	110.81 (6)	Cl2—Co1—Cl1	114.28 (2)
N1—Co1—Cl2	108.76 (6)	C1—N1—Co1	169.31 (18)
N3—Co1—Cl1	106.16 (6)	C5—N3—Co1	167.94 (18)

Figure 1
The molecular structure of the title compound, with displacement ellipsoids for non-H atoms drawn at the 50% probability level.

3. Supramolecular features

The crystal packing features inversion-related pairs of complex molecules (Fig. 2). These pairs are arranged such that Cl1 is oriented between the H₃C—S groups of the adjacent molecule, presumably reducing steric interactions. Apart from C—H⋯Cl and C—H⋯S interactions (Table 2), π–π stacking with a centroid-to-centroid distance of 3.515 (su?) Å prevails within a pair of complex molecules. In the crystal, these pairs are arranged parallel to (110) (Fig. 2). Additional C—H⋯Cl and C—H⋯S interactions between individual pairs consolidate the crystal packing which might be influenced also by other weak contacts under 3.6 Å involving the Cl and S atoms (Table 3).

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C3—H3A⋯Cl2ⁱ	0.98	2.88	3.538 (2)	125
C4—H4A⋯Cl1ⁱⁱ	0.98	2.85	3.602 (2)	135
C4—H4C⋯Cl2ⁱⁱⁱ	0.98	2.74	3.714 (2)	177
C7—H7A⋯Cl1ⁱⁱ	0.98	2.80	3.592 (3)	138
C7—H7B⋯Cl1^iv	0.98	2.87	3.590 (3)	131
C8—H8A⋯Cl2^v	0.98	2.73	3.450 (2)	131
C8—H8B⋯S4^vi	0.98	2.95	3.910 (2)	167
C8—H8C⋯S1ⁱⁱ	0.98	2.99	3.709 (3)	131
Symmetry codes: (i) x, y, z+1; (ii) -x+1, -y+1, -z+1; (iii) -x+1, -y+2, -z+1; (iv) x+1, y, z; (v) x+1, y-1, z; (vi) -x+2, -y+1, -z.

Table 3
Intermolecular contacts under 3.6 Å

Atom 1⋯Atom 2	Distance (Å)
Cl2⋯S1ⁱ	3.3742 (11)
Cl2⋯S4ⁱⁱ	3.3814 (10)
Cl1⋯S2ⁱⁱⁱ	3.5945 (10)
Symmetry codes: (i) x, y, z − 1; (ii) x − 1, y + 1, z; (iii) −x + 1, −y + 1, −z + 1.

Figure 2
Packing diagram of the title compound viewed approximately along the c axis. Displacement ellipsoids are as in Fig. 1

4. Synthesis and crystallization

All chemicals were purchased from Aldrich (Germany) and were used as received. The title compound was prepared by mixing of CoCl₂·6H₂O (1.665 g, 7 mmol) in acetonitrile (30 ml) and dimethyl N-cyanodithioiminocarbonate (1.023 g, 7 mmol) in acetonitrile (20 ml) at room temperature. The resulting blue solution was stirred for about 2 h. Blue crystals suitable for single-crystal X-ray diffraction were obtained after six days of slow solvent evaporation at room temperature (300 K).

Infra-red bands: ν(C≡N) 2224 cm⁻¹, ν(C=N) 1458 cm⁻¹, ν(CS₂) + rocking CH₃ 1024 and 962 cm⁻¹. Melting point 398 K. Elemental analyses of C₈H₁₂Cl₂CoN₄S₄: calculated (found): C 22.75 (21.91), H 2.86 (3.43), N 13.27 (12.63), S 30.37 (29.40).

5. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 4. Methyl H atoms were allowed to rotate to maximize their contribution to the electron density and were modelled with C—H = 0.98 Å and U_iso(H) = 1.5U_eq(C).

Table 4
Experimental details

Crystal data
Chemical formula	[CoCl₂(C₄H₆N₂S₂)₂]
M_r	422.29
Crystal system, space group	Triclinic, P $[\overline{1}]$
Temperature (K)	120
a, b, c (Å)	8.8533 (10), 8.8722 (10), 11.2487 (14)
α, β, γ (°)	72.823 (3), 87.281 (4), 80.072 (3)
V (Å³)	831.51 (17)
Z	2
Radiation type	Mo Kα
μ (mm⁻¹)	1.85
Crystal size (mm)	0.17 × 0.15 × 0.10

Data collection
Diffractometer	Bruker Kappa X8 APEXII
Absorption correction	Numerical (SADABS; Krause et al., 2015 )
T_min, T_max	0.757, 0.963
No. of measured, independent and observed [I > 2σ(I)] reflections	12851, 4139, 3566
R_int	0.028
(sin θ/λ)_max (Å⁻¹)	0.669

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.033, 0.087, 1.09
No. of reflections	4139
No. of parameters	176
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.11, −0.50
Computer programs: APEX2 and SAINT (Bruker, 2014 ), SHELXT2014 (Sheldrick, 2015a ), SHELXL2014 (Sheldrick, 2015b ), XP in SHELXTL (Sheldrick, 2008 ), Mercury (Macrae et al., 2006 ) and publCIF (Westrip, 2010 ).

Supporting information

CCDC reference: 1440755

Crystal structure: contains datablock I. DOI: 10.1107/S2056989015023439/wm5249sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S2056989015023439/wm5249Isup2.hkl

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2014); cell refinement: SAINT (Bruker, 2014); data reduction: SAINT (Bruker, 2014); program(s) used to solve structure: SHELXT2014 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: XP in SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Dichloridobis(dimethyl N-cyanodithioiminocarbonate)cobalt(II) top

Crystal data top

[CoCl₂(C₄H₆N₂S₂)₂]	Z = 2
M_r = 422.29	F(000) = 426
Triclinic, P1	D_x = 1.687 Mg m⁻³
a = 8.8533 (10) Å	Mo Kα radiation, λ = 0.71073 Å
b = 8.8722 (10) Å	Cell parameters from 6476 reflections
c = 11.2487 (14) Å	θ = 2.3–28.4°
α = 72.823 (3)°	µ = 1.85 mm⁻¹
β = 87.281 (4)°	T = 120 K
γ = 80.072 (3)°	Block, blue
V = 831.51 (17) Å³	0.17 × 0.15 × 0.10 mm

Data collection top

Bruker Kappa X8 APEXII diffractometer	4139 independent reflections
Radiation source: fine-focus sealed tube	3566 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.028
Detector resolution: 8.33 pixels mm^-1	θ_max = 28.4°, θ_min = 1.9°
combination of ω and φ–scans	h = −11→11
Absorption correction: numerical (SADABS; Krause et al., 2015)	k = −11→11
T_min = 0.757, T_max = 0.963	l = −14→7
12851 measured reflections

Refinement top

Refinement on F²	Primary atom site location: real-space vector search
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.033	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.087	H-atom parameters constrained
S = 1.09	w = 1/[σ²(F_o²) + (0.0454P)² + 0.4168P] where P = (F_o² + 2F_c²)/3
4139 reflections	(Δ/σ)_max = 0.001
176 parameters	Δρ_max = 1.11 e Å⁻³
0 restraints	Δρ_min = −0.50 e Å⁻³

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.

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

	x	y	z	U_iso*/U_eq
Co1	0.32319 (3)	0.80109 (3)	0.23799 (3)	0.01930 (9)
Cl1	0.16996 (6)	0.61729 (6)	0.29242 (6)	0.02787 (13)
Cl2	0.23586 (6)	1.01243 (6)	0.08085 (5)	0.02677 (13)
S1	0.35461 (6)	0.94916 (6)	0.80748 (5)	0.02145 (12)
S2	0.53818 (6)	0.72624 (6)	0.68536 (5)	0.02235 (12)
S3	0.83867 (6)	0.41595 (6)	0.37512 (5)	0.02199 (12)
S4	0.97640 (6)	0.27842 (6)	0.17733 (5)	0.02215 (12)
N1	0.3446 (2)	0.8728 (2)	0.38617 (18)	0.0247 (4)
N2	0.3115 (2)	0.9569 (2)	0.57616 (17)	0.0223 (4)
N3	0.5233 (2)	0.6904 (2)	0.19638 (19)	0.0242 (4)
N4	0.73672 (19)	0.5076 (2)	0.14206 (18)	0.0220 (4)
C1	0.3361 (2)	0.9056 (2)	0.4779 (2)	0.0217 (4)
C2	0.3924 (2)	0.8854 (2)	0.6783 (2)	0.0206 (4)
C3	0.1932 (3)	1.1047 (3)	0.7548 (2)	0.0266 (5)
H3A	0.1614	1.1553	0.8205	0.040*
H3B	0.1081	1.0588	0.7346	0.040*
H3C	0.2217	1.1849	0.6804	0.040*
C4	0.6032 (2)	0.6665 (3)	0.8441 (2)	0.0261 (4)
H4A	0.6846	0.5730	0.8579	0.039*
H4B	0.5173	0.6391	0.9001	0.039*
H4C	0.6429	0.7547	0.8608	0.039*
C5	0.6267 (2)	0.6032 (2)	0.1776 (2)	0.0208 (4)
C6	0.8401 (2)	0.4120 (2)	0.2233 (2)	0.0201 (4)
C7	1.0010 (3)	0.2699 (3)	0.4438 (2)	0.0288 (5)
H7A	1.0052	0.2589	0.5330	0.043*
H7B	1.0951	0.3042	0.4038	0.043*
H7C	0.9915	0.1667	0.4323	0.043*
C8	0.9185 (3)	0.3104 (3)	0.0198 (2)	0.0271 (5)
H8A	0.9860	0.2358	−0.0163	0.041*
H8B	0.9255	0.4205	−0.0290	0.041*
H8C	0.8125	0.2924	0.0188	0.041*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Co1	0.01959 (14)	0.02016 (14)	0.01816 (16)	0.00228 (10)	−0.00075 (11)	−0.00863 (11)
Cl1	0.0279 (3)	0.0291 (3)	0.0300 (3)	−0.0061 (2)	0.0048 (2)	−0.0138 (2)
Cl2	0.0319 (3)	0.0244 (2)	0.0215 (3)	0.00654 (19)	−0.0057 (2)	−0.0084 (2)
S1	0.0240 (2)	0.0225 (2)	0.0175 (3)	0.00254 (19)	−0.00157 (19)	−0.0087 (2)
S2	0.0242 (2)	0.0216 (2)	0.0215 (3)	0.00096 (19)	0.0012 (2)	−0.0095 (2)
S3	0.0212 (2)	0.0245 (2)	0.0197 (3)	0.00097 (18)	0.00047 (19)	−0.0084 (2)
S4	0.0208 (2)	0.0231 (2)	0.0210 (3)	0.00428 (18)	0.00045 (19)	−0.0086 (2)
N1	0.0309 (9)	0.0249 (9)	0.0192 (9)	−0.0058 (7)	0.0009 (7)	−0.0072 (7)
N2	0.0273 (9)	0.0222 (8)	0.0175 (9)	−0.0008 (7)	−0.0002 (7)	−0.0076 (7)
N3	0.0236 (8)	0.0217 (8)	0.0266 (10)	0.0018 (7)	−0.0005 (7)	−0.0088 (7)
N4	0.0210 (8)	0.0222 (8)	0.0211 (9)	0.0025 (6)	0.0004 (7)	−0.0070 (7)
C1	0.0249 (10)	0.0194 (9)	0.0202 (11)	−0.0039 (7)	−0.0002 (8)	−0.0047 (8)
C2	0.0214 (9)	0.0202 (9)	0.0208 (11)	−0.0032 (7)	0.0032 (8)	−0.0077 (8)
C3	0.0295 (11)	0.0250 (10)	0.0239 (11)	0.0063 (8)	−0.0046 (9)	−0.0105 (9)
C4	0.0246 (10)	0.0272 (10)	0.0259 (12)	0.0043 (8)	−0.0055 (9)	−0.0109 (9)
C5	0.0231 (9)	0.0195 (9)	0.0190 (10)	−0.0020 (7)	−0.0014 (8)	−0.0049 (8)
C6	0.0198 (9)	0.0197 (9)	0.0203 (10)	−0.0013 (7)	0.0020 (8)	−0.0067 (8)
C7	0.0282 (11)	0.0317 (11)	0.0235 (12)	0.0036 (9)	−0.0040 (9)	−0.0077 (9)
C8	0.0295 (11)	0.0309 (11)	0.0199 (11)	0.0046 (9)	−0.0007 (9)	−0.0113 (9)

Geometric parameters (Å, º) top

Co1—N3	1.9788 (18)	N3—C5	1.147 (3)
Co1—N1	1.9791 (19)	N4—C5	1.306 (3)
Co1—Cl2	2.2159 (6)	N4—C6	1.321 (3)
Co1—Cl1	2.2291 (6)	C3—H3A	0.9800
S1—C2	1.708 (2)	C3—H3B	0.9800
S1—C3	1.793 (2)	C3—H3C	0.9800
S2—C2	1.726 (2)	C4—H4A	0.9800
S2—C4	1.798 (2)	C4—H4B	0.9800
S3—C6	1.718 (2)	C4—H4C	0.9800
S3—C7	1.793 (2)	C7—H7A	0.9800
S4—C6	1.714 (2)	C7—H7B	0.9800
S4—C8	1.795 (2)	C7—H7C	0.9800
N1—C1	1.148 (3)	C8—H8A	0.9800
N2—C1	1.310 (3)	C8—H8B	0.9800
N2—C2	1.314 (3)	C8—H8C	0.9800

N3—Co1—N1	110.03 (8)	H3B—C3—H3C	109.5
N3—Co1—Cl2	110.81 (6)	S2—C4—H4A	109.5
N1—Co1—Cl2	108.76 (6)	S2—C4—H4B	109.5
N3—Co1—Cl1	106.16 (6)	H4A—C4—H4B	109.5
N1—Co1—Cl1	106.68 (6)	S2—C4—H4C	109.5
Cl2—Co1—Cl1	114.28 (2)	H4A—C4—H4C	109.5
C2—S1—C3	100.97 (10)	H4B—C4—H4C	109.5
C2—S2—C4	103.59 (10)	N3—C5—N4	172.7 (2)
C6—S3—C7	103.88 (10)	N4—C6—S4	119.43 (16)
C6—S4—C8	101.50 (10)	N4—C6—S3	121.39 (15)
C1—N1—Co1	169.31 (18)	S4—C6—S3	119.16 (12)
C1—N2—C2	120.71 (18)	S3—C7—H7A	109.5
C5—N3—Co1	167.94 (18)	S3—C7—H7B	109.5
C5—N4—C6	120.10 (19)	H7A—C7—H7B	109.5
N1—C1—N2	172.7 (2)	S3—C7—H7C	109.5
N2—C2—S1	120.19 (15)	H7A—C7—H7C	109.5
N2—C2—S2	121.18 (16)	H7B—C7—H7C	109.5
S1—C2—S2	118.63 (13)	S4—C8—H8A	109.5
S1—C3—H3A	109.5	S4—C8—H8B	109.5
S1—C3—H3B	109.5	H8A—C8—H8B	109.5
H3A—C3—H3B	109.5	S4—C8—H8C	109.5
S1—C3—H3C	109.5	H8A—C8—H8C	109.5
H3A—C3—H3C	109.5	H8B—C8—H8C	109.5

C1—N2—C2—S1	−177.67 (16)	C5—N4—C6—S4	175.87 (16)
C1—N2—C2—S2	2.3 (3)	C5—N4—C6—S3	−2.8 (3)
C3—S1—C2—N2	2.6 (2)	C8—S4—C6—N4	−3.5 (2)
C3—S1—C2—S2	−177.38 (13)	C8—S4—C6—S3	175.25 (13)
C4—S2—C2—N2	−176.86 (18)	C7—S3—C6—N4	−178.88 (18)
C4—S2—C2—S1	3.11 (15)	C7—S3—C6—S4	2.43 (16)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C3—H3A···Cl2ⁱ	0.98	2.88	3.538 (2)	125
C4—H4A···Cl1ⁱⁱ	0.98	2.85	3.602 (2)	135
C4—H4C···Cl2ⁱⁱⁱ	0.98	2.74	3.714 (2)	177
C7—H7A···Cl1ⁱⁱ	0.98	2.80	3.592 (3)	138
C7—H7B···Cl1^iv	0.98	2.87	3.590 (3)	131
C8—H8A···Cl2^v	0.98	2.73	3.450 (2)	131
C8—H8B···S4^vi	0.98	2.95	3.910 (2)	167
C8—H8C···S1ⁱⁱ	0.98	2.99	3.709 (3)	131

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

Intermolecular contacts under 3.6 Å top

Atom 1···Atom 2	Distance (Å)
Cl2···S1ⁱ	3.3742 (11)
Cl2···S4ⁱⁱ	3.3814 (10)
Cl1···S2ⁱⁱⁱ	3.5945 (10)

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

Acknowledgements

The authors acknowledge the Cheikh Anta Diop University of Dakar (Sénégal) and University of Notre Dame (USA) for financial support and equipment facilities. The Dakar group thanks Dr Laurent Plasseraud (University of Burgundy, Dijon, France) for equipment support.

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