supplementary materials


tk5229 scheme

Acta Cryst. (2013). E69, m351-m352    [ doi:10.1107/S1600536813014578 ]

Bis[[mu]-2,5-bis(pyridin-2-yl)-1,3,4-thiadiazole-[kappa]4N2,N3:N4,N5]bis[(nitrato-[kappa]O)silver(I)] tetrahydrate

A. Laachir, F. Bentiss, S. Guesmi, M. Saadi and L. El Ammari

Abstract top

The self-assembly of an angular 2,5-bis(pyridin-2-yl)-1,3,4-thiadiazole ligand (L) with silver nitrate (AgNO3) produced a new dinuclear silver(I) coordination complex, [Ag2(C12H8N4S)2(NO3)2]·4H2O, which crystallizes with two Ag atoms bridged by two L ligands. The Ag atom is surrounded by four N atoms of L and by one O from the nitrate anion defining a distorted square pyramid. The atoms comprising the dication are nearly coplanar, with an r.m.s. deviation of 0.1997 Å. Molecules are linked by C-H...O and O-H...O hydrogen bonds through nitrate anions and water molecules, forming a two-dimensional porous network. The overall structure involves stacking of Ag complex layers along the b axis. The cohesion in the three-dimensional architecture is ensured by O...Ag interactions.

Comment top

The design and construction of novel coordination polymers are very important parts of crystal engineering not only for the purpose of generating functional materials (Maspoch et al., 2004) but also for their fascinating structures (Brammer, 2004). So far, the design and synthesis of new ligands with various coordinating modes, the exploration of synthetic methods to construct coordination polymers, and investigation on the effect of various factors upon architectures have greatly contributed to this field (Ghosh et al., 2004). The compound 2,5-bis(2-pyridyl)-1,3,4-thiadiazole was usually used as a bidentate ligand to form five-atom ring complexes and sometimes it coordinates two metal atoms by four nitrogen atoms as double-bidentate ligand. The structures of monomeric complexes of the neutral 2,5-bis(2-pyridyl)-1,3,4-thiadiazole derivative with Cu2+ (nitrate, perchlorate and trifluoromethanesulfonate) and Ag+ (SbF6-) have been previously reported (Bentiss et al., 2012; Niu et al., 2009). Recently, the study of the new di-nuclear silver(I) coordination complexes with 2,5-bis(2-pyridyl)-1,3,4-thiadiazole showed that the supramolecular structures of its silver complexes can change with the size of counter-anions of the same polyhedron (Niu et al., 2009). As a continuation of our work, in this contribution, we report here the synthesis and the single-crystal structure determination of the new dimeric complex formed by 2,5-bis(2-pyridyl)-1,3,4-thiadiazole (L) with silver nitrate as counter ions.

The asymmetric unit of the title compound, [2,5-bis(2-pyridyl)-1,3,4- thiadiazole]silver(I) nitrate, dihydrate is doubled by the application of a centre of inversion, resulting in a Ag2-containing dimeric complex. The structure shows the silver cation in a distorted square pyramid site formed by four nitrogen atoms belonging to one organic ligand and an O atom of a nitrate anion (Fig. 1). Each ligand molecule is build up by two six-membered rings linked through a five-membered ring. The two silver atoms and ligands are nearly coplanar, with a r.m.s. deviation of 0.1997 Å. The molecules are linked together by C–H···O and O–H···O hydrogen bonds through nitrate and water molecules, forming a two-dimensional porous network. The overall structure involves stacking of Ag complex layers nearly along the b axis. The cohesion in the crystal is ensured by O3–Ag1 interaction (Fig. 2 and Table 2).

Related literature top

For the synthesis of the ligand, see: Lebrini et al. (2005). For background to coordination polymers, see: Brammer (2004); Ghosh et al. (2004); Maspoch et al. (2004). For complexes with the same ligand but with other metals and counter-anions, see: Bentiss et al., (2012); Niu et al. (2009).

Experimental top

2,5-Bis(2-pyridyl)-1,3,4-thiadiazole ligand (L) was synthesized as described previously by Lebrini et al. (2005). AgNO3 (0.75 mmol, 0.13 g) in water (5 ml ) was added to L (0.21 mmol, 50 mg) dissolved in ethanol (13 ml). The resulting solution was stirred for 30 min. The solution was filtered and allowed to stand at ambient temperature. After seven days, yellow blocks crystallized. Crystals were washed with water and dried under vacuum (yield 34%). These crystals were used as isolated for single-crystal X-ray analysis. Anal. Calc. for C24H24Ag2N10O10S2. C, 37.60; H, 3.13; N, 18.28 S, 8.37; Found: C, 37.69; H, 3.17; N, 18.21; S, 8.34.

Refinement top

H atoms were located in a difference map and treated as riding with C—H = 0.93 Å (aromatic) and O—H = 0.86 Å (water) with Uiso(H) = 1.2 Ueq(aromatic) and Uiso(H) = 1.5 Ueq (water). The reflections (001), (01–1), (0–11) and (010) are removed from the refinement because they are affected by the beam stop.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: APEX2 (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2008); software used to prepare material for publication: PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. Plot of the crystal structure showing the molecules linked to the silver cation, with the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. Symmetry code: (i) -x + 1, -y, -z; (ii) -x, -y, -z + 1; (iii) -x + 1, -y + 1, -z + 1.
[Figure 2] Fig. 2. Partial plot of the unit cell showing crystal packing. Hydrogen bonds are depicted as dashed lines. Symmetry codes: (c) -x, -y, -z + 1; (e) -x + 1, -y + 1, -z + 1; (h) -x, -y, -z.
Bis[µ-2,5-bis(pyridin-2-yl)-1,3,4-thiadiazole-κ4N2,N3:N4,N5]bis[(nitrato-κO)silver(I)] tetrahydrate top
Crystal data top
[Ag2(C12H8N4S)2(NO3)2]·4H2OZ = 1
Mr = 892.41F(000) = 444
Triclinic, P1Dx = 1.906 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 5.4251 (1) ÅCell parameters from 29938 reflections
b = 10.6894 (3) Åθ = 2.9–32.0°
c = 14.5865 (3) ŵ = 1.47 mm1
α = 108.910 (1)°T = 296 K
β = 91.447 (1)°Block, colourless
γ = 102.440 (1)°0.42 × 0.32 × 0.23 mm
V = 777.30 (3) Å3
Data collection top
Bruker X8 APEX
diffractometer
5388 independent reflections
Radiation source: fine-focus sealed tube3919 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.029
φ and ω scansθmax = 32.0°, θmin = 2.9°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2008)
h = 88
Tmin = 0.739, Tmax = 0.867k = 1515
29938 measured reflectionsl = 2021
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.034Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.090H-atom parameters constrained
S = 1.01 w = 1/[σ2(Fo2) + (0.0369P)2 + 0.5008P]
where P = (Fo2 + 2Fc2)/3
5388 reflections(Δ/σ)max < 0.001
217 parametersΔρmax = 0.92 e Å3
0 restraintsΔρmin = 0.93 e Å3
Crystal data top
[Ag2(C12H8N4S)2(NO3)2]·4H2Oγ = 102.440 (1)°
Mr = 892.41V = 777.30 (3) Å3
Triclinic, P1Z = 1
a = 5.4251 (1) ÅMo Kα radiation
b = 10.6894 (3) ŵ = 1.47 mm1
c = 14.5865 (3) ÅT = 296 K
α = 108.910 (1)°0.42 × 0.32 × 0.23 mm
β = 91.447 (1)°
Data collection top
Bruker X8 APEX
diffractometer
5388 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2008)
3919 reflections with I > 2σ(I)
Tmin = 0.739, Tmax = 0.867Rint = 0.029
29938 measured reflectionsθmax = 32.0°
Refinement top
R[F2 > 2σ(F2)] = 0.034H-atom parameters constrained
wR(F2) = 0.090Δρmax = 0.92 e Å3
S = 1.01Δρmin = 0.93 e Å3
5388 reflectionsAbsolute structure: ?
217 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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
xyzUiso*/Ueq
Ag10.88258 (4)0.17155 (2)0.082506 (13)0.05506 (8)
S10.27700 (10)0.00777 (6)0.27138 (4)0.03914 (12)
N10.9412 (3)0.2260 (2)0.25072 (14)0.0399 (4)
N20.5007 (4)0.0657 (2)0.13988 (14)0.0442 (4)
N30.2802 (4)0.0253 (2)0.09364 (14)0.0435 (4)
N40.1644 (4)0.2195 (2)0.02161 (14)0.0415 (4)
C11.1468 (4)0.3134 (3)0.30566 (19)0.0473 (5)
H11.27960.34770.27490.057*
C21.1710 (5)0.3552 (3)0.4058 (2)0.0568 (7)
H21.31890.41510.44140.068*
C30.9763 (6)0.3080 (3)0.4524 (2)0.0606 (7)
H30.98940.33500.52010.073*
C40.7590 (5)0.2191 (3)0.39710 (17)0.0491 (6)
H40.62210.18630.42680.059*
C50.7497 (4)0.1801 (2)0.29698 (16)0.0367 (4)
C60.5261 (4)0.0856 (2)0.23297 (15)0.0358 (4)
C70.1435 (4)0.0725 (2)0.15227 (15)0.0349 (4)
C80.1038 (4)0.1714 (2)0.11867 (15)0.0345 (4)
C90.2607 (4)0.2091 (3)0.18250 (17)0.0428 (5)
H90.21140.17480.24920.051*
C100.4937 (5)0.2991 (3)0.1457 (2)0.0476 (5)
H100.60270.32730.18710.057*
C110.5609 (5)0.3460 (3)0.0472 (2)0.0477 (5)
H110.71860.40420.02100.057*
C120.3919 (5)0.3058 (3)0.01236 (18)0.0476 (5)
H120.43740.34000.07930.057*
O11.0220 (4)0.6251 (2)0.29332 (16)0.0703 (6)
O20.6832 (4)0.4674 (3)0.2406 (2)0.0785 (7)
O30.9959 (4)0.4677 (2)0.15475 (16)0.0695 (6)
N50.9004 (4)0.5189 (2)0.22918 (16)0.0474 (5)
O40.2764 (8)0.0495 (3)0.5333 (3)0.1395 (14)
H4A0.15110.08320.55590.209*
H4B0.40790.11630.55420.209*
O50.4863 (4)0.3278 (2)0.61006 (16)0.0730 (6)
H5A0.40200.37690.64970.109*
H5B0.63290.34530.64150.109*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Ag10.05582 (12)0.06872 (16)0.03379 (10)0.00435 (9)0.01077 (7)0.01998 (9)
S10.0410 (3)0.0453 (3)0.0288 (2)0.0034 (2)0.00920 (19)0.0134 (2)
N10.0394 (9)0.0424 (11)0.0376 (10)0.0057 (8)0.0089 (7)0.0152 (8)
N20.0441 (10)0.0516 (12)0.0328 (9)0.0017 (8)0.0057 (7)0.0170 (9)
N30.0451 (10)0.0500 (12)0.0312 (9)0.0005 (8)0.0055 (7)0.0153 (8)
N40.0433 (9)0.0430 (11)0.0335 (9)0.0051 (8)0.0079 (7)0.0096 (8)
C10.0407 (11)0.0489 (14)0.0491 (13)0.0011 (10)0.0063 (10)0.0185 (11)
C20.0464 (13)0.0549 (16)0.0543 (15)0.0029 (11)0.0047 (11)0.0091 (13)
C30.0604 (16)0.073 (2)0.0359 (13)0.0036 (14)0.0014 (11)0.0101 (13)
C40.0462 (12)0.0605 (16)0.0370 (12)0.0039 (11)0.0085 (9)0.0168 (11)
C50.0377 (10)0.0376 (11)0.0352 (10)0.0076 (8)0.0075 (8)0.0135 (9)
C60.0377 (10)0.0381 (11)0.0335 (10)0.0077 (8)0.0104 (8)0.0151 (9)
C70.0390 (10)0.0364 (11)0.0296 (9)0.0094 (8)0.0078 (7)0.0110 (8)
C80.0378 (9)0.0330 (11)0.0331 (10)0.0098 (8)0.0078 (8)0.0105 (8)
C90.0442 (11)0.0481 (14)0.0375 (11)0.0081 (10)0.0116 (9)0.0176 (10)
C100.0427 (11)0.0496 (14)0.0540 (14)0.0082 (10)0.0157 (10)0.0232 (12)
C110.0405 (11)0.0409 (13)0.0555 (15)0.0031 (9)0.0061 (10)0.0124 (11)
C120.0474 (12)0.0468 (14)0.0387 (12)0.0017 (10)0.0030 (9)0.0076 (10)
O10.0593 (12)0.0748 (15)0.0585 (12)0.0083 (10)0.0056 (10)0.0037 (11)
O20.0413 (10)0.0866 (16)0.1001 (18)0.0029 (10)0.0200 (11)0.0283 (14)
O30.0732 (13)0.0715 (14)0.0570 (12)0.0109 (11)0.0245 (10)0.0152 (11)
N50.0367 (9)0.0564 (13)0.0502 (12)0.0083 (9)0.0025 (8)0.0211 (10)
O40.169 (4)0.077 (2)0.154 (4)0.004 (2)0.004 (3)0.037 (2)
O50.0582 (11)0.0823 (16)0.0599 (13)0.0109 (11)0.0061 (10)0.0029 (11)
Geometric parameters (Å, º) top
Ag1—N4i2.2785 (19)C3—H30.9300
Ag1—N12.3273 (19)C4—C51.379 (3)
Ag1—N22.4421 (19)C4—H40.9300
Ag1—N3i2.5519 (19)C5—C61.472 (3)
Ag1—O32.911 (2)C7—C81.476 (3)
S1—C61.719 (2)C8—C91.374 (3)
S1—C71.721 (2)C9—C101.386 (3)
N1—C11.334 (3)C9—H90.9300
N1—C51.343 (3)C10—C111.369 (4)
N2—C61.303 (3)C10—H100.9300
N2—N31.365 (3)C11—C121.376 (4)
N3—C71.299 (3)C11—H110.9300
N3—Ag1i2.5519 (19)C12—H120.9300
N4—C121.342 (3)O1—N51.247 (3)
N4—C81.345 (3)O2—N51.229 (3)
N4—Ag1i2.2785 (19)O3—N51.230 (3)
C1—C21.376 (4)O4—H4A0.8601
C1—H10.9300O4—H4B0.8601
C2—C31.365 (4)O5—H5A0.8601
C2—H20.9300O5—H5B0.8600
C3—C41.384 (4)
N4i—Ag1—N1129.5 (1)C5—C4—H4120.7
N4i—Ag1—N2159.9 (1)C3—C4—H4120.7
N1—Ag1—N270.1 (1)N1—C5—C4122.9 (2)
N4i—Ag1—N3i69.0 (1)N1—C5—C6115.1 (2)
N1—Ag1—N3i157.2 (1)C4—C5—C6122.0 (2)
N2—Ag1—N3i90.9 (1)N2—C6—C5121.8 (2)
N4i—Ag1—O379.4 (1)N2—C6—S1113.6 (2)
N1—Ag1—O376.6 (1)C5—C6—S1124.6 (2)
N2—Ag1—O3113.6 (1)N3—C7—C8122.4 (2)
N3i—Ag1—O3124.0 (1)N3—C7—S1113.7 (2)
C6—S1—C787.2 (1)C8—C7—S1123.9 (2)
C1—N1—C5117.4 (2)N4—C8—C9123.0 (2)
C1—N1—Ag1123.0 (2)N4—C8—C7114.9 (2)
C5—N1—Ag1119.2 (2)C9—C8—C7122.1 (2)
C6—N2—N3112.7 (2)C8—C9—C10118.7 (2)
C6—N2—Ag1113.1 (2)C8—C9—H9120.6
N3—N2—Ag1133.5 (2)C10—C9—H9120.6
C7—N3—N2112.8 (2)C11—C10—C9118.9 (2)
C7—N3—Ag1i109.7 (2)C11—C10—H10120.5
N2—N3—Ag1i135.3 (2)C9—C10—H10120.5
C12—N4—C8117.2 (2)C10—C11—C12119.1 (2)
C12—N4—Ag1i120.8 (2)C10—C11—H11120.5
C8—N4—Ag1i121.8 (2)C12—C11—H11120.5
N1—C1—C2123.0 (2)N4—C12—C11123.0 (2)
N1—C1—H1118.5N4—C12—H12118.5
C2—C1—H1118.5C11—C12—H12118.5
C3—C2—C1119.4 (2)N5—O3—Ag1115.4 (2)
C3—C2—H2120.3O2—N5—O3120.5 (2)
C1—C2—H2120.3O2—N5—O1119.2 (2)
C2—C3—C4118.7 (3)O3—N5—O1120.3 (2)
C2—C3—H3120.6H4A—O4—H4B104.9
C4—C3—H3120.6H5A—O5—H5B104.9
C5—C4—C3118.6 (2)
N4i—Ag1—N1—C111.5 (2)Ag1—N2—C6—S1171.2 (1)
N2—Ag1—N1—C1173.9 (2)N1—C5—C6—N210.6 (3)
N3i—Ag1—N1—C1150.9 (2)C4—C5—C6—N2168.9 (2)
O3—Ag1—N1—C152.4 (2)N1—C5—C6—S1169.5 (2)
N4i—Ag1—N1—C5176.3 (2)C4—C5—C6—S111.0 (3)
N2—Ag1—N1—C51.7 (2)C7—S1—C6—N20.1 (2)
N3i—Ag1—N1—C536.8 (3)C7—S1—C6—C5179.8 (2)
O3—Ag1—N1—C5119.8 (2)N2—N3—C7—C8179.5 (2)
N4i—Ag1—N2—C6164.0 (2)Ag1i—N3—C7—C814.6 (3)
N1—Ag1—N2—C63.8 (2)N2—N3—C7—S10.0 (3)
N3i—Ag1—N2—C6163.3 (2)Ag1i—N3—C7—S1165.9 (1)
O3—Ag1—N2—C668.5 (2)C6—S1—C7—N30.1 (2)
N4i—Ag1—N2—N34.9 (4)C6—S1—C7—C8179.5 (2)
N1—Ag1—N2—N3172.7 (2)C12—N4—C8—C91.4 (3)
N3i—Ag1—N2—N35.6 (3)Ag1i—N4—C8—C9173.6 (2)
O3—Ag1—N2—N3122.5 (2)C12—N4—C8—C7177.5 (2)
C6—N2—N3—C70.0 (3)Ag1i—N4—C8—C77.5 (3)
Ag1—N2—N3—C7168.9 (2)N3—C7—C8—N46.5 (3)
C6—N2—N3—Ag1i161.0 (2)S1—C7—C8—N4174.0 (2)
Ag1—N2—N3—Ag1i8.0 (4)N3—C7—C8—C9172.4 (2)
C5—N1—C1—C21.4 (4)S1—C7—C8—C97.1 (3)
Ag1—N1—C1—C2173.8 (2)N4—C8—C9—C101.0 (4)
N1—C1—C2—C31.2 (4)C7—C8—C9—C10177.9 (2)
C1—C2—C3—C40.1 (5)C8—C9—C10—C110.9 (4)
C2—C3—C4—C51.0 (5)C9—C10—C11—C122.1 (4)
C1—N1—C5—C40.4 (3)C8—N4—C12—C110.1 (4)
Ag1—N1—C5—C4173.1 (2)Ag1i—N4—C12—C11175.0 (2)
C1—N1—C5—C6179.1 (2)C10—C11—C12—N41.7 (4)
Ag1—N1—C5—C66.4 (3)N4i—Ag1—O3—N5174.6 (2)
C3—C4—C5—N10.8 (4)N1—Ag1—O3—N539.4 (2)
C3—C4—C5—C6179.8 (2)N2—Ag1—O3—N521.6 (2)
N3—N2—C6—C5179.8 (2)N3i—Ag1—O3—N5129.9 (2)
Ag1—N2—C6—C58.9 (3)Ag1—O3—N5—O239.5 (3)
N3—N2—C6—S10.1 (3)Ag1—O3—N5—O1141.5 (2)
Symmetry code: (i) x+1, y, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O4—H4B···O50.862.082.777 (4)138
O4—H4A···O4ii0.862.512.980 (9)115
C1—H1···O2iii0.932.443.342 (3)164
C12—H12···O2iv0.932.483.376 (4)162
O5—H5A···O2v0.862.052.874 (3)162
O5—H5A···O1v0.862.463.191 (3)143
O5—H5B···O1vi0.861.992.851 (3)176
Symmetry codes: (ii) x, y, z+1; (iii) x+1, y, z; (iv) x, y, z; (v) x+1, y+1, z+1; (vi) x+2, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O4—H4B···O50.862.082.777 (4)138
O4—H4A···O4i0.862.512.980 (9)115
C1—H1···O2ii0.932.443.342 (3)164
C12—H12···O2iii0.932.483.376 (4)162
O5—H5A···O2iv0.862.052.874 (3)162
O5—H5A···O1iv0.862.463.191 (3)143
O5—H5B···O1v0.861.992.851 (3)176
Symmetry codes: (i) x, y, z+1; (ii) x+1, y, z; (iii) x, y, z; (iv) x+1, y+1, z+1; (v) x+2, y+1, z+1.
Acknowledgements top

The authors thank the Unit of Support for Technical and Scientific Research (UATRS, CNRST) for the X-ray measurements.

references
References top

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