Crystal structures of [(μ2-L1)di­bromidodicopper(II)] dibromide and poly[[(μ2-L1)diiodido­dicopper(I)]-di-μ-iodido-dicopper(I)], where L1 is 2,5,8,11,14,17-hexa­thia-[9.9](2,6,3,5)-pyrazino­phane

Assoumatine, T.; Stoeckli-Evans, H.

doi:10.1107/S2056989020007161

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ISSN: 2056-9890

Volume 76| Part 7| July 2020| Pages 984-989

https://doi.org/10.1107/S2056989020007161

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Crystal structures of [(μ₂-L1)dibromidodicopper(II)] dibromide and poly[[(μ₂-L1)diiodidodicopper(I)]-di-μ-iodido-dicopper(I)], where L1 is 2,5,8,11,14,17-hexathia-[9.9](2,6,3,5)-pyrazinophane

Tokouré Assoumatine ^a and Helen Stoeckli-Evans ^b ^*

^aInstitute of Chemistry, University of Neuchâtel, Av. de Bellevax 51, CH-2000 Neuchâtel, Switzerland, and ^bInstitute of Physics, University of Neuchâtel, rue Emile-Argand 11, CH-2000 Neuchâtel, Switzerland
^*Correspondence e-mail: helen.stoeckli-evans@unine.ch

Edited by S. Parkin, University of Kentucky, USA (Received 20 May 2020; accepted 27 May 2020; online 2 June 2020)

The reaction of the hexathiapyrazinophane ligand, 2,5,8,11,14,17-hexathia-[9.9](2,6,3,5)-pyrazinophane (L1), with copper(II) dibromide led to the formation of a binuclear complex, [μ₂-2,5,8,11,14,17-hexathia-[9.9](2,6,3,5)-pyrazinophane]bis[bromidocopper(II)] dibromide, [Cu₂Br₂(C₁₆H₂₄N₂S₆)]Br₂, (I). The complex possesses inversion symmetry with the pyrazine ring being situated about a center of symmetry. The ligand coordinates to the copper(II) atom in a bis-tetradentate manner and the copper atom has a fivefold NS₃Br coordination environment with a distorted shape. The reaction of ligand L1 with copper(I) iodide also gave a binuclear complex, which is bridged by a Cu₂I₂ unit to form a two-dimensional coordination polymer, poly[[μ₂-2,5,8,11,14,17-hexathia-[9.9](2,6,3,5)-pyrazinophane]tetra-μ-iodido-tetracopper(I)], [Cu₄I₄(C₁₆H₂₄N₂S₆)]_n, (II). The binuclear unit possesses inversion symmetry with the pyrazine ring being located about a center of symmetry. The Cu₂I₂ unit is also located about an inversion center. The two independent copper(I) atoms are both fourfold coordinate. That coordinating to the ligand L1 in a bis-tridentate manner has an NS₂I coordination environment and an irregular shape, while the second copper(I) atom, where L1 coordinates in a bis-monodentate manner, has an SI₃ coordination environment with an almost perfect tetrahedral geometry. In the crystal of I, the cations and Br⁻ anions are linked by a number of C—H⋯S and C—H⋯Br hydrogen bonds, forming a supramolecular network. In the crystal of II, the two-dimensional coordination polymers lie parallel to the ab plane and there are no significant inter-layer contacts present.

Keywords: crystal structure; pyrazinophane; hexathiapyrazinophane; copper(II); copper(I); binuclear complex; two-dimensional coordination polymer; supramolecular network.

CCDC references: 2006571; 2006572

1. Chemical context

Tetrasubstituted pyrazines are interesting ligands for the formation of multi-dimensional coordination polymers and metal-organic frameworks: for example, tetra-2-pyridylpyrazine (Ouellette et al., 2004 ; Nawrot et al., 2015 ) and pyrazinetetracarboxylic acid (Masci & Thuéry, 2008 ; Zhang et al., 2014 ). In recent years a new ligand, 2,3,5,6-(4-carboxyl-tetraphenyl)pyrazine, has been used successfully to form a number of metal–organic frameworks (Wang et al., 2019 ).

A number of such ligands involving N_pyrazine and S coordination sites have been synthesized and their coordination behaviour with transition metals investigated (Assoumatine, 1999 ). The title ligand, L1 (Assoumatine & Stoeckli-Evans, 2020a ), is the third in a series of pyrazinethiophane ligands that have been shown to form chains, networks and frameworks with copper halides (Assoumatine, 1999), especially with CuI. For example, ligand L2, 3,4,8,10,11,13-hexahydro-1H,6H-bis([1,4]dithiocino)[6,7-b:6′,7′-e]pyrazine, when reacted with CuI formed a two-dimensional coordination polymer, poly[[μ₄-3,4,8,10,11,13-hexahydro-1H,6H-bis([1,4]dithiocino)[6,7-b:6′,7′-e]pyrazine]di-iodido-dicopper(I)] (Fig. 1a; Assoumatine & Stoeckli-Evans, 2020b ). Ligand L3, 5,7-dihydro-1H,3H-dithieno[3,4-b:30,40-e]pyrazine, when reacted with CuI formed a three-dimensional coordination polymer, poly[(μ₄-5,7-dihydro-1H,3H-dithieno[3,4-b:3′,4′-e]pyrazine-κ⁴N:N′:S:S′)tetra-μ₃-iodidotetracopper] (Fig. 1b; Assoumatine & Stoeckli-Evans, 2020c ). Interestingly, in compound CuI-L2 the copper atom does not coordinate to the pyrazine N atom, whereas in compound CuI-L3 one of the two independent copper atoms does coordinate to the pyrazine N atom. Herein, we report on the results of the reactions of ligand L1 with CuBr₂ and CuI, where in both cases the pyrazine N atom is involved in coordination to the copper(II) and copper(I) atoms, respectively.

Figure 1
Chemical drawings of the complexes involving CuI and ligands L2 and L3.

2. Structural commentary

The reaction of the hexathiapyrazinophane ligand, 2,5,8,11,14,17-hexathia-[9.9](2,6,3,5)-pyrazinophane (L1), with copper(II) dibromide led to the formation of a binuclear complex, [(μ₂-L1)dibromodo dicopper(II)] dibromide, (I); see Fig. 2. The complex possesses inversion symmetry with the pyrazine ring being situated about a center of symmetry. Selected bond distances and angles are given in Table 1. The ligand coordinates to the copper(II) atoms in a bis-tetradentate manner. The symmetry related Cu atoms have a fivefold NS₃Br coordination environment with a distorted shape, as indicated by the fivefold index parameter τ₅ of 0.38 (τ₅ = 0 for an ideal square-pyramidal coordination sphere, and = 1 for an ideal trigonal–pyramidal coordination sphere; Addison et al., 1984 ). There are four five-membered chelate rings; Cu1/N1/C2/C3/S1 and Cu1/N1/C1/C8/S3 which are inclined by ca 90° to chelate rings Cu1/S1/C4/C5/S2 and Cu1/S2/C6/C7/S3 (Fig. 2).

Table 1
Selected geometric parameters (Å, °) for I

Cu1—N1	2.046 (6)	Cu1—S3	2.333 (2)
Cu1—S1	2.346 (2)	Cu1—Br1	2.3672 (11)
Cu1—S2	2.4549 (18)

N1—Cu1—S1	85.26 (18)	S3—Cu1—Br1	94.97 (6)
N1—Cu1—S3	85.38 (18)	N1—Cu1—S2	104.48 (15)
S3—Cu1—S1	168.54 (7)	S1—Cu1—S2	88.79 (7)
N1—Cu1—Br1	145.45 (15)	S3—Cu1—S2	87.17 (7)
S1—Cu1—Br1	96.48 (6)	Br1—Cu1—S2	110.05 (6)

Figure 2
A view of the molecular structure of complex I, with atom labelling for the asymmetric unit; symmetry code: (i) −x + 1, −y + 1, −z. Displacement ellipsoids are drawn at the 50% probability level.

Reaction of L1 with copper(I) iodide also gave a binuclear complex, which is bridged by a Cu₂I₂ unit to form a two-dimensional coordination polymer, poly-[(μ₂-L1)diiodidodicopper(I)di(μ-iodido)dicopper(I)], (II); see Fig. 3. The binuclear complex possesses inversion symmetry with the pyrazine ring being located about a center of symmetry. The Cu₂I₂ unit is also located about an inversion center. Selected bond distances and angles are given in Table 2. The two independent copper(I) atoms, Cu1 and Cu2, are both fourfold coordinate. Atom Cu1 coordinates to the ligand L1 in a tridentate fashion and has an NS₂I coordination environment. The fourfold index parameter τ₄ is 0.77 indicating a very irregular shape (τ₄ = 1 for a perfect tetrahedral environment, 0 for a perfect square-planar environment and 0.85 for a perfect trigonal–pyramidal environment; Yang et al., 2007 ). There are three chelate rings, two of which are five-membered (Cu1/N1/C2/C3/S1 and Cu1/S1/C4/C5/S2) and one eight-membered (Cu1/N1/C1/C8/S3/C7/C6/S2). The second copper(I) atom, Cu2, coordinates to L1 in a monodentate fashion and has an SI₃ environment with an almost perfect tetrahedral geometry; here the fourfold index parameter τ₄ is 0.91.

Table 2
Selected geometric parameters (Å, °) for II

Cu1—N1	2.095 (10)	Cu2—I1	2.665 (2)
Cu1—S1	2.342 (4)	Cu2—I2	2.6166 (19)
Cu1—S2	2.331 (4)	I1—Cu2ⁱⁱ	2.675 (2)
Cu1—I2ⁱ	2.5193 (18)	Cu2—Cu2ⁱⁱ	2.663 (4)
Cu2—S3	2.359 (4)

N1—Cu1—S2	110.2 (3)	S3—Cu2—I1ⁱⁱ	99.22 (11)
N1—Cu1—S1	85.3 (3)	I2—Cu2—I1ⁱⁱ	112.01 (7)
S2—Cu1—S1	91.74 (14)	I1—Cu2—I1ⁱⁱ	120.18 (7)
N1—Cu1—I2ⁱ	121.1 (3)	Cu2—I1—Cu2ⁱⁱ	59.82 (7)
S2—Cu1—I2ⁱ	112.48 (12)	Cu1ⁱⁱⁱ—I2—Cu2	94.93 (7)
S1—Cu1—I2ⁱ	130.61 (10)	Cu2ⁱⁱ—Cu2—I1	60.27 (7)
S3—Cu2—I2	109.54 (11)	Cu2ⁱⁱ—Cu2—I1ⁱⁱ	59.91 (7)
S3—Cu2—I1	105.86 (10)	S3—Cu2—Cu2ⁱⁱ	115.75 (13)
I2—Cu2—I1	109.04 (8)	I2—Cu2—Cu2ⁱⁱ	134.68 (11)
Symmetry codes: (i) x+1, y, z; (ii) -x+1, -y+1, -z; (iii) x-1, y, z.

Figure 3
A view of the molecular structure of complex II, with atom labelling for the asymmetric unit; symmetry codes: (i) x + 1, y, z; (ii) −x + 1, −y + 1, −z; (iii) x − 1, y, z. Displacement ellipsoids are drawn at the 50% probability level. (Atom Cu1 is green, while atom Cu2 is orange.)

The Cu1—N1 bond lengths in the two complexes, 2.046 (6) Å in I and 2.095 (10) Å in II, are significantly different (Linden, 2020 ). They have a difference of 0.049 (12) Å so differ by 4.1σ (i.e., 0.049 Å = 0.012 Å × 4.1). In I, the bond length Cu1—S2 of 2.455 (2) Å is significantly longer than bond lengths Cu1—S1 [2.346 (2) Å] and Cu1—S3 [2.333 (2) Å]. In II, bond lengths Cu1—S1 and Cu1—S2, involving the five-membered chelate rings, viz. 2.342 (4) and 2.331 (4) Å, respectively, are similar to those in I, while bond length Cu2—S3 [2.359 (4) Å] is only slightly longer. The bridging Cu2—Cu2ⁱ distance in the Cu₂I₂ unit in II is 2.663 (4) Å (Table 2), considerably shorter than the same distance observed in complex CuI-L2 [2.776 (1) Å] [Fig. 1a; Assoumatine & Stoeckli-Evans, 2020b].

3. Supramolecular features

In the crystal of I, the cations are linked by pairs of C6—H6B⋯S1ⁱ hydrogen bonds to form chains along the a-axis direction. Chains are also formed along the b-axis direction via C5—H5A⋯S3ⁱⁱ hydrogen bonds (Table 3). These interactions result in the formation of a supramolecular network that lies parallel to the ab plane (Fig. 4). There are also a large number of C—H⋯Br contacts present involving the anion, Br2⁻, strengthening the supramolecular network (Fig. 5 and Table 3). There are no significant inter-layer contacts present in the crystal.

Table 3
Hydrogen-bond geometry (Å, °) for I

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C6—H6B⋯S1ⁱ	0.98	2.85	3.753 (9)	154
C5—H5A⋯S3ⁱⁱ	0.98	2.81	3.634 (8)	143
C3—H3A⋯Br2ⁱⁱⁱ	0.98	2.86	3.814 (8)	165
C3—H3B⋯Br2ⁱⁱ	0.98	2.83	3.770 (7)	160
C5—H5B⋯Br2^iv	0.98	2.87	3.821 (7)	164
C7—H7B⋯Br2ⁱ	0.98	2.82	3.646 (8)	142
C8—H8A⋯Br2ⁱ	0.98	2.84	3.769 (9)	159
C8—H8B⋯Br2^v	0.98	2.89	3.713 (7)	142
Symmetry codes: (i) x+1, y, z; (ii) x, y+1, z; (iii) -x, -y+1, -z; (iv) -x+1, -y+1, -z; (v) -x+1, -y, -z.

Figure 4
A view along the c axis of the crystal packing of I. The C—H⋯S hydrogen bonds are shown as dashed lines (see Table 3

). For clarity, the Br⁻ anion and the H atoms not involved in these intermolecular interactions have been omitted.

Figure 5
A view along the b axis of the crystal packing of I. The C—H⋯S and C—H⋯Br⁻ hydrogen bonds (Table 3

) are shown as dashed lines (see Table 3

). For clarity, only the H atoms involved in these intermolecular interactions have been included.

In the crystal of II, the two-dimensional coordination polymers lie parallel to the (001) plane, as shown in Fig. 6. There are no significant inter-layer contacts present in the crystal (Fig. 7).

Figure 6
A view along the c axis of the two-dimensional structure of complex II. For clarity, H atoms have been omitted.

Figure 7
A view along the a axis of the crystal packing of complex II. For clarity, H atoms have been omitted.

4. Database survey

A search of the Cambridge Structural Database (CSD, Version 5.41, last update March 2020; Groom et al., 2016 ) for tri- or hexa-thiabenzenophane ligands gave only three hits. They include the trithiabenzenophane ligand, 2,5,8-trithia(9)-m-benzenophane (CSD refcode VEYNES; Groot & Loeb, 1990 ), and a palladium and a silver complex of the same ligand, viz. dichloro[2,5,8-trithia(9)-m-benzenophane]palladium(II) (KOMNOP; Groot et al., 1991 ), a mononuclear complex, and poly[[2,5,8-trithia(9)-m-cyclophane-S,S′,S′′]silver(I) trifluoromethylsulfonate acetonitrile solvate] (ZIDPEH; Casabo et al., 1995 ), a two-dimensional coordination polymer. In KOMNOP, the ligand coordinates in a bidentate manner. The palladium(II) atom is fourfold S₂Cl₂ coordinate with a square-planar environment (index parameter τ₄ is 0.04), In ZIDPEH, the ligand coordinates in a bridging μ₃-monodentate manner. The silver(I) atom is fivefold NOS₃ coordinate with an irregular shape (index parameter τ₅ is 0.56).

A search for benzenophane ligands similar to L2 and L3 gave zero hits for L2 and ten hits for L3. The latter compounds have been compared in a recent article (Assoumatine & Stoeckli-Evans, 2020d ), which also describes the syntheses and crystal structures of both L2 and L3.

5. Synthesis and crystallization

The synthesis and crystal structure of the ligand 2,5,8,11,14,17-hexathia-[9.9](2,6,3,5)-pyrazinophane (L1), have been reported (Assoumatine & Stoeckli-Evans, 2020a).

Synthesis of complex [(μ₂-L1)dibromodo dicopper(II)] dibromide (I): A solution of L1 (15 mg, 0.03 mmol) in CHCl₃ (10 ml) was introduced into a 16 mm diameter glass tube and layered with MeCN (2 ml) as a buffer zone. Then a solution of CuBr₂ (7 mg, 0.03 mmol) in MeCN (5 ml) was added gently to avoid possible mixing. The glass tube was sealed and left in the dark at room temperature for at least 3 weeks, whereupon brown crystals of complex I were isolated in the buffer zone.

Synthesis of complex poly-[(μ₂-L1)diiodido-dicopper(I)-di(μ-iodido)-dicopper(I)] (II): A solution of L1 (15 mg, 0.03 mmol) in CH₂Cl₂ (5 ml) was introduced into a 16 mm diameter glass tube and layered with MeCN (2 ml) as a buffer zone. A solution of CuI (6 mg, 0.03 mmol) in MeCN (5 ml) was added gently to avoid possible mixing. The glass tube was sealed under an atmosphere of nitrogen and left in the dark at room temperature for at least 3 weeks, whereupon small orange crystals of complex II were isolated in the buffer zone.

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 4. The C-bound H atoms were included in calculated positions and treated as riding on their parent atoms: C—H = 0.98 Å for I and 0.97 Å for II, with U_iso(H) = 1.2U_eq(C).

Table 4
Experimental details

	I	II
Crystal data
Chemical formula	[Cu₂Br₂(C₁₆H₂₄N₂S₆)]Br₂	[Cu₄I₄(C₁₆H₂₄N₂S₆)]
M_r	883.45	1198.49
Crystal system, space group	Triclinic, P $[\overline{1}]$	Triclinic, P $[\overline{1}]$
Temperature (K)	223	293
a, b, c (Å)	7.2090 (7), 8.1422 (8), 12.3904 (14)	7.7713 (8), 8.9456 (9), 11.2464 (14)
α, β, γ (°)	71.842 (12), 74.702 (12), 72.694 (12)	106.839 (13), 104.644 (13), 93.412 (12)
V (Å³)	647.93 (13)	716.53 (15)
Z	1	1
Radiation type	Mo Kα	Mo Kα
μ (mm⁻¹)	8.30	7.69
Crystal size (mm)	0.20 × 0.20 × 0.03	0.30 × 0.20 × 0.05

Data collection
Diffractometer	Stoe IPDS 1	Stoe IPDS 1
Absorption correction	Multi-scan (MULABS; Spek, 2020 )	Multi-scan (MULABS; Spek, 2020)
T_min, T_max	0.421, 1.000	0.435, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	5057, 2320, 1843	5260, 2505, 1698
R_int	0.076	0.100
(sin θ/λ)_max (Å⁻¹)	0.613	0.606

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.060, 0.153, 1.01	0.070, 0.183, 0.95
No. of reflections	2320	2505
No. of parameters	106	127
H-atom treatment	H-atom parameters constrained	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.65, −1.67	2.25, −2.58
Computer programs: EXPOSE, CELL and INTEGRATE in IPDS-I (Stoe & Cie, 1997 ), SHELXS97 (Sheldrick, 2008 ), Mercury (Macrae et al., 2020 ), SHELXL2018/3 (Sheldrick, 2015 ), PLATON (Spek, 2020) and publCIF (Westrip, 2010 ).

Intensity data were measured using a STOE IPDS-1 one-circle diffractometer. For the triclinic system often only 93% of the Ewald sphere is accessible, which explains why the alerts diffrn_reflns_laue_measured_fraction_full value (0.94) below minimum (0.95) for both compounds I and II are given. This involves 145 random reflections out of the expected 2336 for the IUCr cutoff limit of sin θ/λ = 0.60 for I, and 155 random reflections out of the expected 2600 reflections for II. The residual electron-density peaks are approximately 1Å from the halogen atoms in both structures.

Supporting information

CCDC references: 2006571; 2006572

Crystal structure: contains datablocks I, II, Global. DOI: https://doi.org/10.1107/S2056989020007161/pk2634sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989020007161/pk2634Isup2.hkl

Structure factors: contains datablock II. DOI: https://doi.org/10.1107/S2056989020007161/pk2634IIsup3.hkl

checkCIF report

Computing details top

For both structures, data collection: EXPOSE in IPDS-I (Stoe & Cie, 1997); cell refinement: CELL in IPDS-I (Stoe & Cie, 1997); data reduction: INTEGRATE in IPDS-I (Stoe & Cie, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2018/3 (Sheldrick, 2015); molecular graphics: Mercury (Macrae et al., 2020); software used to prepare material for publication: SHELXL2018/3 (Sheldrick, 2015), PLATON (Spek, 2020) and publCIF (Westrip, 2010).

[µ₂-2,5,8,11,14,17-Hexathia-[9.9](2,6,3,5)-pyrazinophane]bis[bromidocopper(II)] dibromide (I) top

Crystal data top

[Cu₂Br₂(C₁₆H₂₄N₂S₆)]Br₂	Z = 1
M_r = 883.45	F(000) = 428
Triclinic, P1	D_x = 2.264 Mg m⁻³
a = 7.2090 (7) Å	Mo Kα radiation, λ = 0.71073 Å
b = 8.1422 (8) Å	Cell parameters from 5000 reflections
c = 12.3904 (14) Å	θ = 2.7–25.8°
α = 71.842 (12)°	µ = 8.30 mm⁻¹
β = 74.702 (12)°	T = 223 K
γ = 72.694 (12)°	Plate, brown
V = 647.93 (13) Å³	0.20 × 0.20 × 0.03 mm

Data collection top

STOE IPDS 1 diffractometer	2320 independent reflections
Radiation source: fine-focus sealed tube	1843 reflections with I > 2σ(I)
Plane graphite monochromator	R_int = 0.076
φ rotation scans	θ_max = 25.8°, θ_min = 2.7°
Absorption correction: multi-scan (MULABS; Spek, 2020)	h = −8→8
T_min = 0.421, T_max = 1.000	k = −9→9
5057 measured reflections	l = −15→15

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)] = 0.060	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.153	H-atom parameters constrained
S = 1.01	w = 1/[σ²(F_o²) + (0.1019P)²] where P = (F_o² + 2F_c²)/3
2320 reflections	(Δ/σ)_max < 0.001
106 parameters	Δρ_max = 1.65 e Å⁻³
0 restraints	Δρ_min = −1.67 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
Br1	0.19307 (12)	0.19827 (12)	0.45400 (7)	0.0328 (3)
Cu1	0.38840 (13)	0.35871 (11)	0.29477 (7)	0.0163 (3)
S1	0.1670 (3)	0.6379 (2)	0.28528 (15)	0.0215 (4)
S2	0.6115 (3)	0.4639 (2)	0.36310 (15)	0.0197 (4)
S3	0.6481 (3)	0.1120 (2)	0.27313 (15)	0.0175 (4)
N1	0.4546 (9)	0.4439 (7)	0.1184 (5)	0.0156 (7)
C1	0.5922 (11)	0.3381 (9)	0.0573 (6)	0.0156 (7)
C2	0.3618 (10)	0.6046 (9)	0.0628 (6)	0.0156 (7)
C3	0.2054 (11)	0.7229 (9)	0.1295 (6)	0.0202 (16)
H3A	0.080095	0.744824	0.104611	0.024*
H3B	0.240502	0.837592	0.109580	0.024*
C4	0.3042 (11)	0.7561 (10)	0.3270 (6)	0.0213 (9)
H4A	0.262709	0.883424	0.290981	0.026*
H4B	0.267942	0.739951	0.411020	0.026*
C5	0.5303 (11)	0.6978 (9)	0.2940 (6)	0.0156 (7)
H5A	0.592228	0.768345	0.318918	0.019*
H5B	0.570091	0.717761	0.209820	0.019*
C6	0.8280 (12)	0.3836 (9)	0.2624 (6)	0.0213 (9)
H6A	0.808898	0.438922	0.182395	0.026*
H6B	0.945536	0.410333	0.272072	0.026*
C7	0.8506 (11)	0.1809 (9)	0.2918 (7)	0.0223 (16)
H7A	0.867485	0.130400	0.372431	0.027*
H7B	0.971846	0.130109	0.243159	0.027*
C8	0.6904 (12)	0.1574 (9)	0.1173 (6)	0.0213 (9)
H8A	0.833237	0.139237	0.087755	0.026*
H8B	0.644904	0.070380	0.097392	0.026*
Br2	0.21653 (11)	0.20772 (10)	0.02398 (7)	0.0267 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.0270 (5)	0.0335 (5)	0.0267 (5)	−0.0116 (4)	−0.0043 (3)	0.0114 (3)
Cu1	0.0194 (5)	0.0085 (5)	0.0194 (5)	−0.0036 (4)	−0.0032 (4)	−0.0013 (3)
S1	0.0215 (10)	0.0172 (10)	0.0201 (9)	0.0018 (8)	−0.0013 (7)	−0.0053 (7)
S2	0.0281 (10)	0.0115 (9)	0.0223 (9)	−0.0028 (8)	−0.0095 (8)	−0.0060 (7)
S3	0.0270 (10)	0.0051 (8)	0.0195 (8)	−0.0025 (8)	−0.0085 (7)	0.0005 (6)
N1	0.0223 (18)	0.0065 (15)	0.0219 (16)	−0.0034 (14)	−0.0088 (13)	−0.0053 (12)
C1	0.0223 (18)	0.0065 (15)	0.0219 (16)	−0.0034 (14)	−0.0088 (13)	−0.0053 (12)
C2	0.0223 (18)	0.0065 (15)	0.0219 (16)	−0.0034 (14)	−0.0088 (13)	−0.0053 (12)
C3	0.029 (4)	0.012 (4)	0.014 (3)	0.008 (3)	−0.007 (3)	−0.006 (3)
C4	0.031 (3)	0.011 (2)	0.022 (2)	−0.002 (2)	−0.0101 (19)	−0.0047 (17)
C5	0.0223 (18)	0.0065 (15)	0.0219 (16)	−0.0034 (14)	−0.0088 (13)	−0.0053 (12)
C6	0.031 (3)	0.011 (2)	0.022 (2)	−0.002 (2)	−0.0101 (19)	−0.0047 (17)
C7	0.024 (4)	0.011 (4)	0.035 (4)	0.002 (3)	−0.020 (3)	−0.004 (3)
C8	0.031 (3)	0.011 (2)	0.022 (2)	−0.002 (2)	−0.0101 (19)	−0.0047 (17)
Br2	0.0247 (4)	0.0210 (4)	0.0385 (5)	−0.0073 (4)	−0.0041 (3)	−0.0127 (3)

Geometric parameters (Å, º) top

Cu1—N1	2.046 (6)	C2—C3	1.497 (9)
Cu1—S1	2.346 (2)	C3—H3A	0.9800
Cu1—S2	2.4549 (18)	C3—H3B	0.9800
Cu1—S3	2.333 (2)	C4—C5	1.536 (10)
Cu1—Br1	2.3672 (11)	C4—H4A	0.9800
S1—C3	1.811 (7)	C4—H4B	0.9800
S1—C4	1.822 (7)	C5—H5A	0.9800
S2—C6	1.815 (8)	C5—H5B	0.9800
S2—C5	1.814 (7)	C6—C7	1.542 (9)
S3—C7	1.802 (7)	C6—H6A	0.9800
S3—C8	1.808 (7)	C6—H6B	0.9800
N1—C1	1.342 (9)	C7—H7A	0.9800
N1—C2	1.340 (9)	C7—H7B	0.9800
C1—C2ⁱ	1.394 (10)	C8—H8A	0.9800
C1—C8	1.482 (11)	C8—H8B	0.9800

N1—Cu1—S1	85.26 (18)	S1—C3—H3B	108.4
N1—Cu1—S3	85.38 (18)	H3A—C3—H3B	107.5
S3—Cu1—S1	168.54 (7)	C5—C4—S1	115.1 (5)
N1—Cu1—Br1	145.45 (15)	C5—C4—H4A	108.5
S1—Cu1—Br1	96.48 (6)	S1—C4—H4A	108.5
S3—Cu1—Br1	94.97 (6)	C5—C4—H4B	108.5
N1—Cu1—S2	104.48 (15)	S1—C4—H4B	108.5
S1—Cu1—S2	88.79 (7)	H4A—C4—H4B	107.5
S3—Cu1—S2	87.17 (7)	C4—C5—S2	109.4 (4)
Br1—Cu1—S2	110.05 (6)	C4—C5—H5A	109.8
C3—S1—C4	102.4 (3)	S2—C5—H5A	109.8
C3—S1—Cu1	98.5 (2)	C4—C5—H5B	109.8
C4—S1—Cu1	101.4 (3)	S2—C5—H5B	109.8
C6—S2—C5	104.4 (3)	H5A—C5—H5B	108.3
C6—S2—Cu1	93.8 (2)	C7—C6—S2	105.4 (5)
C5—S2—Cu1	96.5 (2)	C7—C6—H6A	110.7
C7—S3—C8	100.9 (4)	S2—C6—H6A	110.7
C7—S3—Cu1	101.0 (2)	C7—C6—H6B	110.7
C8—S3—Cu1	97.8 (3)	S2—C6—H6B	110.7
C1—N1—C2	119.4 (6)	H6A—C6—H6B	108.8
C1—N1—Cu1	119.9 (5)	C6—C7—S3	115.5 (5)
C2—N1—Cu1	120.7 (5)	C6—C7—H7A	108.4
N1—C1—C2ⁱ	120.2 (7)	S3—C7—H7A	108.4
N1—C1—C8	119.9 (6)	C6—C7—H7B	108.4
C2ⁱ—C1—C8	119.9 (6)	S3—C7—H7B	108.4
N1—C2—C1ⁱ	120.4 (6)	H7A—C7—H7B	107.5
N1—C2—C3	120.1 (6)	C1—C8—S3	115.4 (5)
C1ⁱ—C2—C3	119.5 (7)	C1—C8—H8A	108.4
C2—C3—S1	115.3 (5)	S3—C8—H8A	108.4
C2—C3—H3A	108.4	C1—C8—H8B	108.4
S1—C3—H3A	108.4	S3—C8—H8B	108.4
C2—C3—H3B	108.4	H8A—C8—H8B	107.5

C2—N1—C1—C2ⁱ	0.2 (10)	Cu1—S1—C4—C5	30.4 (6)
Cu1—N1—C1—C2ⁱ	−179.9 (4)	S1—C4—C5—S2	−59.9 (6)
C2—N1—C1—C8	−177.6 (5)	C6—S2—C5—C4	148.0 (5)
Cu1—N1—C1—C8	2.3 (8)	Cu1—S2—C5—C4	52.4 (4)
C1—N1—C2—C1ⁱ	−0.2 (10)	C5—S2—C6—C7	−158.1 (5)
Cu1—N1—C2—C1ⁱ	179.9 (4)	Cu1—S2—C6—C7	−60.3 (5)
C1—N1—C2—C3	178.9 (6)	S2—C6—C7—S3	62.3 (6)
Cu1—N1—C2—C3	−1.0 (8)	C8—S3—C7—C6	74.9 (6)
N1—C2—C3—S1	3.6 (8)	Cu1—S3—C7—C6	−25.4 (6)
C1ⁱ—C2—C3—S1	−177.3 (5)	N1—C1—C8—S3	−11.6 (8)
C4—S1—C3—C2	99.9 (5)	C2ⁱ—C1—C8—S3	170.6 (5)
Cu1—S1—C3—C2	−3.8 (5)	C7—S3—C8—C1	−89.9 (6)
C3—S1—C4—C5	−71.0 (6)	Cu1—S3—C8—C1	13.0 (5)

Symmetry code: (i) −x+1, −y+1, −z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C6—H6B···S1ⁱⁱ	0.98	2.85	3.753 (9)	154
C5—H5A···S3ⁱⁱⁱ	0.98	2.81	3.634 (8)	143
C3—H3A···Br2^iv	0.98	2.86	3.814 (8)	165
C3—H3B···Br2ⁱⁱⁱ	0.98	2.83	3.770 (7)	160
C5—H5B···Br2ⁱ	0.98	2.87	3.821 (7)	164
C7—H7B···Br2ⁱⁱ	0.98	2.82	3.646 (8)	142
C8—H8A···Br2ⁱⁱ	0.98	2.84	3.769 (9)	159
C8—H8B···Br2^v	0.98	2.89	3.713 (7)	142

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

Poly[[µ₂-2,5,8,11,14,17-hexathia-[9.9](2,6,3,5)-pyrazinophane]tetra-µ-iodido-tetracopper(I)] (II) top

Crystal data top

[Cu₄I₄(C₁₆H₂₄N₂S₆)]	Z = 1
M_r = 1198.49	F(000) = 558
Triclinic, P1	D_x = 2.777 Mg m⁻³
a = 7.7713 (8) Å	Mo Kα radiation, λ = 0.71073 Å
b = 8.9456 (9) Å	Cell parameters from 4652 reflections
c = 11.2464 (14) Å	θ = 2.0–25.8°
α = 106.839 (13)°	µ = 7.69 mm⁻¹
β = 104.644 (13)°	T = 293 K
γ = 93.412 (12)°	Plate, orange
V = 716.53 (15) Å³	0.30 × 0.20 × 0.05 mm

Data collection top

STOE IPDS 1 diffractometer	2505 independent reflections
Radiation source: fine-focus sealed tube	1698 reflections with I > 2σ(I)
Plane graphite monochromator	R_int = 0.100
φ rotation scans	θ_max = 25.5°, θ_min = 2.4°
Absorption correction: multi-scan (MULABS; Spek, 2020)	h = −9→9
T_min = 0.435, T_max = 1.000	k = −10→10
5260 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)] = 0.070	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.183	H-atom parameters constrained
S = 0.95	w = 1/[σ²(F_o²) + (0.110P)²] where P = (F_o² + 2F_c²)/3
2505 reflections	(Δ/σ)_max < 0.001
127 parameters	Δρ_max = 2.25 e Å⁻³
0 restraints	Δρ_min = −2.58 e Å⁻³

Special details top

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

	x	y	z	U_iso*/U_eq
I1	0.73534 (12)	0.70224 (11)	0.11663 (9)	0.0396 (3)
I2	0.34990 (12)	0.56223 (11)	0.29340 (9)	0.0370 (3)
Cu1	1.2404 (2)	0.2890 (2)	0.28830 (16)	0.0332 (4)
Cu2	0.5027 (2)	0.4653 (2)	0.10778 (18)	0.0415 (5)
S1	1.3999 (4)	0.0851 (4)	0.3255 (3)	0.0326 (8)
S2	1.1079 (5)	0.2923 (4)	0.4531 (3)	0.0349 (8)
S3	0.6749 (4)	0.2663 (4)	0.1450 (3)	0.0296 (7)
N1	1.0914 (12)	0.1189 (12)	0.1149 (10)	0.025 (2)
C1	0.9371 (16)	0.1373 (15)	0.0368 (12)	0.0238 (18)
C2	1.1538 (15)	−0.0213 (15)	0.0762 (11)	0.0238 (18)
C3	1.3271 (19)	−0.0448 (18)	0.1606 (13)	0.038 (3)
H3A	1.421167	−0.033142	0.120089	0.046*
H3B	1.314897	−0.152610	0.162526	0.046*
C4	1.2385 (17)	0.0077 (18)	0.3947 (13)	0.035 (3)
H4A	1.126049	−0.037376	0.327911	0.042*
H4B	1.284935	−0.075140	0.427765	0.042*
C5	1.206 (2)	0.1374 (18)	0.5023 (14)	0.039 (2)
H5A	1.319763	0.181893	0.567821	0.047*
H5B	1.127970	0.092387	0.541897	0.047*
C6	0.8751 (19)	0.2106 (18)	0.3709 (14)	0.039 (2)
H6A	0.868179	0.113955	0.301594	0.047*
H6B	0.817806	0.185297	0.431304	0.047*
C7	0.7789 (16)	0.3263 (16)	0.3162 (12)	0.030 (2)
H7A	0.864140	0.420800	0.338968	0.036*
H7B	0.686666	0.355435	0.359299	0.036*
C8	0.8623 (16)	0.2892 (16)	0.0814 (13)	0.030 (2)
H8A	0.824277	0.329504	0.008985	0.036*
H8B	0.956964	0.366690	0.147795	0.036*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
I1	0.0407 (5)	0.0292 (6)	0.0494 (6)	0.0003 (4)	0.0136 (4)	0.0134 (4)
I2	0.0437 (5)	0.0156 (5)	0.0585 (6)	0.0031 (4)	0.0271 (4)	0.0110 (4)
Cu1	0.0348 (8)	0.0176 (10)	0.0487 (10)	0.0019 (7)	0.0144 (7)	0.0110 (7)
Cu2	0.0424 (10)	0.0387 (12)	0.0546 (12)	0.0177 (8)	0.0220 (8)	0.0219 (9)
S1	0.0277 (15)	0.030 (2)	0.0386 (18)	0.0065 (13)	0.0051 (13)	0.0109 (15)
S2	0.0374 (17)	0.025 (2)	0.042 (2)	0.0028 (14)	0.0146 (14)	0.0084 (15)
S3	0.0284 (15)	0.0216 (19)	0.045 (2)	0.0109 (13)	0.0161 (14)	0.0138 (14)
N1	0.025 (5)	0.013 (6)	0.042 (6)	0.005 (4)	0.017 (5)	0.009 (4)
C1	0.029 (4)	0.014 (5)	0.031 (5)	0.007 (3)	0.011 (4)	0.009 (3)
C2	0.029 (4)	0.014 (5)	0.031 (5)	0.007 (3)	0.011 (4)	0.009 (3)
C3	0.052 (8)	0.022 (8)	0.038 (8)	0.021 (6)	0.014 (6)	0.002 (6)
C4	0.030 (6)	0.038 (9)	0.046 (8)	0.005 (6)	0.012 (6)	0.028 (7)
C5	0.050 (6)	0.027 (6)	0.044 (6)	0.005 (5)	0.012 (5)	0.018 (5)
C6	0.050 (6)	0.027 (6)	0.044 (6)	0.005 (5)	0.012 (5)	0.018 (5)
C7	0.029 (5)	0.024 (6)	0.042 (5)	0.013 (4)	0.018 (4)	0.011 (4)
C8	0.029 (5)	0.024 (6)	0.042 (5)	0.013 (4)	0.018 (4)	0.011 (4)

Geometric parameters (Å, º) top

Cu1—N1	2.095 (10)	C1—C2ⁱⁱⁱ	1.373 (17)
Cu1—S1	2.342 (4)	C1—C8	1.511 (18)
Cu1—S2	2.331 (4)	C2—C3	1.504 (19)
Cu1—I2ⁱ	2.5193 (18)	C3—H3A	0.9700
Cu2—S3	2.359 (4)	C3—H3B	0.9700
Cu2—I1	2.665 (2)	C4—C5	1.50 (2)
Cu2—I2	2.6166 (19)	C4—H4A	0.9700
I1—Cu2ⁱⁱ	2.675 (2)	C4—H4B	0.9700
Cu2—Cu2ⁱⁱ	2.663 (4)	C5—H5A	0.9700
S1—C3	1.803 (13)	C5—H5B	0.9700
S1—C4	1.834 (13)	C6—C7	1.50 (2)
S2—C5	1.779 (16)	C6—H6A	0.9700
S2—C6	1.808 (14)	C6—H6B	0.9700
S3—C7	1.793 (13)	C7—H7A	0.9700
S3—C8	1.803 (12)	C7—H7B	0.9700
N1—C1	1.346 (16)	C8—H8A	0.9700
N1—C2	1.364 (16)	C8—H8B	0.9700

N1—Cu1—S2	110.2 (3)	C2—C3—S1	116.7 (10)
N1—Cu1—S1	85.3 (3)	C2—C3—H3A	108.1
S2—Cu1—S1	91.74 (14)	S1—C3—H3A	108.1
N1—Cu1—I2ⁱ	121.1 (3)	C2—C3—H3B	108.1
S2—Cu1—I2ⁱ	112.48 (12)	S1—C3—H3B	108.1
S1—Cu1—I2ⁱ	130.61 (10)	H3A—C3—H3B	107.3
S3—Cu2—I2	109.54 (11)	C5—C4—S1	110.1 (10)
S3—Cu2—I1	105.86 (10)	C5—C4—H4A	109.6
I2—Cu2—I1	109.04 (8)	S1—C4—H4A	109.6
S3—Cu2—I1ⁱⁱ	99.22 (11)	C5—C4—H4B	109.6
I2—Cu2—I1ⁱⁱ	112.01 (7)	S1—C4—H4B	109.6
I1—Cu2—I1ⁱⁱ	120.18 (7)	H4A—C4—H4B	108.2
Cu2—I1—Cu2ⁱⁱ	59.82 (7)	C4—C5—S2	114.4 (10)
Cu1^iv—I2—Cu2	94.93 (7)	C4—C5—H5A	108.7
Cu2ⁱⁱ—Cu2—I1	60.27 (7)	S2—C5—H5A	108.7
Cu2ⁱⁱ—Cu2—I1ⁱⁱ	59.91 (7)	C4—C5—H5B	108.7
S3—Cu2—Cu2ⁱⁱ	115.75 (13)	S2—C5—H5B	108.7
I2—Cu2—Cu2ⁱⁱ	134.68 (11)	H5A—C5—H5B	107.6
C3—S1—C4	100.9 (7)	C7—C6—S2	110.2 (10)
C3—S1—Cu1	96.4 (5)	C7—C6—H6A	109.6
C4—S1—Cu1	94.5 (5)	S2—C6—H6A	109.6
C5—S2—C6	104.7 (7)	C7—C6—H6B	109.6
C5—S2—Cu1	98.8 (5)	S2—C6—H6B	109.6
C6—S2—Cu1	105.0 (5)	H6A—C6—H6B	108.1
C7—S3—C8	102.8 (6)	C6—C7—S3	117.8 (10)
C7—S3—Cu2	106.0 (4)	C6—C7—H7A	107.9
C8—S3—Cu2	105.2 (5)	S3—C7—H7A	107.9
C1—N1—C2	116.6 (10)	C6—C7—H7B	107.9
C1—N1—Cu1	124.9 (9)	S3—C7—H7B	107.9
C2—N1—Cu1	118.5 (8)	H7A—C7—H7B	107.2
N1—C1—C2ⁱⁱⁱ	122.1 (12)	C1—C8—S3	113.2 (9)
N1—C1—C8	117.1 (11)	C1—C8—H8A	108.9
C2ⁱⁱⁱ—C1—C8	120.8 (11)	S3—C8—H8A	108.9
N1—C2—C1ⁱⁱⁱ	121.3 (11)	C1—C8—H8B	108.9
N1—C2—C3	117.9 (11)	S3—C8—H8B	108.9
C1ⁱⁱⁱ—C2—C3	120.7 (12)	H8A—C8—H8B	107.7

C2—N1—C1—C2ⁱⁱⁱ	0.0 (19)	Cu1—S1—C4—C5	−52.9 (10)
Cu1—N1—C1—C2ⁱⁱⁱ	179.6 (9)	S1—C4—C5—S2	62.8 (12)
C2—N1—C1—C8	177.4 (10)	C6—S2—C5—C4	74.9 (11)
Cu1—N1—C1—C8	−3.0 (15)	Cu1—S2—C5—C4	−33.3 (10)
C1—N1—C2—C1ⁱⁱⁱ	0.0 (19)	C5—S2—C6—C7	−176.2 (10)
Cu1—N1—C2—C1ⁱⁱⁱ	−179.6 (9)	Cu1—S2—C6—C7	−72.6 (10)
C1—N1—C2—C3	179.3 (11)	S2—C6—C7—S3	121.3 (9)
Cu1—N1—C2—C3	−0.3 (15)	C8—S3—C7—C6	−78.8 (11)
N1—C2—C3—S1	18.3 (17)	Cu2—S3—C7—C6	171.0 (9)
C1ⁱⁱⁱ—C2—C3—S1	−162.3 (10)	N1—C1—C8—S3	−103.2 (11)
C4—S1—C3—C2	72.6 (13)	C2ⁱⁱⁱ—C1—C8—S3	74.2 (14)
Cu1—S1—C3—C2	−23.2 (12)	C7—S3—C8—C1	96.8 (10)
C3—S1—C4—C5	−150.3 (10)	Cu2—S3—C8—C1	−152.4 (8)

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

Acknowledgements

HSE is grateful to the University of Neuchâtel for their support over the years.

Funding information

Funding for this research was provided by: Swiss National Science Foundation and the University of Neuchâtel .

References

Addison, A. W., Rao, T. N., Reedijk, J., van Rijn, J. & Verschoor, G. C. (1984). J. Chem. Soc. Dalton Trans. pp. 1349–1356. CSD CrossRef Web of Science Google Scholar
Assoumatine, T. (1999). PhD Thesis, University of Neuchâtel, Switzerland. Google Scholar
Assoumatine, T. & Stoeckli-Evans, H. (2020a). Acta Cryst. E76, 977–983. CrossRef IUCr Journals Google Scholar
Assoumatine, T. & Stoeckli-Evans, H. (2020b). IUCrData, 5, x200467. Google Scholar
Assoumatine, T. & Stoeckli-Evans, H. (2020c). IUCrData, 5, x200401. Google Scholar
Assoumatine, T. & Stoeckli-Evans, H. (2020d). Acta Cryst. E76, 539–546. Web of Science CSD CrossRef IUCr Journals Google Scholar
Casabo, J., Flor, T., Hill, M. N. S., Jenkins, H. A., Lockhart, J. C., Loeb, S. J., Romero, I. & Teixidor, F. (1995). Inorg. Chem. 34, 5410–5415. CSD CrossRef CAS Web of Science Google Scholar
Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171–179. Web of Science CrossRef IUCr Journals Google Scholar
Groot, B. de, Hanan, G. S. & Loeb, S. J. (1991). Inorg. Chem. 30, 4644–4647. Google Scholar
Groot, B. de & Loeb, S. J. (1990). Inorg. Chem. 29, 4084–4090. Google Scholar
Linden, A. (2020). Acta Cryst. E76, 765–775. Web of Science CrossRef IUCr Journals Google Scholar
Macrae, C. F., Sovago, I., Cottrell, S. J., Galek, P. T. A., McCabe, P., Pidcock, E., Platings, M., Shields, G. P., Stevens, J. S., Towler, M. & Wood, P. A. (2020). J. Appl. Cryst. 53, 226–235. Web of Science CrossRef CAS IUCr Journals Google Scholar
Masci, B. & Thuéry, P. (2008). Cryst. Growth Des. 8, 1689–1696. Web of Science CSD CrossRef CAS Google Scholar
Nawrot, I., Machura, B. & Kruszynski, R. (2015). CrystEngComm, 17, 830–845. Web of Science CSD CrossRef CAS Google Scholar
Ouellette, W., Burkholder, E., Manzar, S., Bewley, L., Rarig, R. S. & Zubieta, J. (2004). Solid State Sci. 6, 77–84. Web of Science CSD CrossRef CAS Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Sheldrick, G. M. (2015). Acta Cryst. C71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Spek, A. L. (2020). Acta Cryst. E76, 1–11. Web of Science CrossRef IUCr Journals Google Scholar
Stoe & Cie (1997). IPDS-I Bedienungshandbuch. Stoe & Cie GmbH, Darmstadt, Germany. Google Scholar
Wang, T., Huang, K., Peng, M., Li, X., Han, D., Jing, L. & Qin, D. (2019). CrystEngComm, 21, 494–501. Web of Science CSD CrossRef CAS Google Scholar
Westrip, S. P. (2010). J. Appl. Cryst. 43, 920–925. Web of Science CrossRef CAS IUCr Journals Google Scholar
Yang, L., Powell, D. R. & Houser, R. P. (2007). Dalton Trans. pp. 955–964. Web of Science CSD CrossRef PubMed CAS Google Scholar
Zhang, F., Yan, P., Li, H., Zou, X., Hou, G. & Li, G. (2014). Dalton Trans. 43, 12574–12581. Web of Science CSD CrossRef CAS PubMed Google Scholar

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