2,3,6,7-Tetrakis(2-cyano­ethyl­thio)­tetra­thia­fulvalene

The centrosymmetric title compound, C₁₈H₁₆N₄S₈, has a planar structure, with the exception of the four cyano­ethyl groups. The three-dimensional network is stabilized by a variety of S...S and S...C interactions.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.008 Å
• R factor = 0.065
• wR factor = 0.182
• Data-to-parameter ratio = 15.6

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry

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Computing details

Data collection: XSCANS (Bruker, 1996); cell refinement: XSCANS; data reduction: XSCANS; program(s) used to solve structure: SHELXTL (Bruker, 1997); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

(I)

Crystal data

C18H16N4S8	F(000) = 560
Mr = 544.82	Dx = 1.501 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
a = 5.1016 (13) Å	Cell parameters from 41 reflections
b = 26.753 (5) Å	θ = 5.1–12.4°
c = 8.8805 (15) Å	µ = 0.76 mm^−1
β = 96.031 (16)°	T = 293 K
V = 1205.3 (4) Å^3	Plate, orange
Z = 2	0.56 × 0.38 × 0.08 mm

Data collection

Bruker P4 diffractometer	1761 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.051
Graphite monochromator	θmax = 25.0°, θmin = 2.4°
θ/2θ scans	h = −1→6
Absorption correction: ψ scan (XSCANS; Bruker, 1996)	k = −31→1
Tmin = 0.75, Tmax = 0.951	l = −10→10
2991 measured reflections	3 standard reflections every 97 reflections
2104 independent reflections	intensity decay: 1%

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.065	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.182	H-atom parameters constrained
S = 1.10	w = 1/[σ^2(Fo^2) + (0.0792P)^2 + 2.9598P] where P = (Fo^2 + 2Fc^2)/3
2103 reflections	(Δ/σ)max < 0.001
135 parameters	Δρmax = 0.60 e Å^−3
6 restraints	Δρmin = −0.47 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq	Occ. (<1)
S1	0.7986 (3)	0.05385 (5)	−0.05407 (13)	0.0446 (4)
S2	0.6707 (2)	0.01046 (5)	0.23467 (12)	0.0427 (4)
S3	1.2355 (3)	0.11715 (5)	0.08630 (18)	0.0549 (4)
S4	1.1075 (3)	0.06611 (6)	0.41760 (14)	0.0490 (4)
N2	0.4018 (14)	0.1561 (3)	0.6944 (7)	0.092 (2)
C1	0.5971 (9)	0.01379 (18)	0.0371 (5)	0.0388 (11)
C2	0.9786 (9)	0.07572 (18)	0.1122 (5)	0.0397 (11)
C3	0.9223 (9)	0.05577 (18)	0.2432 (5)	0.0395 (11)
C4	1.0567 (13)	0.1715 (2)	0.0104 (6)	0.0580 (15)
H4A	1.1763	0.1929	−0.0381	0.070*
H4B	0.9191	0.1607	−0.0666	0.070*
C7	0.8580 (11)	0.0828 (2)	0.5401 (5)	0.0489 (12)
H7A	0.7210	0.0575	0.5314	0.059*
H7B	0.9372	0.0830	0.6443	0.059*
C8	0.7351 (11)	0.1331 (2)	0.5028 (6)	0.0556 (14)
H8A	0.8723	0.1583	0.5053	0.067*
H8B	0.6441	0.1324	0.4013	0.067*
C9	0.5478 (12)	0.1466 (2)	0.6110 (7)	0.0597 (15)
C5	0.9347 (14)	0.2011 (3)	0.1275 (8)	0.081 (2)
H5A	0.8397	0.2296	0.0815	0.097*
H5B	0.8126	0.1806	0.1771	0.097*
C6	1.153 (2)	0.2178 (4)	0.2370 (13)	0.087 (4)*	0.72 (2)
N1	1.335 (2)	0.2284 (4)	0.3186 (13)	0.121 (5)*	0.72 (2)
C6'	1.049 (5)	0.2199 (11)	0.2756 (18)	0.089 (10)*	0.28 (2)
N1'	1.159 (7)	0.2332 (12)	0.388 (2)	0.132 (15)*	0.28 (2)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.0442 (7)	0.0624 (8)	0.0271 (6)	0.0016 (6)	0.0036 (5)	0.0064 (5)
S2	0.0400 (7)	0.0637 (8)	0.0241 (6)	−0.0044 (6)	0.0012 (5)	0.0027 (5)
S3	0.0435 (8)	0.0531 (8)	0.0689 (10)	−0.0001 (6)	0.0098 (6)	0.0083 (7)
S4	0.0381 (7)	0.0742 (9)	0.0338 (7)	0.0009 (6)	−0.0011 (5)	−0.0077 (6)
N2	0.099 (5)	0.109 (5)	0.073 (4)	0.027 (4)	0.026 (4)	−0.012 (4)
C1	0.041 (3)	0.050 (3)	0.025 (2)	0.010 (2)	−0.0009 (17)	0.0001 (18)
C2	0.038 (3)	0.046 (3)	0.035 (2)	0.007 (2)	0.0037 (19)	0.001 (2)
C3	0.040 (3)	0.046 (3)	0.032 (2)	0.003 (2)	0.0019 (19)	−0.0035 (19)
C4	0.075 (4)	0.056 (3)	0.043 (3)	−0.003 (3)	0.003 (3)	0.007 (2)
C7	0.055 (3)	0.062 (3)	0.029 (2)	0.001 (3)	0.003 (2)	−0.001 (2)
C8	0.053 (3)	0.064 (3)	0.050 (3)	−0.001 (3)	0.010 (2)	−0.004 (3)
C9	0.055 (3)	0.071 (4)	0.052 (3)	0.009 (3)	−0.002 (3)	−0.004 (3)
C5	0.104 (6)	0.068 (4)	0.071 (4)	0.023 (4)	0.016 (4)	0.012 (3)

Geometric parameters (Å, º)

S1—C1	1.742 (5)	C4—H4B	0.9700
S1—C2	1.755 (5)	C7—C8	1.508 (8)
S2—C1	1.758 (4)	C7—H7A	0.9700
S2—C3	1.761 (5)	C7—H7B	0.9700
S3—C2	1.750 (5)	C8—C9	1.469 (8)
S3—C4	1.808 (6)	C8—H8A	0.9700
S4—C3	1.749 (5)	C8—H8B	0.9700
S4—C7	1.815 (5)	C5—C6'	1.4709 (10)
N2—C9	1.133 (8)	C5—C6	1.4709 (10)
C1—C1^i	1.350 (10)	C5—H5A	0.9700
C2—C3	1.339 (7)	C5—H5B	0.9700
C4—C5	1.494 (9)	C6—N1	1.1507 (9)
C4—H4A	0.9700	C6'—N1'	1.1510 (10)
C1—S1—C2	95.5 (2)	C8—C7—H7B	109.0
C1—S2—C3	95.0 (2)	S4—C7—H7B	109.0
C2—S3—C4	101.7 (3)	H7A—C7—H7B	107.8
C3—S4—C7	102.8 (2)	C9—C8—C7	111.1 (5)
C1^i—C1—S1	123.2 (5)	C9—C8—H8A	109.4
C1^i—C1—S2	121.9 (5)	C7—C8—H8A	109.4
S1—C1—S2	114.9 (3)	C9—C8—H8B	109.4
C3—C2—S3	126.8 (4)	C7—C8—H8B	109.4
C3—C2—S1	117.2 (4)	H8A—C8—H8B	108.0
S3—C2—S1	115.7 (3)	N2—C9—C8	178.7 (8)
C2—C3—S4	124.2 (4)	C6'—C5—C6	26.1 (9)
C2—C3—S2	117.3 (4)	C6'—C5—C4	130.4 (10)
S4—C3—S2	118.1 (3)	C6—C5—C4	106.2 (7)
C5—C4—S3	113.4 (4)	C6'—C5—H5A	104.0
C5—C4—H4A	108.9	C6—C5—H5A	110.5
S3—C4—H4A	108.9	C4—C5—H5A	110.5
C5—C4—H4B	108.9	C6'—C5—H5B	90.1
S3—C4—H4B	108.9	C6—C5—H5B	110.5
H4A—C4—H4B	107.7	C4—C5—H5B	110.5
C8—C7—S4	112.9 (4)	H5A—C5—H5B	108.7
C8—C7—H7A	109.0	N1—C6—C5	175.2 (12)
S4—C7—H7A	109.0	N1'—C6'—C5	174.4 (15)

Symmetry code: (i) −x+1, −y, −z.