PMCCPMCCPMCC

Search tips
Search criteria 

Advanced

 
Logo of actaeInternational Union of Crystallographysearchopen accessarticle submissionjournal home pagethis article
 
Acta Crystallogr Sect E Struct Rep Online. 2010 July 1; 66(Pt 7): o1865.
Published online 2010 June 30. doi:  10.1107/S1600536810024840
PMCID: PMC3006843

p-Phenyl­enedimethanaminium dibromide

Abstract

In the title salt, C8H14N2 2+·2Br, the cation has a crystallographically imposed centre of symmetry. The compound is isostructural with the chloride analogue. In the crystal structure, the cations and anions are connected via N—H(...)Br hydrogen bonds, forming layers parallel to the bc plane.

Related literature

For the synthesis, structures and properties of ferroelectric organic or inorganic compounds, see: Haertling (1999 [triangle]); Homes et al. (2001 [triangle]); Fu et al. (2009 [triangle]); Hang et al. (2009 [triangle]). For the structure of the isostructural chloride salt, see: Arkenbout et al. (2007 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-o1865-scheme1.jpg

Experimental

Crystal data

  • C8H14N2 2+·2Br
  • M r = 298.01
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o1865-efi1.jpg
  • a = 4.4462 (9) Å
  • b = 6.0331 (12) Å
  • c = 10.347 (2) Å
  • α = 101.90 (3)°
  • β = 99.79 (3)°
  • γ = 94.29 (3)°
  • V = 265.89 (9) Å3
  • Z = 1
  • Mo Kα radiation
  • μ = 7.58 mm−1
  • T = 293 K
  • 0.20 × 0.20 × 0.20 mm

Data collection

  • Rigaku Mercury2 diffractometer
  • Absorption correction: multi-scan (CrystalClear; Rigaku, 2005 [triangle]) T min = 0.837, T max = 1.000
  • 2767 measured reflections
  • 1213 independent reflections
  • 1107 reflections with I > 2σ(I)
  • R int = 0.053

Refinement

  • R[F 2 > 2σ(F 2)] = 0.034
  • wR(F 2) = 0.084
  • S = 1.10
  • 1213 reflections
  • 56 parameters
  • H-atom parameters constrained
  • Δρmax = 0.59 e Å−3
  • Δρmin = −0.68 e Å−3

Data collection: CrystalClear (Rigaku, 2005 [triangle]); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: SHELXTL/PC (Sheldrick, 2008 [triangle]); software used to prepare material for publication: SHELXTL/PC.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810024840/rz2469sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810024840/rz2469Isup2.hkl

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

Acknowledgments

The authors are grateful to the Starter Fund of Southeast University for financial support to buy the X-ray diffractometer.

supplementary crystallographic information

Comment

At present, much attention in ferroelectric material field is focused on developing ferroelectric pure organic or inorganic compounds (Haertling, 1999; Homes et al., 2001). Recently we have reported the synthesis of a variety of compounds (Fu et al., 2009; Hang et al., 2009), which have potential piezoelectric and ferroelectric properties. In order to develop new materials of this kind, we investigated the physical properties of the title compound. Its dielectric constant as a function of temperature (93-440 K) indicates that the permittivity is basically temperature-independent (dielectric constant ranging from 3.2 to 4.4), suggesting that this compound should be not a real ferroelectrics or that no distinct phase transition occurred within the measured temperature range. Herein, we report the synthesis and crystal structure of the title compound (Fig. 1).

The cation of the title compound possesses crystallographically imposed centre of symmetry. The compound is isostructural to the chloride analogue (Arkenbout et al., 2007). Bond lengths and angles are within their normal ranges. In the crystal packing (Fig. 2), cations and anions are connected via intermolecular N—H···Br hydrogen bonds (Table 1) to form layers parallel to the bc plane. Contrary to what observed in the chloride salt, the separation between the centroids of stacked aromatic rings (4.446 (2) Å) suggests that no π···π stacking interactions are present.

Experimental

Hydrobromic acid (4.05 g, 40%) was added slowly to a solution of 1,4-phenylenedimethanamine (2.72 g, 0.02 mol) in methanol. After several days, colourless prismatic crystals of the title compound suitable for X-ray analysis were obtained on slow evaporation of the solvent.

Refinement

H atoms were positioned geometrically and refined using a riding model, with C—H = 0.93-0.97 Å, N—H = 0.89 Å, and with Uiso(H) = 1.2eq(C, N).

Figures

Fig. 1.
The structure of the title compound showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. Atoms labelled with the suffix A are related by the symmetry code (1-x, 1-y, 1-z).
Fig. 2.
Crystal packing of the title compound approximately viewed along the b axis, showing the hydrogen bondings network.

Crystal data

C8H14N22+·2BrZ = 1
Mr = 298.01F(000) = 146
Triclinic, P1Dx = 1.861 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 4.4462 (9) ÅCell parameters from 1213 reflections
b = 6.0331 (12) Åθ = 2.6–27.5°
c = 10.347 (2) ŵ = 7.58 mm1
α = 101.90 (3)°T = 293 K
β = 99.79 (3)°Prism, colorless
γ = 94.29 (3)°0.20 × 0.20 × 0.20 mm
V = 265.89 (9) Å3

Data collection

Rigaku Mercury2 diffractometer1213 independent reflections
Radiation source: fine-focus sealed tube1107 reflections with I > 2σ(I)
graphiteRint = 0.053
Detector resolution: 13.6612 pixels mm-1θmax = 27.5°, θmin = 3.5°
CCD_Profile_fitting scansh = −5→5
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)k = −7→7
Tmin = 0.837, Tmax = 1.000l = −13→13
2767 measured reflections

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.034H-atom parameters constrained
wR(F2) = 0.084w = 1/[σ2(Fo2) + (0.0314P)2] where P = (Fo2 + 2Fc2)/3
S = 1.10(Δ/σ)max < 0.001
1213 reflectionsΔρmax = 0.59 e Å3
56 parametersΔρmin = −0.68 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.102 (8)

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 (Å2)

xyzUiso*/Ueq
N10.5050 (7)0.6880 (4)0.8667 (3)0.0352 (6)
H1A0.42700.73940.93930.042*
H1B0.66280.78450.86460.042*
H1C0.56680.55250.86980.042*
C20.2679 (7)0.6652 (6)0.7437 (3)0.0354 (8)
H2D0.19430.81210.74170.042*
H2E0.09520.55930.74660.042*
C50.3474 (8)0.3493 (5)0.5579 (3)0.0345 (7)
H5A0.24470.24760.59650.041*
C70.3911 (7)0.5816 (5)0.6174 (3)0.0293 (7)
C100.4567 (8)0.2702 (6)0.4418 (3)0.0353 (8)
H10A0.42760.11500.40280.042*
Br1−0.14338 (7)0.20342 (5)0.87105 (3)0.03667 (19)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
N10.0523 (17)0.0363 (15)0.0199 (14)0.0134 (12)0.0156 (11)0.0027 (12)
C20.0390 (17)0.0412 (19)0.0265 (17)0.0107 (14)0.0140 (13)0.0005 (15)
C50.0451 (18)0.0314 (17)0.0300 (19)0.0020 (13)0.0145 (14)0.0088 (15)
C70.0343 (16)0.0345 (17)0.0197 (16)0.0071 (12)0.0074 (12)0.0040 (14)
C100.055 (2)0.0265 (16)0.0249 (18)0.0067 (14)0.0131 (15)0.0013 (14)
Br10.0478 (3)0.0329 (3)0.0303 (3)0.00763 (15)0.01254 (16)0.00384 (18)

Geometric parameters (Å, °)

N1—C21.483 (4)C5—C101.380 (4)
N1—H1A0.8880C5—C71.394 (4)
N1—H1B0.8839C5—H5A0.9300
N1—H1C0.8865C7—C10i1.382 (5)
C2—C71.509 (4)C10—C7i1.382 (5)
C2—H2D0.9700C10—H10A0.9300
C2—H2E0.9700
C2—N1—H1A109.9H2D—C2—H2E107.9
C2—N1—H1B109.6C10—C5—C7120.0 (3)
H1A—N1—H1B109.3C10—C5—H5A120.0
C2—N1—H1C109.0C7—C5—H5A120.0
H1A—N1—H1C109.4C10i—C7—C5119.1 (3)
H1B—N1—H1C109.6C10i—C7—C2121.7 (3)
N1—C2—C7111.9 (2)C5—C7—C2119.3 (3)
N1—C2—H2D109.2C5—C10—C7i120.9 (3)
C7—C2—H2D109.2C5—C10—H10A119.5
N1—C2—H2E109.2C7i—C10—H10A119.5
C7—C2—H2E109.2

Symmetry codes: (i) −x+1, −y+1, −z+1.

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N1—H1A···Br1ii0.892.493.359 (3)167
N1—H1B···Br1iii0.882.593.363 (3)146
N1—H1C···Br1iv0.892.553.422 (3)167

Symmetry codes: (ii) −x, −y+1, −z+2; (iii) x+1, y+1, z; (iv) x+1, y, z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: RZ2469).

References

  • Arkenbout, A. H., Meetsma, A. & Palstra, T. T. M. (2007). Acta Cryst. E63, o869–o870.
  • Fu, D. W., Ge, J. Z., Dai, J., Ye, H. Y. & Qu, Z. R. (2009). Inorg. Chem. Commun.12, 994–997.
  • Haertling, G. H. (1999). J. Am. Ceram. Soc.82, 797–810.
  • Hang, T., Fu, D. W., Ye, Q. & Xiong, R. G. (2009). Cryst. Growth Des.5, 2026–2029.
  • Homes, C. C., Vogt, T., Shapiro, S. M., Wakimoto, S. & Ramirez, A. P. (2001). Science, 293, 673–676. [PubMed]
  • Rigaku (2005). CrystalClear Rigaku Corporation, Tokyo, Japan.
  • Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. [PubMed]

Articles from Acta Crystallographica Section E: Structure Reports Online are provided here courtesy of International Union of Crystallography