Bis­(di­methyl­ammonium) terephthalate

The asymmetric unit of the title compound, 2C₂H₈N⁺·C₈H₄O₄²⁻, comprises two crystallographically independent dimethylammonium cations and two half-terephthalate anions. The latter are each disposed about an inversion centre. N—H...O hydrogen bonds link the ions into a three-dimensional framework.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.053
• wR factor = 0.134
• Data-to-parameter ratio = 15.2

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT242_ALERT_2_B Check Low    U(eq) as Compared to Neighbors  for         N1

Alert level C
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT242_ALERT_2_C Check Low    U(eq) as Compared to Neighbors  for         N2
PLAT353_ALERT_3_C Long    N-H Bond (0.87A)   N2     -   H2     ...       1.02 Ang.

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

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 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

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Computing details

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (2000); software used to prepare material for publication: WinGX (Farrugia, 1999).

bis(dimethylammonium) terephtalate

Crystal data

2C2H8N^+·C8H4O4^2^−	F(000) = 552
Mr = 256.30	Dx = 1.198 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 20 reflections
a = 9.642 (2) Å	θ = 10–14°
b = 11.103 (2) Å	µ = 0.09 mm^−1
c = 13.272 (3) Å	T = 293 K
β = 91.01 (3)°	Prism, colourless
V = 1420.6 (5) Å^3	0.5 × 0.3 × 0.2 mm
Z = 4

Data collection

Enraf–Nonius CAD-4 diffractometer	1759 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.050
Graphite monochromator	θmax = 26.0°, θmin = 2.4°
non–profiled ω scans	h = −11→11
Absorption correction: ψ scan (North et al., 1968)	k = 0→13
Tmin = 0.968, Tmax = 0.982	l = 0→16
2910 measured reflections	2 standard reflections every 7200 min
2790 independent reflections	intensity decay: 1%

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.053	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.134	w = 1/[σ^2(Fo^2) + (0.0626P)^2 + 0.1137P] where P = (Fo^2 + 2Fc^2)/3
S = 1.05	(Δ/σ)max = 0.001
2790 reflections	Δρmax = 0.20 e Å^−3
184 parameters	Δρmin = −0.23 e Å^−3
1 restraint	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.083 (7)

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
O1	0.16949 (16)	0.32520 (16)	0.30168 (11)	0.0503 (5)
O2	0.32915 (15)	0.37168 (15)	0.41691 (12)	0.0518 (5)
O3	−0.23902 (17)	0.18343 (17)	0.34577 (14)	0.0607 (5)
O4	−0.35178 (17)	0.12149 (19)	0.47936 (13)	0.0697 (6)
N1	0.4891 (2)	0.23523 (19)	0.29320 (14)	0.0428 (5)
N2	0.0194 (2)	0.2716 (2)	0.13398 (17)	0.0504 (6)
C1	0.0995 (2)	0.43806 (18)	0.44428 (14)	0.0315 (5)
C2	0.2069 (2)	0.37309 (19)	0.38263 (15)	0.0349 (5)
C3	0.1391 (2)	0.51530 (19)	0.52135 (15)	0.0376 (5)
H3	0.2329	0.5263	0.5362	0.045*
C4	0.0413 (2)	0.5763 (2)	0.57671 (15)	0.0368 (5)
H4	0.0700	0.6275	0.6285	0.044*
C5	−0.2453 (2)	0.1282 (2)	0.42708 (17)	0.0432 (6)
C6	−0.1171 (2)	0.06183 (19)	0.46475 (14)	0.0337 (5)
C7	0.0122 (2)	0.0890 (2)	0.42851 (16)	0.0395 (5)
H7	0.0215	0.1491	0.3802	0.047*
C8	−0.1276 (2)	−0.0281 (2)	0.53679 (15)	0.0394 (5)
H8	−0.2141	−0.0475	0.5620	0.047*
C9	0.4241 (3)	0.1145 (2)	0.2916 (2)	0.0625 (7)
H9A	0.3284	0.1217	0.2713	0.094*
H9B	0.4302	0.0797	0.3578	0.094*
H9C	0.4715	0.0639	0.2448	0.094*
C10	0.4904 (3)	0.2906 (3)	0.1931 (2)	0.0892 (11)
H10A	0.5402	0.2397	0.1478	0.134*
H10B	0.5350	0.3678	0.1973	0.134*
H10C	0.3968	0.3006	0.1686	0.134*
C11	−0.1256 (3)	0.3116 (3)	0.1309 (2)	0.0654 (8)
H11A	−0.1704	0.2817	0.0708	0.098*
H11B	−0.1289	0.3980	0.1311	0.098*
H11C	−0.1725	0.2811	0.1889	0.098*
C12	0.0327 (4)	0.1401 (3)	0.1284 (2)	0.0873 (11)
H12A	−0.0112	0.1042	0.1854	0.131*
H12B	0.1291	0.1185	0.1287	0.131*
H12C	−0.0112	0.1115	0.0675	0.131*
H1	0.063 (3)	0.302 (2)	0.193 (2)	0.072 (9)*
H2	0.069 (3)	0.311 (3)	0.075 (2)	0.091 (10)*
H5	0.5818 (18)	0.229 (2)	0.3170 (17)	0.055 (7)*
H6	0.441 (3)	0.287 (2)	0.338 (2)	0.076 (9)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0443 (9)	0.0688 (11)	0.0377 (9)	0.0084 (8)	−0.0023 (7)	−0.0173 (8)
O2	0.0370 (9)	0.0671 (12)	0.0511 (9)	0.0134 (8)	−0.0057 (7)	−0.0177 (8)
O3	0.0443 (10)	0.0714 (13)	0.0660 (11)	0.0039 (9)	−0.0115 (8)	0.0238 (10)
O4	0.0439 (10)	0.1062 (16)	0.0591 (11)	0.0286 (10)	0.0056 (9)	−0.0001 (10)
N1	0.0350 (10)	0.0519 (13)	0.0415 (11)	0.0100 (9)	0.0007 (8)	0.0033 (9)
N2	0.0489 (12)	0.0621 (14)	0.0400 (12)	−0.0020 (10)	−0.0062 (10)	−0.0033 (10)
C1	0.0323 (10)	0.0317 (11)	0.0303 (10)	0.0027 (9)	0.0007 (8)	0.0015 (9)
C2	0.0376 (11)	0.0352 (12)	0.0319 (11)	0.0035 (9)	−0.0012 (9)	0.0012 (9)
C3	0.0288 (10)	0.0441 (13)	0.0396 (12)	−0.0013 (9)	−0.0011 (9)	−0.0034 (10)
C4	0.0368 (11)	0.0401 (12)	0.0333 (11)	−0.0002 (10)	−0.0019 (9)	−0.0070 (10)
C5	0.0410 (13)	0.0447 (13)	0.0436 (13)	0.0039 (10)	−0.0067 (11)	−0.0061 (11)
C6	0.0315 (10)	0.0383 (12)	0.0311 (10)	0.0006 (9)	−0.0025 (8)	−0.0053 (9)
C7	0.0426 (13)	0.0410 (13)	0.0350 (11)	−0.0030 (10)	0.0005 (9)	0.0065 (10)
C8	0.0278 (10)	0.0531 (14)	0.0373 (11)	−0.0054 (10)	0.0042 (9)	0.0008 (10)
C9	0.0501 (15)	0.0611 (18)	0.0760 (18)	0.0013 (13)	−0.0032 (13)	−0.0112 (14)
C10	0.073 (2)	0.127 (3)	0.0679 (19)	0.022 (2)	0.0125 (16)	0.051 (2)
C11	0.0483 (15)	0.086 (2)	0.0621 (17)	0.0076 (14)	−0.0070 (13)	−0.0018 (15)
C12	0.115 (3)	0.074 (2)	0.073 (2)	0.0221 (19)	−0.0329 (19)	−0.0171 (17)

Geometric parameters (Å, º)

O1—C2	1.246 (2)	C5—C6	1.516 (3)
O2—C2	1.256 (2)	C6—C7	1.378 (3)
O3—C5	1.244 (3)	C6—C8	1.388 (3)
O4—C5	1.252 (3)	C7—C8^ii	1.374 (3)
N1—C10	1.464 (3)	C7—H7	0.9300
N1—C9	1.480 (3)	C8—H8	0.9300
N1—H5	0.946 (16)	C9—H9A	0.9600
N1—H6	0.96 (3)	C9—H9B	0.9600
N2—C11	1.467 (3)	C9—H9C	0.9600
N2—C12	1.468 (4)	C10—H10A	0.9600
N2—H1	0.95 (3)	C10—H10B	0.9600
N2—H2	1.02 (3)	C10—H10C	0.9600
C1—C3	1.383 (3)	C11—H11A	0.9600
C1—C4^i	1.390 (3)	C11—H11B	0.9600
C1—C2	1.514 (3)	C11—H11C	0.9600
C3—C4	1.383 (3)	C12—H12A	0.9600
C3—H3	0.9300	C12—H12B	0.9600
C4—H4	0.9300	C12—H12C	0.9600
C10—N1—C9	112.2 (2)	C8^ii—C7—C6	120.5 (2)
C10—N1—H5	108.2 (15)	C8^ii—C7—H7	119.8
C9—N1—H5	109.5 (14)	C6—C7—H7	119.8
C10—N1—H6	109.0 (17)	C7^ii—C8—C6	121.12 (19)
C9—N1—H6	110.2 (16)	C7^ii—C8—H8	119.4
H5—N1—H6	108 (2)	C6—C8—H8	119.4
C11—N2—C12	112.5 (2)	N1—C9—H9A	109.5
C11—N2—H1	109.0 (17)	N1—C9—H9B	109.5
C12—N2—H1	111.3 (16)	H9A—C9—H9B	109.5
C11—N2—H2	107.9 (17)	N1—C9—H9C	109.5
C12—N2—H2	110.3 (18)	H9A—C9—H9C	109.5
H1—N2—H2	105 (2)	H9B—C9—H9C	109.5
C3—C1—C4^i	118.36 (18)	N1—C10—H10A	109.5
C3—C1—C2	120.85 (18)	N1—C10—H10B	109.5
C4^i—C1—C2	120.77 (18)	H10A—C10—H10B	109.5
O1—C2—O2	124.20 (19)	N1—C10—H10C	109.5
O1—C2—C1	118.64 (18)	H10A—C10—H10C	109.5
O2—C2—C1	117.16 (18)	H10B—C10—H10C	109.5
C4—C3—C1	120.99 (18)	N2—C11—H11A	109.5
C4—C3—H3	119.5	N2—C11—H11B	109.5
C1—C3—H3	119.5	H11A—C11—H11B	109.5
C3—C4—C1^i	120.67 (18)	N2—C11—H11C	109.5
C3—C4—H4	119.7	H11A—C11—H11C	109.5
C1^i—C4—H4	119.7	H11B—C11—H11C	109.5
O3—C5—O4	124.3 (2)	N2—C12—H12A	109.5
O3—C5—C6	118.3 (2)	N2—C12—H12B	109.5
O4—C5—C6	117.4 (2)	H12A—C12—H12B	109.5
C7—C6—C8	118.41 (19)	N2—C12—H12C	109.5
C7—C6—C5	121.04 (19)	H12A—C12—H12C	109.5
C8—C6—C5	120.54 (19)	H12B—C12—H12C	109.5

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H5···O3^iii	0.95 (2)	1.83 (2)	2.761 (3)	167 (2)
N1—H6···O2	0.96 (3)	1.78 (3)	2.731 (3)	171 (2)
N2—H1···O1	0.95 (3)	1.77 (3)	2.700 (3)	165 (2)
N2—H2···O4^iv	1.02 (3)	1.68 (3)	2.693 (3)	179 (3)

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