Bis(2-trifluoro-methyl-1H-benzimidazol-3-ium) naphthalene-1,5-disulfonate.

The asymmetric unit of the title compound, C(8)H(6)F(3)N(2) (+)·0.5C(10)H(6)O(6)S(2) (2-), consists of one 2-trifluoro-methyl-1H-benz-imidazol-3-ium cation and a half naphthalene-1,5-disulfate anion, which are linked by an N-H⋯O hydrogen bond. The anion sits across a centre of symmetry. The atoms of the benzimidazole ring are nearly coplanar (r.m.s. deviation of the fitted atoms = 0.0085 Å) and the triflouromethyl group lies out of this plane. In the crystal, the cations are linked to adjacent anions by N-H⋯O hydrogen bonds, forming a ladder structure parallel to the a axis in which the anions form the rungs. Adjacent ladders are linked by weak C-H⋯O inter-actions, forming sheets parallel to the ac plane.

Related literature

The title compound was studied as part of a search for ferroelectric complexes. For background to ferroelectric complexes, see: Fu et al. (2011 ▶); Zhang et al. (2010 ▶). For related structures, see: Liu (2011a ▶,b ▶). For graph-set analysis, see: Bernstein et al. (1995 ▶).

Experimental

Crystal data

2C8H6F3N2 +·C10H6O6S2 2−

M = 660.56

Triclinic,

a = 9.3910 (19) Å

b = 9.4943 (19) Å

c = 9.976 (2) Å

α = 109.32 (3)°

β = 96.86 (3)°

γ = 119.59 (3)°

V = 685.2 (5) Å3

Z = 1

Mo Kα radiation

μ = 0.29 mm−1

T = 293 K

0.36 × 0.32 × 0.28 mm

Data collection

Rigaku Mercury2 diffractometer

Absorption correction: multi-scan (CrystalClear; Rigaku, 2005 ▶) T min = 0.903, T max = 0.921

7215 measured reflections

3136 independent reflections

2361 reflections with I > 2σ(I)

R int = 0.042

Refinement

R[F 2 > 2σ(F 2)] = 0.053

wR(F 2) = 0.132

S = 1.10

3136 reflections

227 parameters

36 restraints

H-atom parameters constrained

Δρmax = 0.23 e Å−3

Δρmin = −0.42 e Å−3

Data collection: CrystalClear (Rigaku, 2005 ▶); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: PLATON (Spek, 2009) ▶; software used to prepare material for publication: SHELXTL (Sheldrick, 2008 ▶).

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536812000049/go2042sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812000049/go2042Isup2.hkl

Supplementary material file. DOI: 10.1107/S1600536812000049/go2042Isup3.cml

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

2C8H6F3N2+·C10H6O6S22−	V = 685.2 (5) Å3
Mr = 660.56	Z = 1
Triclinic, P1	F(000) = 336
Hall symbol: -P 1	Dx = 1.601 Mg m−3
a = 9.3910 (19) Å	Mo Kα radiation, λ = 0.71073 Å
b = 9.4943 (19) Å	θ = 3.4–26°
c = 9.976 (2) Å	µ = 0.29 mm−1
α = 109.32 (3)°	T = 293 K
β = 96.86 (3)°	Block, colourless
γ = 119.59 (3)°	0.36 × 0.32 × 0.28 mm

Rigaku Mercury2 diffractometer	3136 independent reflections
Radiation source: fine-focus sealed tube	2361 reflections with I > 2σ(I)
graphite	Rint = 0.042
CCD_Profile_fitting scans	θmax = 27.5°, θmin = 3.2°
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)	h = −12→12
Tmin = 0.903, Tmax = 0.921	k = −12→12
7215 measured reflections	l = −12→12

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)] = 0.053	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.132	H-atom parameters constrained
S = 1.10	w = 1/[σ2(Fo2) + (0.0517P)2 + 0.2409P] where P = (Fo2 + 2Fc2)/3
3136 reflections	(Δ/σ)max = 0.011
227 parameters	Δρmax = 0.23 e Å−3
36 restraints	Δρmin = −0.42 e Å−3

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.

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 > 2sigma(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.

	x	y	z	Uiso*/Ueq	Occ. (<1)
S1	1.05784 (8)	0.72945 (9)	0.37188 (7)	0.03242 (19)
O1	0.9734 (2)	0.8147 (3)	0.3414 (2)	0.0398 (4)
O2	1.2456 (2)	0.8519 (2)	0.4164 (2)	0.0440 (5)
O3	1.0035 (3)	0.6558 (3)	0.4750 (2)	0.0532 (5)
C11	0.9978 (3)	0.5476 (3)	0.1973 (3)	0.0300 (5)
C12	0.9359 (3)	0.3826 (3)	0.1952 (3)	0.0362 (6)
H12	0.9236	0.3679	0.2817	0.043*
C13	0.8913 (4)	0.2364 (3)	0.0616 (3)	0.0413 (6)
H13	0.8468	0.1234	0.0594	0.050*
C14	0.9117 (3)	0.2556 (3)	−0.0659 (3)	0.0365 (6)
H14	0.8816	0.1559	−0.1531	0.044*
C110	1.0219 (3)	0.5750 (3)	0.0670 (3)	0.0286 (5)
N1	0.4697 (3)	0.7605 (3)	0.4315 (2)	0.0360 (5)
H1	0.3796	0.7607	0.4033	0.043*
N3	0.7062 (3)	0.7706 (3)	0.4334 (2)	0.0339 (5)
H3	0.7924	0.7781	0.4066	0.041*
C2	0.5853 (3)	0.7790 (3)	0.3630 (3)	0.0352 (6)
C4	0.4442 (4)	0.7162 (4)	0.6660 (4)	0.0518 (7)
H4	0.3417	0.7094	0.6641	0.062*
C5	0.5303 (5)	0.7028 (5)	0.7769 (4)	0.0608 (9)
H5	0.4851	0.6872	0.8528	0.073*
C6	0.6826 (5)	0.7115 (5)	0.7797 (4)	0.0581 (8)
H6	0.7369	0.7027	0.8579	0.070*
C7	0.7555 (4)	0.7326 (4)	0.6704 (3)	0.0468 (7)
H7	0.8567	0.7366	0.6718	0.056*
C8	0.6707 (3)	0.7477 (3)	0.5582 (3)	0.0335 (5)
C9	0.5194 (3)	0.7408 (3)	0.5562 (3)	0.0353 (6)
C21	0.5768 (4)	0.8018 (5)	0.2213 (4)	0.0523 (7)
F1	0.5176 (12)	0.9023 (10)	0.2234 (8)	0.0857 (19)	0.653 (12)
F2	0.4588 (17)	0.6460 (7)	0.1027 (5)	0.119 (3)	0.653 (12)
F3	0.7210 (9)	0.8792 (17)	0.2048 (11)	0.113 (3)	0.653 (12)
F1A	0.450 (2)	0.797 (4)	0.1674 (19)	0.114 (5)	0.347 (12)
F2A	0.590 (3)	0.6822 (19)	0.1208 (11)	0.086 (3)	0.347 (12)
F3A	0.720 (2)	0.9515 (16)	0.2418 (15)	0.118 (6)	0.347 (12)

	U11	U22	U33	U12	U13	U23
S1	0.0354 (3)	0.0412 (4)	0.0305 (3)	0.0274 (3)	0.0148 (3)	0.0162 (3)
O1	0.0412 (10)	0.0540 (11)	0.0460 (10)	0.0373 (9)	0.0240 (8)	0.0255 (9)
O2	0.0311 (10)	0.0428 (11)	0.0480 (11)	0.0247 (9)	0.0066 (8)	0.0066 (9)
O3	0.0827 (15)	0.0612 (13)	0.0382 (11)	0.0485 (12)	0.0333 (11)	0.0294 (10)
C11	0.0283 (12)	0.0354 (13)	0.0308 (12)	0.0195 (11)	0.0136 (10)	0.0162 (10)
C12	0.0424 (14)	0.0436 (15)	0.0357 (13)	0.0274 (13)	0.0205 (11)	0.0245 (12)
C13	0.0527 (17)	0.0303 (13)	0.0433 (15)	0.0215 (13)	0.0205 (13)	0.0214 (12)
C14	0.0407 (14)	0.0325 (13)	0.0369 (14)	0.0204 (12)	0.0153 (11)	0.0164 (11)
C110	0.0250 (11)	0.0332 (13)	0.0311 (12)	0.0174 (10)	0.0121 (9)	0.0162 (10)
N1	0.0281 (10)	0.0427 (12)	0.0436 (12)	0.0242 (10)	0.0138 (9)	0.0189 (10)
N3	0.0331 (11)	0.0426 (12)	0.0399 (11)	0.0274 (10)	0.0193 (9)	0.0212 (10)
C2	0.0352 (13)	0.0353 (14)	0.0383 (14)	0.0233 (12)	0.0143 (11)	0.0143 (11)
C4	0.0491 (17)	0.0541 (18)	0.0566 (18)	0.0284 (15)	0.0328 (15)	0.0261 (15)
C5	0.076 (2)	0.064 (2)	0.0495 (18)	0.0369 (19)	0.0368 (17)	0.0315 (17)
C6	0.075 (2)	0.067 (2)	0.0467 (17)	0.0448 (19)	0.0222 (16)	0.0333 (16)
C7	0.0507 (17)	0.0555 (18)	0.0481 (16)	0.0368 (15)	0.0179 (14)	0.0270 (14)
C8	0.0351 (13)	0.0331 (13)	0.0366 (13)	0.0214 (11)	0.0159 (11)	0.0154 (11)
C9	0.0336 (13)	0.0346 (13)	0.0404 (14)	0.0205 (11)	0.0171 (11)	0.0164 (11)
C21	0.059 (2)	0.069 (2)	0.0493 (18)	0.0446 (18)	0.0237 (16)	0.0337 (17)
F1	0.130 (6)	0.112 (4)	0.072 (4)	0.096 (4)	0.034 (3)	0.056 (3)
F2	0.187 (8)	0.079 (3)	0.037 (2)	0.052 (4)	0.009 (3)	0.0200 (19)
F3	0.086 (4)	0.235 (9)	0.130 (6)	0.112 (5)	0.079 (4)	0.151 (6)
F1A	0.083 (7)	0.238 (15)	0.095 (9)	0.116 (9)	0.044 (6)	0.108 (10)
F2A	0.161 (10)	0.099 (7)	0.036 (4)	0.096 (7)	0.043 (5)	0.031 (4)
F3A	0.160 (11)	0.066 (5)	0.068 (5)	0.016 (5)	0.056 (6)	0.041 (4)

S1—O3	1.435 (2)	N3—H3	0.8600
S1—O2	1.451 (2)	C2—C21	1.498 (4)
S1—O1	1.4547 (18)	C4—C5	1.369 (5)
S1—C11	1.774 (3)	C4—C9	1.395 (4)
C11—C12	1.367 (3)	C4—H4	0.9300
C11—C110	1.430 (3)	C5—C6	1.388 (5)
C12—C13	1.395 (4)	C5—H5	0.9300
C12—H12	0.9300	C6—C7	1.373 (4)
C13—C14	1.366 (3)	C6—H6	0.9300
C13—H13	0.9300	C7—C8	1.384 (4)
C14—C110i	1.414 (3)	C7—H7	0.9300
C14—H14	0.9300	C8—C9	1.386 (3)
C110—C14i	1.414 (3)	C21—F1A	1.223 (11)
C110—C110i	1.419 (5)	C21—F3	1.246 (7)
N1—C2	1.321 (3)	C21—F2A	1.311 (8)
N1—C9	1.380 (3)	C21—F2	1.314 (6)
N1—H1	0.8600	C21—F3A	1.314 (12)
N3—C2	1.312 (3)	C21—F1	1.317 (6)
N3—C8	1.384 (3)
O3—S1—O2	113.71 (13)	N1—C2—C21	124.3 (2)
O3—S1—O1	112.87 (11)	C5—C4—C9	116.0 (3)
O2—S1—O1	110.44 (11)	C5—C4—H4	122.0
O3—S1—C11	107.83 (12)	C9—C4—H4	122.0
O2—S1—C11	104.13 (11)	C4—C5—C6	122.2 (3)
O1—S1—C11	107.24 (11)	C4—C5—H5	118.9
C12—C11—C110	121.5 (2)	C6—C5—H5	118.9
C12—C11—S1	117.00 (18)	C7—C6—C5	121.9 (3)
C110—C11—S1	121.37 (17)	C7—C6—H6	119.0
C11—C12—C13	119.2 (2)	C5—C6—H6	119.0
C11—C12—H12	120.4	C6—C7—C8	116.5 (3)
C13—C12—H12	120.4	C6—C7—H7	121.7
C14—C13—C12	121.4 (2)	C8—C7—H7	121.7
C14—C13—H13	119.3	N3—C8—C7	132.2 (2)
C12—C13—H13	119.3	N3—C8—C9	106.2 (2)
C13—C14—C110i	120.9 (2)	C7—C8—C9	121.5 (2)
C13—C14—H14	119.6	N1—C9—C8	106.8 (2)
C110i—C14—H14	119.6	N1—C9—C4	131.4 (3)
C14i—C110—C110i	118.7 (3)	C8—C9—C4	121.7 (3)
C14i—C110—C11	123.1 (2)	F1A—C21—F2A	110.9 (8)
C110i—C110—C11	118.3 (3)	F3—C21—F2	112.5 (5)
C2—N1—C9	107.7 (2)	F1A—C21—F3A	109.7 (11)
C2—N1—H1	126.2	F2A—C21—F3A	99.4 (8)
C9—N1—H1	126.2	F3—C21—F1	106.2 (5)
C2—N3—C8	108.1 (2)	F2—C21—F1	103.2 (5)
C2—N3—H3	126.0	F3—C21—C2	113.7 (4)
C8—N3—H3	126.0	F2—C21—C2	110.7 (3)
N3—C2—N1	111.2 (2)	F1—C21—C2	109.8 (4)
N3—C2—C21	124.5 (2)
O3—S1—C11—C12	−8.3 (2)	C6—C7—C8—N3	179.7 (3)
O2—S1—C11—C12	112.8 (2)	C6—C7—C8—C9	−0.4 (4)
O1—S1—C11—C12	−130.1 (2)	C2—N1—C9—C8	−0.2 (3)
O3—S1—C11—C110	174.97 (18)	C2—N1—C9—C4	−179.7 (3)
O2—S1—C11—C110	−63.9 (2)	N3—C8—C9—N1	−0.3 (3)
O1—S1—C11—C110	53.2 (2)	C7—C8—C9—N1	179.8 (2)
C110—C11—C12—C13	−1.5 (4)	N3—C8—C9—C4	179.2 (2)
S1—C11—C12—C13	−178.29 (19)	C7—C8—C9—C4	−0.7 (4)
C11—C12—C13—C14	1.4 (4)	C5—C4—C9—N1	−179.5 (3)
C12—C13—C14—C110i	−0.4 (4)	C5—C4—C9—C8	1.1 (4)
C12—C11—C110—C14i	−179.0 (2)	N3—C2—C21—F1A	176.3 (14)
S1—C11—C110—C14i	−2.3 (3)	N1—C2—C21—F1A	−2.1 (15)
C12—C11—C110—C110i	0.6 (4)	N3—C2—C21—F3	−25.8 (8)
S1—C11—C110—C110i	177.3 (2)	N1—C2—C21—F3	155.8 (7)
C8—N3—C2—N1	−0.9 (3)	N3—C2—C21—F2A	50.4 (10)
C8—N3—C2—C21	−179.5 (2)	N1—C2—C21—F2A	−128.0 (10)
C9—N1—C2—N3	0.7 (3)	N3—C2—C21—F2	101.9 (8)
C9—N1—C2—C21	179.3 (2)	N1—C2—C21—F2	−76.5 (8)
C9—C4—C5—C6	−0.5 (5)	N3—C2—C21—F3A	−58.3 (10)
C4—C5—C6—C7	−0.6 (5)	N1—C2—C21—F3A	123.3 (10)
C5—C6—C7—C8	1.0 (5)	N3—C2—C21—F1	−144.7 (5)
C2—N3—C8—C7	−179.3 (3)	N1—C2—C21—F1	36.9 (6)
C2—N3—C8—C9	0.7 (3)

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3···O1	0.86	1.81	2.661 (3)	172
N1—H1···O2ii	0.86	1.84	2.650 (3)	155
C12—H12···O3iii	0.93	2.55	3.440 (3)	159

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N3—H3⋯O1	0.86	1.81	2.661 (3)	172
N1—H1⋯O2i	0.86	1.84	2.650 (3)	155
C12—H12⋯O3ii	0.93	2.55	3.440 (3)	159

Symmetry codes: (i) ; (ii) .