Acetonitrile­bis­(2-methyl-1,10-phenanthroline)copper(II) tetra­fluoridoborate

Watton, S.P.

doi:10.1107/S1600536810038845

metal-organic compounds

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ISSN: 2056-9890

Volume 66| Part 11| November 2010| Page m1359

https://doi.org/10.1107/S1600536810038845

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Acetonitrilebis(2-methyl-1,10-phenanthroline)copper(II) tetrafluoridoborate

Stephen P. Watton ^a ^*

^aDepartment of Chemistry and Biochemistry, Central Connecticut State University, 1615 Stanley Street, New Britain, CT 06050, USA
^*Correspondence e-mail: wattonstp@ccsu.edu

(Received 16 September 2010; accepted 28 September 2010; online 2 October 2010)

In the title compound, [Cu(CH₃CN)(C₁₃H₁₀N₂)₂](BF₄)₂, the fivefold-coordinate Cu^II atom is located on a twofold rotation axis, imposing twofold symmetry to the complete cation. The structure exhibits disorder of the anion, which was successfully refined using a two-site model with 0.810 (3):0.190 (3) occupancy. The methyl group of the acetonitrile ligand is likewise disordered, here about the twofold rotation axis in a 1:1 ratio.

Related literature

For related structures, see: Watton (2009 ).

Experimental

Crystal data

[Cu(C₂H₃N)(C₁₃H₁₀N₂)₂](BF₄)₂
M_r = 666.67
Monoclinic, C 2/c
a = 25.0665 (11) Å
b = 8.8120 (1) Å
c = 16.8419 (14) Å
β = 131.824 (8)°
V = 2772.2 (3) Å³
Z = 4
Mo Kα radiation
μ = 0.87 mm⁻¹
T = 293 K
0.25 × 0.20 × 0.15 mm

Data collection

Oxford Diffraction Sapphire 3 CCD diffractometer
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ ) T_min = 0.784, T_max = 1
30296 measured reflections
5578 independent reflections
4442 reflections with I > 2σ(I)
R_int = 0.016

Refinement

R[F² > 2σ(F²)] = 0.040
wR(F²) = 0.120
S = 1.08
5578 reflections
219 parameters
6 restraints
H-atom parameters constrained
Δρ_max = 1.07 e Å⁻³
Δρ_min = −0.81 e Å⁻³

Data collection: CrysAlis CCD (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ ); cell refinement: CrysAlis RED (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ ); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997 ); software used to prepare material for publication: publCIF (Westrip, 2010 ).

Supporting information

Crystal structure: contains datablocks I, global, New_Global_Publ_Block. DOI: https://doi.org/10.1107/S1600536810038845/fj2341sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810038845/fj2341Isup2.hkl

checkCIF report

Comment top

The structure represents the first example of a copper coordination complex containing the 2-methyl phenanthroline ligand, and is part of a continuing study of the structural influence of substitutuents at the proximal positions of the phenanthroline ligand. The structure exhibits 2-fold rotational symmetry at the copper center, with the copper atom and ligated acetonitrile ligand being located on a twofold axis of the unit cell. The methyl groups on the phenanthroline ligand are located close to the N atom of the acetonitrile ligand, and steric interactions between the atoms are most likely responsible for the observed increase in reduction potential for the 2-methyl phenanthroline complex relative to the unsubstituted analog (James, 1961). Nevertheless, the complex does not exhibit the substantial distortion of the copper coordination sphere observed in the analogous 2,9-dimethyl complex (ref, Watton 2009). The BF₄^- counterions exhibit a two-site disorder, refinement of which indicated an approximately 81:19% occupancy of the two sites.

Related literature top

For related structures, see: James & Williams (1961); Watton (2009).

Experimental top

Crystals were grown by vapor diffusion of ether into an acetonitrile solution prepared by addition of 0.041 g (0.20 mmol, ~ 2.1 equivalents) of ligand to 0.024 g (ca 0.1 mmol, ~ 1 equivalent) of Cu(BF₄)₂.xH₂O. Yield ~40%. (It should be noted that since the composition of Cu(BF₄)₂.xH₂O is not well defined, the relative amounts of Cu^- and ligand, as well as the overall yield of the reaction are correspondingly uncertain).

Structure description top

For related structures, see: James & Williams (1961); Watton (2009).

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis RED (Oxford Diffraction, 2006); data reduction: CrysAlis RED (Oxford Diffraction, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top

	Fig. 1. ORTEP plot indicating atom labeling scheme. Labels with an "a" suffix indicate symmetry equivalents of the corresponding atom numbers. Displacement ellipsoids are shown at the 50% probability level and H atoms have been omitted for clarity. The model for anion disorder is indicated and "b" suffixes correspond to lower-occupancy (19%) positions.
	Fig. 2. The preparation of the title compound and the structure of the cation.

Acetonitrilebis(2-methyl-1,10-phenanthroline)copper(II) tetrafluoridoborate top

Crystal data top

[Cu(C₂H₃N)(C₁₃H₁₀N₂)₂](BF₄)₂	F(000) = 1348
M_r = 666.67	D_x = 1.597 Mg m⁻³
Monoclinic, C2/c	Melting point: 573 K
Hall symbol: -C2yc	Mo Kα radiation, λ = 0.71073 Å
a = 25.0665 (11) Å	Cell parameters from 18534 reflections
b = 8.8120 (1) Å	θ = 3.8–34.6°
c = 16.8419 (14) Å	µ = 0.87 mm⁻¹
β = 131.824 (8)°	T = 293 K
V = 2772.2 (3) Å³	Block, green
Z = 4	0.25 × 0.2 × 0.15 mm

Data collection top

Oxford Diffraction Sapphire 3 CCD diffractometer	5578 independent reflections
Radiation source: fine-focus sealed tube	4442 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.016
ω scans	θ_max = 34.7°, θ_min = 4.0°
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006)	h = −39→40
T_min = 0.784, T_max = 1	k = −14→13
30296 measured reflections	l = −26→26

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)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.120	H-atom parameters constrained
S = 1.08	w = 1/[σ²(F_o²) + (0.0639P)² + 2.765P] where P = (F_o² + 2F_c²)/3
5578 reflections	(Δ/σ)_max < 0.001
219 parameters	Δρ_max = 1.07 e Å⁻³
6 restraints	Δρ_min = −0.81 e Å⁻³

Crystal data top

[Cu(C₂H₃N)(C₁₃H₁₀N₂)₂](BF₄)₂	V = 2772.2 (3) Å³
M_r = 666.67	Z = 4
Monoclinic, C2/c	Mo Kα radiation
a = 25.0665 (11) Å	µ = 0.87 mm⁻¹
b = 8.8120 (1) Å	T = 293 K
c = 16.8419 (14) Å	0.25 × 0.2 × 0.15 mm
β = 131.824 (8)°

Data collection top

Oxford Diffraction Sapphire 3 CCD diffractometer	5578 independent reflections
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006)	4442 reflections with I > 2σ(I)
T_min = 0.784, T_max = 1	R_int = 0.016
30296 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.040	6 restraints
wR(F²) = 0.120	H-atom parameters constrained
S = 1.08	Δρ_max = 1.07 e Å⁻³
5578 reflections	Δρ_min = −0.81 e Å⁻³
219 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	Occ. (<1)
C1	0.13529 (8)	1.05662 (18)	0.79172 (12)	0.0273 (3)
C2	0.17740 (9)	1.0448 (2)	0.76412 (15)	0.0338 (3)
H2	0.2207	1.0967	0.8041	0.041*
C3	0.15571 (9)	0.9591 (2)	0.68020 (15)	0.0338 (3)
H3	0.1844	0.9503	0.6638	0.041*
C4	0.08932 (8)	0.88348 (17)	0.61807 (13)	0.0268 (3)
C5	0.06222 (10)	0.7871 (2)	0.52973 (15)	0.0335 (3)
H5	0.0894	0.7721	0.5111	0.040*
C6	−0.00201 (10)	0.7173 (2)	0.47264 (14)	0.0325 (3)
H6	−0.0181	0.6543	0.4162	0.039*
C7	−0.04559 (8)	0.73991 (17)	0.49864 (12)	0.0257 (3)
C8	−0.11375 (9)	0.6737 (2)	0.44131 (13)	0.0332 (3)
H8	−0.1322	0.6085	0.3847	0.040*
C9	−0.15234 (9)	0.7061 (2)	0.46972 (14)	0.0340 (3)
H9	−0.1975	0.6637	0.4322	0.041*
C10	−0.12360 (8)	0.80361 (17)	0.55573 (12)	0.0267 (3)
H10	−0.1506	0.8253	0.5740	0.032*
C11	−0.02038 (7)	0.83494 (15)	0.58437 (10)	0.0198 (2)
C12	0.04852 (7)	0.90451 (15)	0.64633 (11)	0.0205 (2)
C13	0.16252 (10)	1.1435 (2)	0.88823 (14)	0.0377 (4)
H13A	0.1605	1.2502	0.8748	0.057*
H13B	0.2112	1.1148	0.9471	0.057*
H13C	0.1335	1.1217	0.9050	0.057*
C14	0.0000	1.3587 (2)	0.7500	0.0282 (4)
C15	0.0000	1.5232 (3)	0.7500	0.0525 (9)
H15A	−0.0443	1.5595	0.7279	0.079*	0.50
H15B	0.0051	1.5595	0.7016	0.079*	0.50
H15C	0.0392	1.5595	0.8205	0.079*	0.50
Cu1	0.0000	0.99458 (2)	0.7500	0.01924 (7)
N1	0.07141 (6)	0.98891 (12)	0.73210 (10)	0.0208 (2)
N2	−0.05911 (6)	0.86627 (13)	0.61224 (9)	0.0207 (2)
N3	0.0000	1.2302 (2)	0.7500	0.0303 (4)
B1	0.18636 (13)	0.4493 (3)	0.30558 (19)	0.0314 (4)	0.810 (3)
F1	0.19869 (8)	0.38867 (18)	0.24324 (13)	0.0455 (4)	0.810 (3)
F2	0.1938 (6)	0.3381 (6)	0.3661 (9)	0.1162 (15)	0.810 (3)
F3	0.2324 (2)	0.5670 (4)	0.3570 (3)	0.0722 (10)	0.810 (3)
F4	0.1172 (3)	0.5089 (5)	0.2417 (3)	0.0696 (13)	0.810 (3)
B1B	0.1736 (6)	0.4482 (13)	0.3248 (8)	0.0314 (4)	0.190 (3)
F1B	0.1694 (4)	0.4945 (7)	0.4000 (6)	0.0455 (4)	0.190 (3)
F2B	0.193 (3)	0.306 (3)	0.363 (4)	0.1162 (15)	0.190 (3)
F3B	0.2359 (10)	0.532 (2)	0.3811 (16)	0.0722 (10)	0.190 (3)
F4B	0.1126 (13)	0.463 (3)	0.2259 (18)	0.0696 (13)	0.190 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0216 (6)	0.0254 (6)	0.0285 (7)	−0.0038 (5)	0.0140 (5)	0.0041 (5)
C2	0.0228 (6)	0.0349 (8)	0.0405 (9)	−0.0028 (6)	0.0198 (6)	0.0081 (7)
C3	0.0280 (7)	0.0370 (8)	0.0432 (9)	0.0026 (6)	0.0265 (7)	0.0097 (7)
C4	0.0284 (6)	0.0272 (6)	0.0321 (7)	0.0056 (5)	0.0233 (6)	0.0083 (5)
C5	0.0408 (8)	0.0371 (8)	0.0385 (8)	0.0077 (7)	0.0331 (8)	0.0055 (7)
C6	0.0425 (9)	0.0337 (8)	0.0309 (7)	0.0045 (6)	0.0284 (7)	−0.0005 (6)
C7	0.0298 (6)	0.0244 (6)	0.0234 (6)	0.0008 (5)	0.0179 (6)	−0.0015 (5)
C8	0.0348 (8)	0.0312 (7)	0.0282 (7)	−0.0057 (6)	0.0188 (6)	−0.0093 (6)
C9	0.0271 (7)	0.0333 (8)	0.0340 (8)	−0.0096 (6)	0.0173 (6)	−0.0112 (6)
C10	0.0222 (6)	0.0266 (6)	0.0303 (7)	−0.0040 (5)	0.0171 (6)	−0.0049 (5)
C11	0.0214 (5)	0.0176 (5)	0.0208 (5)	0.0013 (4)	0.0143 (5)	0.0014 (4)
C12	0.0208 (5)	0.0194 (5)	0.0230 (6)	0.0018 (4)	0.0153 (5)	0.0041 (4)
C13	0.0314 (8)	0.0371 (8)	0.0319 (8)	−0.0150 (7)	0.0158 (7)	−0.0063 (6)
C14	0.0373 (11)	0.0202 (8)	0.0382 (11)	0.000	0.0298 (10)	0.000
C15	0.068 (2)	0.0182 (10)	0.100 (3)	0.000	0.068 (2)	0.000
Cu1	0.01965 (11)	0.01729 (11)	0.02048 (11)	0.000	0.01326 (9)	0.000
N1	0.0189 (5)	0.0198 (5)	0.0218 (5)	−0.0012 (4)	0.0128 (4)	0.0020 (4)
N2	0.0198 (5)	0.0192 (5)	0.0235 (5)	−0.0016 (4)	0.0146 (4)	−0.0016 (4)
N3	0.0415 (10)	0.0213 (8)	0.0366 (10)	0.000	0.0296 (9)	0.000
B1	0.0278 (10)	0.0394 (11)	0.0316 (10)	0.0043 (8)	0.0217 (8)	0.0098 (9)
F1	0.0439 (7)	0.0483 (8)	0.0544 (9)	−0.0133 (6)	0.0370 (7)	−0.0170 (6)
F2	0.1160 (18)	0.129 (3)	0.153 (2)	0.061 (3)	0.1105 (19)	0.109 (3)
F3	0.0757 (12)	0.081 (2)	0.098 (2)	−0.0216 (14)	0.0735 (16)	−0.0299 (17)
F4	0.0408 (10)	0.124 (4)	0.0501 (17)	0.040 (2)	0.0330 (13)	0.0346 (19)
B1B	0.0278 (10)	0.0394 (11)	0.0316 (10)	0.0043 (8)	0.0217 (8)	0.0098 (9)
F1B	0.0439 (7)	0.0483 (8)	0.0544 (9)	−0.0133 (6)	0.0370 (7)	−0.0170 (6)
F2B	0.1160 (18)	0.129 (3)	0.153 (2)	0.061 (3)	0.1105 (19)	0.109 (3)
F3B	0.0757 (12)	0.081 (2)	0.098 (2)	−0.0216 (14)	0.0735 (16)	−0.0299 (17)
F4B	0.0408 (10)	0.124 (4)	0.0501 (17)	0.040 (2)	0.0330 (13)	0.0346 (19)

Geometric parameters (Å, º) top

C1—N1	1.3356 (18)	C12—N1	1.3652 (18)
C1—C2	1.413 (2)	C13—H13A	0.9600
C1—C13	1.488 (2)	C13—H13B	0.9600
C2—C3	1.356 (3)	C13—H13C	0.9600
C2—H2	0.9300	C14—N3	1.133 (3)
C3—C4	1.409 (2)	C14—C15	1.449 (3)
C3—H3	0.9300	C15—H15A	0.9600
C4—C12	1.3985 (19)	C15—H15B	0.9600
C4—C5	1.431 (2)	C15—H15C	0.9600
C5—C6	1.353 (3)	Cu1—N1ⁱ	2.0042 (12)
C5—H5	0.9300	Cu1—N1	2.0043 (12)
C6—C7	1.436 (2)	Cu1—N2	2.0669 (12)
C6—H6	0.9300	Cu1—N2ⁱ	2.0669 (12)
C7—C11	1.4030 (19)	Cu1—N3	2.0759 (19)
C7—C8	1.411 (2)	B1—F2	1.334 (6)
C8—C9	1.365 (3)	B1—F3	1.351 (4)
C8—H8	0.9300	B1—F1	1.384 (3)
C9—C10	1.401 (2)	B1—F4	1.397 (5)
C9—H9	0.9300	B1B—F4B	1.32 (3)
C10—N2	1.3312 (18)	B1B—F2B	1.344 (16)
C10—H10	0.9300	B1B—F3B	1.381 (15)
C11—N2	1.3589 (17)	B1B—F1B	1.399 (11)
C11—C12	1.4297 (18)

N1—C1—C2	120.27 (15)	C1—C13—H13C	109.5
N1—C1—C13	119.85 (14)	H13A—C13—H13C	109.5
C2—C1—C13	119.87 (14)	H13B—C13—H13C	109.5
C3—C2—C1	121.05 (15)	N3—C14—C15	180.000 (3)
C3—C2—H2	119.5	C14—C15—H15A	109.5
C1—C2—H2	119.5	C14—C15—H15B	109.5
C2—C3—C4	119.43 (15)	H15A—C15—H15B	109.5
C2—C3—H3	120.3	C14—C15—H15C	109.5
C4—C3—H3	120.3	H15A—C15—H15C	109.5
C12—C4—C3	117.02 (15)	H15B—C15—H15C	109.5
C12—C4—C5	118.98 (14)	N1ⁱ—Cu1—N1	177.15 (6)
C3—C4—C5	124.00 (14)	N1ⁱ—Cu1—N2	96.41 (5)
C6—C5—C4	121.56 (14)	N1—Cu1—N2	82.02 (5)
C6—C5—H5	119.2	N1ⁱ—Cu1—N2ⁱ	82.02 (5)
C4—C5—H5	119.2	N1—Cu1—N2ⁱ	96.41 (5)
C5—C6—C7	120.47 (15)	N2—Cu1—N2ⁱ	113.67 (7)
C5—C6—H6	119.8	N1ⁱ—Cu1—N3	91.43 (3)
C7—C6—H6	119.8	N1—Cu1—N3	91.43 (3)
C11—C7—C8	117.39 (13)	N2—Cu1—N3	123.16 (3)
C11—C7—C6	118.96 (14)	N2ⁱ—Cu1—N3	123.16 (3)
C8—C7—C6	123.65 (14)	C1—N1—C12	119.08 (13)
C9—C8—C7	119.42 (14)	C1—N1—Cu1	128.24 (11)
C9—C8—H8	120.3	C12—N1—Cu1	112.67 (9)
C7—C8—H8	120.3	C10—N2—C11	118.39 (12)
C8—C9—C10	119.64 (15)	C10—N2—Cu1	130.48 (10)
C8—C9—H9	120.2	C11—N2—Cu1	110.88 (9)
C10—C9—H9	120.2	C14—N3—Cu1	180.000 (1)
N2—C10—C9	122.38 (14)	F2—B1—F3	116.7 (6)
N2—C10—H10	118.8	F2—B1—F1	107.9 (5)
C9—C10—H10	118.8	F3—B1—F1	104.8 (2)
N2—C11—C7	122.78 (13)	F2—B1—F4	109.5 (5)
N2—C11—C12	117.02 (12)	F3—B1—F4	107.2 (3)
C7—C11—C12	120.20 (12)	F1—B1—F4	110.5 (2)
N1—C12—C4	123.06 (13)	F4B—B1B—F2B	116 (3)
N1—C12—C11	117.17 (11)	F4B—B1B—F3B	130.2 (18)
C4—C12—C11	119.77 (13)	F2B—B1B—F3B	107 (2)
C1—C13—H13A	109.5	F4B—B1B—F1B	113.1 (12)
C1—C13—H13B	109.5	F2B—B1B—F1B	94 (2)
H13A—C13—H13B	109.5	F3B—B1B—F1B	87.4 (9)

Symmetry code: (i) −x, y, −z+3/2.

Experimental details

Crystal data
Chemical formula	[Cu(C₂H₃N)(C₁₃H₁₀N₂)₂](BF₄)₂
M_r	666.67
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	293
a, b, c (Å)	25.0665 (11), 8.8120 (1), 16.8419 (14)
β (°)	131.824 (8)
V (Å³)	2772.2 (3)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.87
Crystal size (mm)	0.25 × 0.2 × 0.15

Data collection
Diffractometer	Oxford Diffraction Sapphire 3 CCD
Absorption correction	Multi-scan (CrysAlis RED; Oxford Diffraction, 2006)
T_min, T_max	0.784, 1
No. of measured, independent and observed [I > 2σ(I)] reflections	30296, 5578, 4442
R_int	0.016
(sin θ/λ)_max (Å⁻¹)	0.800

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.040, 0.120, 1.08
No. of reflections	5578
No. of parameters	219
No. of restraints	6
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.07, −0.81

Computer programs: CrysAlis CCD (Oxford Diffraction, 2006), CrysAlis RED (Oxford Diffraction, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), publCIF (Westrip, 2010).

Acknowledgements

The author thanks Dr Guy Crundwell (CCSU) for assistance with resolving the disorder present in the structure.

References

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