(p-Phenyl­enedimethyl­ene)diammonium dichloride

In the title compound, C₈H₁₄N₂²⁺·2Cl⁻, the cation possesses a crystallographically imposed center of symmetry. The crystal packing is stabilized by inter­molecular N—H...Cl hydrogen bonds and π–π stacking inter­actions.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.038
• wR factor = 0.092
• Data-to-parameter ratio = 11.9

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low .......       0.98
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical .          ?
PLAT154_ALERT_1_C The su's on the Cell Angles are Equal (x 10000)         300 Deg.

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   3 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: SMART (Bruker, 2006); cell refinement: SAINT-Plus (Bruker, 2006); data reduction: SAINT-Plus; program(s) used to solve structure: DIRDIF99 (Beurskens et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLUTO (Meetsma, 2006) and PLATON (Spek, 2003); software used to prepare material for publication: PLATON.

(p-Phenylenedimethylene)diammonium dichloride

Crystal data

C8H14N2^2+·2Cl^−	Z = 1
Mr = 209.12	F(000) = 110
Triclinic, P1	The final unit cell was obtained from the xyz centroids of 1454 reflections after integration using the SAINTPLUS software package (Bruker, 2000). Reduced cell calculations did not indicate any higher metric lattice symmetry and examination of the finalatomic coordinates of the structure did not yield extra symmetry elements (Spek, 1988; Le Page 1987, 1988)
Hall symbol: -P 1	Dx = 1.405 Mg m^−3
a = 4.3496 (8) Å	Mo Kα radiation, λ = 0.71073 Å
b = 5.809 (1) Å	Cell parameters from 1454 reflections
c = 10.197 (2) Å	θ = 3.6–29.2°
α = 101.836 (3)°	µ = 0.61 mm^−1
β = 99.727 (3)°	T = 100 K
γ = 93.800 (3)°	Platelet, colourless
V = 247.18 (8) Å^3	0.17 × 0.08 × 0.03 mm

Data collection

Bruker SMART APEX CCD area-detector diffractometer	986 independent reflections
Radiation source: fine focus sealed Siemens Mo tube	881 reflections with I > 2σ(I)
Parallel mounted graphite monochromator	Rint = 0.046
Detector resolution: 4096x4096 / 62x62 (binned 512) pixels mm^-1	θmax = 26.4°, θmin = 3.6°
φ and ω scans	h = −5→5
Absorption correction: multi-scan (SADABS; Sheldrick, 2006)	k = −7→7
Tmin = 0.900, Tmax = 0.982	l = −12→12
1835 measured reflections

Refinement

Refinement on F^2	Primary atom site location: heavy-atom method
Least-squares matrix: full	Secondary atom site location: structure-invariant direct methods
R[F^2 > 2σ(F^2)] = 0.038	Hydrogen site location: difference Fourier map
wR(F^2) = 0.092	All H-atom parameters refined
S = 1.06	w = 1/[σ^2(Fo^2) + (0.0368P)^2 + 0.28P] where P = (Fo^2 + 2Fc^2)/3
986 reflections	(Δ/σ)max < 0.001
83 parameters	Δρmax = 0.36 e Å^−3
0 restraints	Δρmin = −0.25 e Å^−3

Special details

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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
N	0.5288 (5)	0.1941 (3)	0.8760 (2)	0.0158 (6)
C1	0.2753 (5)	0.1648 (4)	0.7529 (2)	0.0176 (7)
C2	0.3960 (5)	0.0804 (4)	0.6224 (2)	0.0144 (6)
C3	0.5593 (5)	0.2376 (4)	0.5657 (2)	0.0159 (6)
C4	0.3367 (5)	−0.1577 (4)	0.5556 (2)	0.0162 (6)
Cl	0.15450 (13)	0.29407 (9)	0.12289 (5)	0.0178 (2)
H1	0.108 (6)	0.050 (5)	0.761 (3)	0.016 (6)*
H1'	0.201 (7)	0.320 (5)	0.758 (3)	0.025 (7)*
H3	0.599 (6)	0.394 (5)	0.612 (3)	0.016 (6)*
H4	0.224 (6)	−0.268 (5)	0.595 (3)	0.018 (6)*
H5	0.669 (7)	0.323 (5)	0.884 (3)	0.019 (7)*
H5'	0.623 (6)	0.057 (5)	0.873 (3)	0.015 (6)*
H5"	0.433 (8)	0.229 (6)	0.951 (4)	0.035 (8)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N	0.0197 (10)	0.0149 (10)	0.0132 (10)	0.0042 (8)	0.0050 (8)	0.0016 (8)
C1	0.0161 (12)	0.0197 (12)	0.0179 (12)	0.0046 (9)	0.0056 (9)	0.0036 (9)
C2	0.0157 (11)	0.0154 (10)	0.0113 (10)	0.0050 (8)	0.0009 (8)	0.0012 (8)
C3	0.0181 (11)	0.0125 (10)	0.0165 (12)	0.0030 (8)	0.0030 (9)	0.0016 (9)
C4	0.0171 (11)	0.0153 (11)	0.0168 (11)	0.0019 (8)	0.0030 (9)	0.0047 (9)
Cl	0.0215 (3)	0.0153 (3)	0.0166 (3)	0.0035 (2)	0.0049 (2)	0.0021 (2)

Geometric parameters (Å, º)

N—C1	1.497 (3)	C2—C4	1.397 (3)
N—H5"	0.93 (4)	C3—C4^i	1.390 (3)
N—H5	0.92 (3)	C1—H1	0.98 (3)
N—H5'	0.92 (3)	C1—H1'	0.97 (3)
C1—C2	1.513 (3)	C3—H3	0.92 (3)
C2—C3	1.394 (3)	C4—H4	0.97 (3)
Cl···N^i	3.235 (2)	C4···C2^vi	3.496 (3)
Cl···N^ii	3.190 (2)	C3···H1'^x	3.08 (3)
Cl···N^iii	3.199 (2)	C4···H3^xi	3.03 (3)
Cl···N^iv	3.310 (2)	H1···H4	2.38 (4)
Cl···H1'^v	2.98 (3)	H1···H5'^ix	2.56 (4)
Cl···H1^vi	2.80 (3)	H1···Cl^vi	2.80 (3)
Cl···H5'^i	2.32 (3)	H1'···C3^ix	3.08 (3)
Cl···H5'^iv	3.14 (3)	H1'···Cl^v	2.98 (3)
Cl···H5"^iii	2.28 (4)	H1'···H3	2.54 (4)
Cl···H5^ii	2.32 (3)	H3···C4^xii	3.03 (3)
Cl···H5^iv	2.98 (3)	H3···H1'	2.54 (4)
Cl···H3^ii	2.92 (3)	H3···Cl^ii	2.92 (3)
N···Cl^vii	3.199 (2)	H4···H1	2.38 (4)
N···Cl^viii	3.310 (2)	H5···Cl^viii	2.98 (3)
N···Cl^i	3.235 (2)	H5···Cl^ii	2.32 (3)
N···Cl^ii	3.190 (2)	H5'···Cl^i	2.32 (3)
C1···C3^ix	3.467 (3)	H5'···H1^x	2.56 (4)
C2···C4^vi	3.496 (3)	H5'···Cl^viii	3.14 (3)
C3···C1^x	3.467 (3)	H5"···Cl^vii	2.28 (4)
C1—N—H5'	109.4 (18)	C2—C4—C3^i	120.5 (2)
C1—N—H5"	107 (2)	N—C1—H1	107.8 (17)
H5—N—H5'	113 (3)	N—C1—H1'	104.9 (18)
H5—N—H5"	105 (3)	C2—C1—H1	110.1 (17)
H5'—N—H5"	112 (3)	C2—C1—H1'	111.9 (18)
C1—N—H5	111.4 (18)	H1—C1—H1'	110 (2)
N—C1—C2	111.66 (18)	C2—C3—H3	118.1 (18)
C1—C2—C3	121.1 (2)	C4^i—C3—H3	121.7 (18)
C1—C2—C4	119.7 (2)	C2—C4—H4	119.5 (17)
C3—C2—C4	119.27 (19)	C3^i—C4—H4	120.0 (17)
C2—C3—C4^i	120.3 (2)
N—C1—C2—C3	−80.4 (3)	C1—C2—C4—C3^i	178.8 (2)
N—C1—C2—C4	101.2 (2)	C3—C2—C4—C3^i	0.4 (3)
C1—C2—C3—C4^i	−178.8 (2)	C2—C3—C4^i—C2^i	0.4 (3)
C4—C2—C3—C4^i	−0.4 (3)

Symmetry codes: (i) −x+1, −y, −z+1; (ii) −x+1, −y+1, −z+1; (iii) x, y, z−1; (iv) x−1, y, z−1; (v) −x, −y+1, −z+1; (vi) −x, −y, −z+1; (vii) x, y, z+1; (viii) x+1, y, z+1; (ix) x−1, y, z; (x) x+1, y, z; (xi) x, y−1, z; (xii) x, y+1, z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N—H5···Cl^ii	0.92 (3)	2.32 (3)	3.190 (2)	158 (3)
N—H5′···Cl^i	0.92 (3)	2.32 (3)	3.235 (2)	176 (2)
N—H5"···Cl^vii	0.93 (4)	2.28 (4)	3.199 (2)	175 (4)
C1—H1···Cl^vi	0.98 (3)	2.80 (3)	3.705 (2)	154 (2)

Symmetry codes: (i) −x+1, −y, −z+1; (ii) −x+1, −y+1, −z+1; (vi) −x, −y, −z+1; (vii) x, y, z+1.