Butane-1,4-diammonium dibromide

The crystal structure of butane-1,4-diammonium dibromide, C₄H₁₄N₂²⁺·2Br^-, exhibits ionic-inorganic layers separated by organic hydro­carbon layers. The organic hydro­carbon layers pack in a stacked herring-bone manner with hydrogen bonds to the bromide ions. The cation sits on a centre of inversion. The structure is compared with that of butane-1,4-diammonium dichloride and butane-1,4-diammonium diiodide.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.006 Å
• R factor = 0.045
• wR factor = 0.131
• Data-to-parameter ratio = 28.5

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT480_ALERT_4_B Long H...A H-Bond Reported H1C    ..  BR1     ..       3.32 Ang.
PLAT480_ALERT_4_B Long H...A H-Bond Reported H1E    ..  BR1     ..       3.33 Ang.
PLAT482_ALERT_4_B Small D-H..A Angle Rep for N1     ..  BR1     ..      87.10 Deg.
PLAT482_ALERT_4_B Small D-H..A Angle Rep for N1     ..  BR1     ..      86.30 Deg.

Alert level C
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.44
PLAT480_ALERT_4_C Long H...A H-Bond Reported H1D    ..  BR1     ..       2.99 Ang.

Alert level G
ABSTM02_ALERT_3_G  When printed, the submitted absorption T values will be
            replaced by the scaled T values. Since the ratio of scaled T's
            is identical to the ratio of reported T values, the scaling
            does not imply a change to the absorption corrections used in
            the study.
            Ratio of Tmax expected/reported      0.435
            Tmax scaled      0.083 Tmin scaled      0.024
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        293 K

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

   3 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
   6 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, 1998); cell refinement: SAINT-Plus (Bruker, 1999); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and Mercury (Bruno et al., 2002); software used to prepare material for publication: WinGX (Farrugia, 1999), PLATON (Spek, 2003) and pubICIF (Westrip, 2006).

Butane-1,4-diammonium dibromide

Crystal data

C4H14N2^2+·2Br^−	F(000) = 244
Mr = 249.99	Dx = 1.839 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 669 reflections
a = 4.7107 (9) Å	θ = 3.0–28.3°
b = 8.5491 (15) Å	µ = 8.90 mm^−1
c = 11.229 (2) Å	T = 293 K
β = 93.037 (4)°	Block, colourless
V = 451.57 (14) Å^3	0.44 × 0.30 × 0.28 mm
Z = 2

Data collection

Bruker SMART CCD area-detector diffractometer	1113 independent reflections
Radiation source: fine-focus sealed tube	942 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.024
φ and ω scans	θmax = 28.3°, θmin = 3.0°
Absorption correction: multi-scan (SADABS; Sheldrick, 2004)	h = −6→6
Tmin = 0.056, Tmax = 0.190	k = −6→11
2321 measured reflections	l = −11→14

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.045	H-atom parameters constrained
wR(F^2) = 0.131	w = 1/[σ^2(Fo^2) + (0.0984P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 0.99	(Δ/σ)max < 0.001
1113 reflections	Δρmax = 1.50 e Å^−3
39 parameters	Δρmin = −1.64 e Å^−3
0 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.45 (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
C1	0.5747 (8)	0.3000 (4)	0.5718 (4)	0.0324 (8)
H1A	0.6773	0.2556	0.5073	0.039*
H1B	0.7129	0.3337	0.6337	0.039*
C2	0.4044 (9)	0.4393 (5)	0.5263 (4)	0.0331 (9)
H2A	0.3059	0.4855	0.5913	0.040*
H2B	0.2630	0.4053	0.4659	0.040*
N1	0.3869 (8)	0.1784 (4)	0.6208 (4)	0.0366 (8)
H1C	0.4915	0.0970	0.6459	0.055*
H1D	0.2600	0.1475	0.5641	0.055*
H1E	0.2971	0.2181	0.6817	0.055*
Br1	0.11369 (9)	0.09905 (4)	0.33855 (4)	0.0370 (3)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0310 (18)	0.0311 (18)	0.035 (2)	0.0005 (15)	0.0007 (15)	0.0005 (16)
C2	0.035 (2)	0.0295 (17)	0.035 (2)	0.0013 (16)	0.0034 (16)	0.0034 (16)
N1	0.0414 (19)	0.0280 (16)	0.0407 (19)	−0.0001 (14)	0.0041 (14)	0.0020 (14)
Br1	0.0416 (4)	0.0366 (4)	0.0327 (4)	−0.00146 (15)	0.0021 (2)	0.00391 (14)

Geometric parameters (Å, º)

C1—N1	1.489 (5)	C2—H2A	0.970
C1—C2	1.510 (5)	C2—H2B	0.970
C1—H1A	0.970	N1—H1C	0.890
C1—H1B	0.970	N1—H1D	0.890
C2—C2^i	1.514 (8)	N1—H1E	0.890
N1—C1—C2	111.1 (3)	C1—C2—H2B	109.5
N1—C1—H1A	109.4	C2^i—C2—H2B	109.5
C2—C1—H1A	109.4	H2A—C2—H2B	108.1
N1—C1—H1B	109.4	C1—N1—H1C	109.5
C2—C1—H1B	109.4	C1—N1—H1D	109.5
H1A—C1—H1B	108.0	H1C—N1—H1D	109.5
C1—C2—C2^i	110.9 (4)	C1—N1—H1E	109.5
C1—C2—H2A	109.5	H1C—N1—H1E	109.5
C2^i—C2—H2A	109.5	H1D—N1—H1E	109.5
N1—C1—C2—C2^i	−178.5 (4)

Symmetry code: (i) −x+1, −y+1, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1C···Br1^ii	0.89	2.50	3.355 (4)	161
N1—H1D···Br1	0.89	2.62	3.425 (4)	150
N1—H1E···Br1^iii	0.89	2.54	3.404 (4)	164
N1—H1C···Br1^iv	0.89	3.32	3.393 (3)	87
N1—H1D···Br1^iv	0.89	2.99	3.393 (3)	110
N1—H1E···Br1^iv	0.89	3.33	3.393 (3)	86

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