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The crystal structure of a third polymorphic form of the known 4-(2,6-difluoro­phenyl)-1,2,3,5-dithia­diazolyl radical, C7H3F2N2S2, is reported. This new polymorph represents a unique crystal-packing motif never before observed for 1,2,3,5-dithia­diazolyl (DTDA) radicals. In the two known polymorphic forms of the title compound, all of the mol­ecules form cis-cofacial dimers, such that two mol­ecules are π-stacked with like atoms one on top of the other, a common arrangement for DTDA species. By contrast, the third polymorph, reported herein, contains two crystallographically unique mol­ecules organized such that only 50% are dimerized, while the other 50% remain monomeric radicals. The dimerized mol­ecules are arranged in the trans-antarafacial mode. This less common dimer motif for DTDA species is characterized by π–π inter­actions between the S atoms [S...S = 3.208 (1) Å at 110 K], such that the two mol­ecules of the dimer are related by a centre of inversion. The most remarkable aspect of this third polymorph is that the DTDA dimers are co-packed with monomers. The monomeric radicals are arranged in one-dimensional chains directed by close lateral inter­molecular contacts between the two S atoms of one DTDA heterocycle and an N atom of a neighbouring coplanar DTDA heterocycle [S...N = 2.857 (2) and 3.147 (2) Å at 110 K].

Supporting information


Crystallographic Information File (CIF)
Contains datablocks global, I


Structure factor file (CIF format)
Contains datablock I

CCDC reference: 779965

Comment top

Stable thiazyl radicals continue to be studied, due to interest in their conductivity (Leitch et al., 2009), bistability (Brusso et al., 2004) and magnetic properties (Robertson et al., 2007) in the solid state. These properties are all a function of the intermolecular interactions, and so crystal packing remains at the forefront of research in this field. Fluorinated aryl substituents of 1,2,3,5-dithiadiazolyl (DTDA) radicals have been of particular interest since the discovery of spin-canted antiferromagnetism below ca 36 K in the β-phase of 4-(4'-cyano-tetrafluorophenyl)-DTDA (Banister et al., 1996). A series of difluorophenyl-DTDA radicals was reported by the same group, including the title compound, (I), 4-(2',6'-difluorophenyl)-DTDA (Banister et al., 1997). That preliminary report documented the formation of cis-cofacial dimers of (I) in the solid state in the monoclinic α form, (Ia). This is the same dimerization mode that is observed for the parent 4-phenyl-1,2,3,5-dithiadiazolyl radical [Vegas et al., 1980; Cambridge Structural Database (Allen, 2002) refcode PHTHAZ]. The crystallographic data for (Ia) were published very recently, along with data for a second polymorph, the tetragonal β form, (Ib) (Clarke et al., 2010). The cis-cofacial dimers of (I) persist in (Ib). We have now reinvestigated (I) and discovered a third polymorphic form, the monoclinic γ form, (Ic), which is unique among known DTDA species, and we report its crystal structure here.

The two crystallographically unique molecules of (Ic) (Molecules 1 and 2) are shown in Fig. 1. Polymorph (Ic) crystallizes as dark-purple blocks under static vacuum sublimation at 354 K and ca 10−3 Torr (1 Torr = 133.322 Pa). It is worth noting that (Ic) has a similar habit to that of (Ia), and that we have recovered crystals of both (Ia) and (Ib) under similar sublimation conditions used to grow crystals of (Ic). Given that both (Ia) and (Ic) are monoclinic, and that our data for (Ic) were collected at a lower temperature than those reported in the literature for (Ia), we have collected unit-cell data for (Ia) at both 150 and 110 K, verifying that it is not a high-temperature phase of (Ic).

Polymorph (Ic) shows a unique molecular arrangement for DTDA compounds. Only 50% of the molecules are dimerized (Molecule 2). The trans-antarafacial ππ dimers present in (Ic), shown in Fig. 2, exhibit intermolecular S···S contacts (Table 1) that are slightly longer than the typical range of 2.9–3.1 Å for this dimerization mode (Cordes et al., 1992). The two molecules of a dimer are related by a centre of inversion, so the mean angle between the planes of the DTDA rings is necessarily zero. The mean distance between planes is 2.918 (2) Å, which is significantly less than the distance between planes in graphite (Nelson & Riley, 1945) and is in keeping with the prevailing consensus that these dimers provide an example of four-centred two-electron bonding (Harcourt, 1991).

Interestingly, an intermolecular antara-cofacial ππ stacking of the aryl rings assists in the co-packing of the dimers in (Ic) along [110], shown in Fig. 3(a); the distance between the mean planes of the aryl rings is 3.392 (4) Å. The formation of ππ dimers via close intermolecular S···S contacts is a common feature in crystal structures of DTDA radicals and is known to occur in a variety of geometries (Rawson et al., 1995), including those observed in all three polymorphs of (I).

The remaining molecules (50%) in polymorph (Ic) remain as monomeric radicals (Molecule 1) and are organized in linear arrays, or one-dimensional chains propagating along [010], such that the DTDA rings of neighbouring molecules are roughly coplanar [angle of 1.21 (14)° between the mean planes of neighbouring DTDA rings], as shown in Fig. 3(b). Intermolecular electrostatic Sδ+···Nδ interactions create close lateral contacts that direct this packing arrangement (Table 1). This also results in relatively close lateral S···S contacts (Table 1). These one-dimensional chains of neutral radicals are isolated from one another by linear arrays of the dimers. A segment of the crystal structure illustrating this relationship is shown from two different perspectives in Fig. 4. The most significant contact directing the co-packing of the dimers with the one-dimensional chains of monomers appears to be the close intermolecular Sδ+···Fδ distances between an F atom of Molecule 1 and the two S atoms of a neighbouring Molecule 2 (Table 1). This interaction is expanded and presented in Fig. 5. The influence of electrostatic interactions in the crystal-packing arrangements of DTDA species has been noted elsewhere (Rawson & Palacio, 2001). These typically occur between the partially positively charged S atoms and atoms with partial negative charge, including the ring N atoms and pendant atoms on the aryl ring or other groups.

The co-packing of monomers and dimers in (Ic) gives a rare opportunity to compare the molecular structures of dimerized and monomeric DTDA species that are chemically identical and that are under identical externally applied conditions. In particular, the mean S—S bond length in the DTDA ring has been a measure of interest (Banister et al., 1990). The singly occupied molecular orbital (SOMO) of the neutral DTDA radical is a π* orbital delocalized over the S and N atoms of the heterocycle. Therefore, lengthening of the S—S bond can be used as an indication of increased occupation of this molecular orbital. In (Ic), the S—S bond of Molecule 1 is slightly shorter than that of Molecule 2 (Table 1). However, assumptions regarding the electronic implications of this small difference should be made with caution, since the S—S bonds in (Ia) are shorter than those of Molecule 1 in (Ic), and the S—S bonds in (Ib) are roughly the same length as those of Molecule 2 in (Ic) (Table 1).

Comparing other geometric features of the molecules in (Ia) and (Ib) with those in (Ic), we find that the twist angles between the DTDA and aryl rings (Table 1) for both molecules in the asymmetric unit of (Ic) are larger than for either molecule in the asymmetric unit of (Ia) and for either molecule in the asymmetric unit of (Ib). In (Ic), the twist angle is largest in Molecule 1, permitting close lateral interactions between neighbouring DTDA rings in the one-dimensional chains of monomers.

It is, perhaps, unsurprizing that more than one polymorphic form of (I) can be isolated under a given set of conditions. The crystal packing of DTDA radicals in general is notoriously difficult to predict, although the norm is the formation of ππ dimers. For (I), the intermolecular interactions appear to include weak electrostatic forces competing with the four-centred two-electron S—S bonding interactions that generate trans-antarafacial and cis-cofacial ππ dimers. Other factors also contribute, such as the large twist angle between the aryl and DTDA ring planes, which likely results from repulsion between the exocyclic N-atom lone pairs and the F atoms at the ortho-positions of the phenyl ring. This twisting allows for packing of the monomers into one-dimensional chains. The low melting point of (I) (<313 K under an inert atmosphere) hints at relatively small lattice energies and is reminiscent of perfluoroalkyl-substituted DTDA radicals that are liquids at temperatures < 333 K (Shuvaev et al., 2008).

Dimers of DTDA radicals are generally considered to be diamagnetic and of little interest in terms of material properties. The monomers in (Ic), however, can be expected to remain paramagnetic. The close lateral contacts between these monomeric radicals, the one-dimensional orientation of the resulting chains, and the isolation of these chains from one another by arrays of dimers, are all features unique to (Ic). Furthermore, the sum of these features is a molecular material for which the structure suggests the possibility of strong intermolecular magnetic exchange coupling, probably antiferromagnetic in nature. We are currently attempting to isolate a pure sample of (Ic) large enough to perform magnetic measurements and conductivity tests. This is challenging, owing in part to co-sublimation of crystals with different habits and in part to the low melting point of all three polymorphs of (I), which impedes extensive handling of the samples.

Experimental top

The synthesis of (I) was achieved following standard procedures for the preparation of DTDA radicals (Boeré et al., 1987; Del Bel Belluz et al., 1989). Large purple–black block and plate crystals of polymorph (Ia) were grown by sublimation at 323 K under a static vacuum of 10−2 Torr over several days, green–bronze needles and blocks of (Ib) were grown by sublimation at 308 K under a static vacuum of 10−2 Torr within 24 h, and purple–black block [Blue–red needles in CIF tables - please clarify] crystals of (Ic) were grown by sublimation at 354 K under a static vacuum of 10−3 Torr over several days.

Refinement top

H atoms were positioned geometrically and refined using a riding model, with C—H = 0.95 Å and with Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: COLLECT (Nonius, 2001); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997); data reduction: DENZO-SMN (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL/PC (Sheldrick, 2008); software used to prepare material for publication: SHELXTL/PC (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The crystal structures of the two molecules in the asymmetric unit of (Ic), showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as small spheres of arbitrary radii. The monomeric molecule (Molecule 1) is labelled S1, S2, N3 etc. and the dimerized molecule (Molecule 2) is labelled S21, S22, N23 etc.
[Figure 2] Fig. 2. The trans-antarafacial mode of dimerization observed for Molecule 2, i.e. 50% of the molecules in (Ic). [Symmetry code: (i) 1 − x, 2 − y, 1 − z.]
[Figure 3] Fig. 3. In polymorph (Ic), (a) the Molecule 2 dimers pack along [110] with ππ stacking of aryl moieties, and (b) the Molecule 1 monomers pack in one-dimensional chains along [010], with coplanar DTDA rings, directed by intermolecular S···N contacts. [Symmetry codes: (i) 1 − x, 2 − y, 1 − z; (ii) 1 + x, 1 + y, z; (iii) −x, 1 − y, 1 − z; (iv) −x, 1/2 + y, 1/2 − z; (v) −x, y − 1/2, 1/2 − z; (vi) x, y − 1, z.]
[Figure 4] Fig. 4. In order to illustrate the packing of the dimers, together with the one-dimensional chains of monomers, a section of (Ic) is shown from two different perspectives, (a) down the a axis and (b) down the b axis.
[Figure 5] Fig. 5. In (Ic), short lateral contacts between atom F12 of a monomeric molecule and atoms S21i and S22i of a neighbouring dimerized molecule direct the co-packing of the dimers with the one-dimensional chains of monomers. [Symmetry code: (i) 1 − x, 2 − y, 1 − z.]
4-(2,6-difluorophenyl)-1,2,3,5-dithiadiazolyl top
Crystal data top
C7H3F2N2S2F(000) = 872
Mr = 217.23Dx = 1.803 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 6691 reflections
a = 10.3839 (5) Åθ = 2.0–27.5°
b = 7.9745 (3) ŵ = 0.64 mm1
c = 20.5463 (8) ÅT = 110 K
β = 109.846 (2)°Needle, blue-red
V = 1600.32 (12) Å30.40 × 0.11 × 0.05 mm
Z = 8
Data collection top
Nonius KappaCCD
2831 independent reflections
Radiation source: fine-focus sealed tube2045 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.085
ϕ scans, and ω scans with κ offsetsθmax = 25.0°, θmin = 2.8°
Absorption correction: multi-scan
(DENZO-SMN; Otwinowski & Minor, 1997)
h = 1212
Tmin = 0.783, Tmax = 0.969k = 99
141999 measured reflectionsl = 2424
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)] = 0.039Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.092H-atom parameters constrained
S = 0.99 w = 1/[σ2(Fo2) + (0.0459P)2]
where P = (Fo2 + 2Fc2)/3
2831 reflections(Δ/σ)max < 0.001
235 parametersΔρmax = 0.32 e Å3
0 restraintsΔρmin = 0.49 e Å3
Crystal data top
C7H3F2N2S2V = 1600.32 (12) Å3
Mr = 217.23Z = 8
Monoclinic, P21/cMo Kα radiation
a = 10.3839 (5) ŵ = 0.64 mm1
b = 7.9745 (3) ÅT = 110 K
c = 20.5463 (8) Å0.40 × 0.11 × 0.05 mm
β = 109.846 (2)°
Data collection top
Nonius KappaCCD
2831 independent reflections
Absorption correction: multi-scan
(DENZO-SMN; Otwinowski & Minor, 1997)
2045 reflections with I > 2σ(I)
Tmin = 0.783, Tmax = 0.969Rint = 0.085
141999 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0390 restraints
wR(F2) = 0.092H-atom parameters constrained
S = 0.99Δρmax = 0.32 e Å3
2831 reflectionsΔρmin = 0.49 e Å3
235 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 F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > σ(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ 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
S10.01436 (8)0.99771 (9)0.26038 (4)0.0214 (2)
S20.18635 (8)1.15194 (9)0.28564 (4)0.0214 (2)
F120.42018 (15)0.74548 (19)0.42224 (8)0.0221 (4)
F130.24386 (16)0.6340 (2)0.18422 (8)0.0255 (4)
N30.2970 (2)0.9981 (3)0.30063 (12)0.0186 (6)
N50.1030 (2)0.8243 (3)0.27239 (13)0.0202 (6)
C40.2381 (3)0.8462 (4)0.29171 (14)0.0180 (7)
C60.3274 (3)0.6950 (4)0.30268 (15)0.0166 (7)
C70.4155 (3)0.6476 (4)0.36723 (15)0.0182 (7)
C80.4960 (3)0.5079 (4)0.37855 (16)0.0198 (7)
C90.4918 (3)0.4096 (4)0.32219 (16)0.0222 (7)
C100.4069 (3)0.4520 (4)0.25647 (16)0.0213 (7)
C110.3270 (3)0.5923 (4)0.24851 (15)0.0192 (7)
S210.32455 (7)1.11148 (10)0.47806 (4)0.0215 (2)
S220.40824 (8)0.95293 (10)0.56339 (4)0.0206 (2)
F320.23937 (16)0.50462 (19)0.45518 (9)0.0278 (5)
F330.08452 (16)0.9331 (2)0.43019 (9)0.0270 (4)
N230.2892 (2)0.8106 (3)0.53573 (12)0.0186 (6)
N250.1958 (2)0.9884 (3)0.43985 (12)0.0186 (6)
C240.1947 (3)0.8477 (4)0.47445 (15)0.0188 (7)
C260.0835 (3)0.7248 (4)0.44455 (14)0.0172 (7)
C270.1071 (3)0.5558 (4)0.43745 (15)0.0203 (7)
C280.0059 (3)0.4380 (4)0.41340 (15)0.0233 (7)
C290.1287 (3)0.4917 (4)0.39476 (15)0.0258 (8)
C300.1592 (3)0.6584 (4)0.39992 (15)0.0240 (8)
C310.0535 (3)0.7701 (4)0.42415 (15)0.0204 (7)
Atomic displacement parameters (Å2) top
S10.0177 (4)0.0175 (5)0.0279 (5)0.0004 (3)0.0062 (3)0.0011 (3)
S20.0210 (4)0.0158 (4)0.0266 (5)0.0003 (3)0.0068 (4)0.0007 (3)
F120.0229 (9)0.0221 (10)0.0209 (10)0.0003 (7)0.0068 (8)0.0035 (8)
F130.0289 (10)0.0281 (11)0.0179 (10)0.0030 (8)0.0058 (8)0.0001 (8)
N30.0171 (13)0.0154 (15)0.0221 (15)0.0018 (11)0.0049 (11)0.0007 (10)
N50.0160 (14)0.0159 (15)0.0290 (16)0.0032 (11)0.0079 (12)0.0016 (12)
C40.0220 (17)0.0172 (18)0.0152 (17)0.0001 (13)0.0069 (14)0.0002 (12)
C60.0150 (16)0.0129 (17)0.0238 (18)0.0023 (13)0.0092 (13)0.0002 (13)
C70.0194 (16)0.0172 (17)0.0184 (18)0.0033 (13)0.0071 (14)0.0039 (13)
C80.0170 (16)0.0234 (19)0.0195 (18)0.0006 (14)0.0069 (14)0.0010 (13)
C90.0214 (17)0.0157 (18)0.032 (2)0.0051 (13)0.0126 (15)0.0023 (14)
C100.0241 (18)0.0176 (17)0.0233 (18)0.0007 (14)0.0095 (15)0.0063 (14)
C110.0202 (17)0.0202 (18)0.0161 (17)0.0014 (14)0.0048 (14)0.0047 (13)
S210.0217 (4)0.0171 (5)0.0252 (5)0.0001 (3)0.0072 (4)0.0021 (3)
S220.0198 (4)0.0218 (5)0.0191 (4)0.0017 (3)0.0053 (3)0.0001 (3)
F320.0227 (10)0.0197 (11)0.0413 (12)0.0022 (8)0.0112 (9)0.0010 (8)
F330.0220 (10)0.0241 (11)0.0335 (11)0.0043 (8)0.0074 (8)0.0010 (8)
N230.0175 (13)0.0169 (14)0.0200 (15)0.0001 (11)0.0047 (12)0.0001 (11)
N250.0157 (13)0.0180 (15)0.0219 (15)0.0020 (11)0.0063 (11)0.0025 (11)
C240.0172 (16)0.0217 (18)0.0201 (18)0.0040 (13)0.0098 (14)0.0010 (14)
C260.0186 (16)0.0186 (18)0.0143 (17)0.0015 (13)0.0054 (13)0.0015 (12)
C270.0177 (17)0.0246 (19)0.0195 (18)0.0035 (14)0.0076 (14)0.0049 (14)
C280.0276 (19)0.0195 (18)0.0239 (19)0.0024 (15)0.0103 (15)0.0004 (14)
C290.0275 (18)0.030 (2)0.0189 (19)0.0108 (15)0.0068 (15)0.0016 (14)
C300.0193 (17)0.031 (2)0.0196 (18)0.0033 (14)0.0045 (14)0.0024 (14)
C310.0248 (18)0.0193 (18)0.0170 (18)0.0022 (14)0.0068 (14)0.0013 (13)
Geometric parameters (Å, º) top
S1—N51.633 (2)S21—N251.629 (2)
S1—S22.0838 (10)S21—S222.0960 (11)
S2—N31.637 (2)S22—N231.632 (2)
F12—C71.361 (3)F32—C271.359 (3)
F13—C111.352 (3)F33—C311.355 (3)
N3—C41.341 (3)N23—C241.341 (3)
N5—C41.333 (3)N25—C241.330 (3)
C4—C61.491 (4)C24—C261.480 (4)
C6—C111.381 (4)C26—C271.386 (4)
C6—C71.384 (4)C26—C311.387 (4)
C7—C81.364 (4)C27—C281.370 (4)
C8—C91.387 (4)C28—C291.386 (4)
C9—C101.381 (4)C29—C301.379 (4)
C10—C111.369 (4)C30—C311.369 (4)
N5—S1—S294.07 (9)N25—S21—S2294.53 (9)
N3—S2—S195.26 (9)N23—S22—S2194.50 (9)
C4—N3—S2113.1 (2)C24—N23—S22113.6 (2)
C4—N5—S1114.6 (2)C24—N25—S21113.9 (2)
N5—C4—N3123.0 (3)N25—C24—N23123.5 (3)
N5—C4—C6118.5 (3)N25—C24—C26118.9 (3)
N3—C4—C6118.6 (2)N23—C24—C26117.6 (3)
C11—C6—C7115.5 (3)C27—C26—C31114.9 (3)
C11—C6—C4121.8 (3)C27—C26—C24123.2 (3)
C7—C6—C4122.7 (3)C31—C26—C24121.9 (3)
F12—C7—C8118.7 (3)F32—C27—C28118.2 (3)
F12—C7—C6117.7 (3)F32—C27—C26117.5 (3)
C8—C7—C6123.6 (3)C28—C27—C26124.2 (3)
C7—C8—C9118.4 (3)C27—C28—C29117.8 (3)
C10—C9—C8120.4 (3)C30—C29—C28120.8 (3)
C11—C10—C9118.5 (3)C31—C30—C29118.6 (3)
F13—C11—C10118.6 (3)F33—C31—C30118.1 (3)
F13—C11—C6117.9 (3)F33—C31—C26118.3 (3)
C10—C11—C6123.6 (3)C30—C31—C26123.6 (3)
N5—S1—S2—N30.18 (13)N25—S21—S22—N230.22 (12)
S1—S2—N3—C40.2 (2)S21—S22—N23—C240.7 (2)
S2—S1—N5—C40.1 (2)S22—S21—N25—C240.3 (2)
S1—N5—C4—N30.0 (4)S21—N25—C24—N231.0 (4)
S1—N5—C4—C6178.9 (2)S21—N25—C24—C26179.3 (2)
S2—N3—C4—N50.2 (4)S22—N23—C24—N251.2 (4)
S2—N3—C4—C6179.1 (2)S22—N23—C24—C26179.1 (2)
N5—C4—C6—C1167.7 (4)N25—C24—C26—C27129.4 (3)
N3—C4—C6—C11111.2 (3)N23—C24—C26—C2750.9 (4)
N5—C4—C6—C7112.1 (3)N25—C24—C26—C3153.4 (4)
N3—C4—C6—C769.0 (4)N23—C24—C26—C31126.3 (3)
C11—C6—C7—F12179.6 (2)C31—C26—C27—F32178.6 (2)
C4—C6—C7—F120.6 (4)C24—C26—C27—F324.1 (4)
C11—C6—C7—C81.2 (4)C31—C26—C27—C281.0 (4)
C4—C6—C7—C8178.6 (3)C24—C26—C27—C28176.4 (3)
F12—C7—C8—C9179.3 (3)F32—C27—C28—C29179.3 (2)
C6—C7—C8—C91.4 (5)C26—C27—C28—C290.2 (4)
C7—C8—C9—C100.7 (4)C27—C28—C29—C300.4 (4)
C8—C9—C10—C110.3 (4)C28—C29—C30—C310.3 (5)
C9—C10—C11—F13179.9 (3)C29—C30—C31—F33178.8 (3)
C9—C10—C11—C60.5 (5)C29—C30—C31—C260.6 (5)
C7—C6—C11—F13179.3 (2)C27—C26—C31—F33179.4 (2)
C4—C6—C11—F130.9 (4)C24—C26—C31—F332.0 (4)
C7—C6—C11—C100.1 (4)C27—C26—C31—C301.2 (4)
C4—C6—C11—C10179.7 (3)C24—C26—C31—C30176.2 (3)

Experimental details

Crystal data
Chemical formulaC7H3F2N2S2
Crystal system, space groupMonoclinic, P21/c
Temperature (K)110
a, b, c (Å)10.3839 (5), 7.9745 (3), 20.5463 (8)
β (°) 109.846 (2)
V3)1600.32 (12)
Radiation typeMo Kα
µ (mm1)0.64
Crystal size (mm)0.40 × 0.11 × 0.05
Data collection
DiffractometerNonius KappaCCD
Absorption correctionMulti-scan
(DENZO-SMN; Otwinowski & Minor, 1997)
Tmin, Tmax0.783, 0.969
No. of measured, independent and
observed [I > 2σ(I)] reflections
141999, 2831, 2045
(sin θ/λ)max1)0.595
R[F2 > 2σ(F2)], wR(F2), S 0.039, 0.092, 0.99
No. of reflections2831
No. of parameters235
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.32, 0.49

Computer programs: COLLECT (Nonius, 2001), DENZO-SMN (Otwinowski & Minor, 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL/PC (Sheldrick, 2008).

Selected structural parameters (Å, °) for polymorphs (Ia), (Ib) and (Ic) top
(Clarke et al., 2010)(Clarke et al., 2010)(This work)
Temperature150 K110 K
S—S bondMolecule 12.080 (3)Molecule 12.0917 (7)Molecule 12.0838 (10)
Molecule 22.081 (3)Molecule 22.0944 (7)Molecule 22.0960 (11)
Twist angle between mean planes of aryl and DTDA ringsMolecule 148.7 (11)Molecule 129.4 (3)Molecule 168.5 (4)
Molecule 247.7 (8)Molecule 224.9 (3)Molecule 252.2 (4)
Intra-dimer S···S contact distanceS11···S213.069 (3)S11···S213.2167 (7)S21···S22i3.208 (1)
S12···S223.129 (3)S12···S223.0692 (8)
Angle between mean planes of DTDA rings in a dimer18.1 (8)6.4 (6)0.00 (0)
Lateral intermolecular contacts defining one-dimensional chainsn/an/an/an/aS1···N5iv2.857 (2)
S2···N5iv3.147 (2)
S2···S1iv3.392 (4)
Intermolecular contacts between dimers and one-dimensional chainsn/an/an/an/aF12···S21i2.973 (3)
F12···S22i2.948 (3)
Notes: Molecules 1 and 2 in the asymmetric unit are labelled S1, S2, N3 etc., and S21, S22, N23 etc., respectively. In (Ic), Molecule 1 is the monomer and Molecule 2 is dimerized. [Symmetry codes: (i) 1 − x, 2 − y, 1 − z; (iv) −x, 1/2 + y, 1/2 − z.]

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