4-Methyl­anilinium nitrate

In the crystal structure of the title compound, C₇H₁₀N⁺·NO₃⁻, N—H...O hydrogen bonds involving the ammonium group and the nitrate O atoms result in the formation of zigzag chains propagating in [100].

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.057
• wR factor = 0.156
• Data-to-parameter ratio = 18.1

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT230_ALERT_2_B Hirshfeld Test Diff for    C3     --  C4      ..      18.38 su
PLAT926_ALERT_1_B Reported and Calculated   R1 * 100.0 Differ by .      -1.49
PLAT927_ALERT_1_B Reported and Calculated  wR2 * 100.0 Differ by .      -4.73
PLAT928_ALERT_1_B Reported and Calculated    S value   Differ by .      -0.31

Alert level C
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         N2
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          2
PLAT912_ALERT_4_C Missing # of FCF Reflections Above STh/L=  0.600          2

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

   3 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
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

As a part of systematic investigation of dielectric-ferroelectric materials, including organic ligands (Li et al., 2008), metal–organic coordination compounds (Hang et al., 2009), we have found that 4-methylbenzenaminium nitrate has no dielectric disuniform from 80 K to 445 K, (m.p. 465–468 K). Herein we descibe the crystal structure of this compound.

The asymmetric unit of the title compound consists of a 4-methylbenzenaminium cation and a nitrate anion (Fig. 1).

In the crystal N—H···O hydrogen bonds (Table 1) link the cations and anions to form chains propagating along the a axis (Fig 2).

Related literature

For dielectric-ferroelectric materials, including organic ligands and metal-organic coordination compounds, see: Hang et al. (2009); Li et al. (2008).

S2. Experimental

The title compound was obtained by mixing p-toluidine and nitric acid in ethanol, in the stoichiometric ratio 1:1. After a few weeks, colorless crystals were obtained by slow evaporation.

S3. Refinement

The H atoms were included in calculated postions and treated as riding atoms: N—H = 0.89 Å, aromatic C—H = 0.93 Å, methyl C—H = 0.96 Å, with U_iso(H) = k × U_eq(parent N- or C-atom), where k = 1.2 for aromatic H atoms, and 1.5 for amonium and methyl H atoms.

Computing details

Data collection: CrystalClear (Rigaku, 2005); cell refinement: CrystalClear (Rigaku, 2005); data reduction: CrystalClear (Rigaku, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: PRPKAPPA (Ferguson, 1999).

Figures

	Fig. 1. The molecular structure of the title compound, showing the atomic numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.
	Fig. 2. A view of the crystal packing of the title compound. The N—H···O hydrogen bonds are shown as dashed lines (see Table 1 for details).

4-Methylanilinium nitrate

Crystal data

C7H10N^+·NO3^−	F(000) = 360
Mr = 170.17	Dx = 1.295 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3553 reflections
a = 5.6468 (11) Å	θ = 3.3–27.6°
b = 8.7860 (18) Å	µ = 0.10 mm^−1
c = 17.811 (4) Å	T = 298 K
β = 99.01 (3)°	Prism, colourless
V = 872.8 (3) Å^3	0.60 × 0.40 × 0.40 mm
Z = 4

Data collection

Rigaku Mercury2 diffractometer	2011 independent reflections
Radiation source: fine-focus sealed tube	1432 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.038
Detector resolution: 13.6612 pixels mm^-1	θmax = 27.5°, θmin = 3.3°
CCD profile fitting scans	h = −7→7
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)	k = −11→11
Tmin = 0.5, Tmax = 0.5	l = −23→23
8641 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.057	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.156	H-atom parameters constrained
S = 1.01	w = 1/[σ^2(Fo^2) + (0.0752P)^2 + 0.2152P] where P = (Fo^2 + 2Fc^2)/3
2011 reflections	(Δ/σ)max < 0.001
111 parameters	Δρmax = 0.24 e Å^−3
0 restraints	Δρmin = −0.26 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 esds 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
N1	0.3877 (3)	0.91687 (17)	0.33271 (9)	0.0512 (5)
C1	0.4679 (3)	0.83868 (18)	0.40462 (10)	0.0434 (5)
C2	0.6763 (3)	0.7554 (2)	0.41229 (12)	0.0658 (8)
C3	0.7515 (4)	0.6808 (2)	0.47979 (14)	0.0578 (7)
C4	0.6214 (4)	0.6858 (2)	0.53968 (12)	0.0607 (7)
C5	0.4132 (4)	0.7703 (2)	0.52945 (11)	0.0627 (7)
C6	0.3354 (3)	0.8472 (2)	0.46280 (11)	0.0542 (6)
C7	0.7061 (5)	0.6011 (3)	0.61266 (14)	0.0920 (10)
O1	0.9140 (3)	0.02956 (19)	0.33081 (10)	0.0803 (6)
O2	0.6445 (2)	0.17377 (18)	0.27222 (9)	0.0675 (5)
O3	0.9986 (3)	0.1724 (2)	0.24110 (9)	0.0737 (6)
N2	0.8567 (3)	0.12615 (18)	0.28068 (9)	0.0492 (5)
H1A	0.49500	0.98720	0.32520	0.0770*
H1B	0.24690	0.96120	0.33430	0.0770*
H1C	0.37240	0.84980	0.29480	0.0770*
H2	0.76490	0.74950	0.37260	0.0690*
H3	0.89360	0.62550	0.48540	0.0790*
H5	0.32260	0.77550	0.56870	0.0750*
H6	0.19500	0.90420	0.45730	0.0650*
H7A	0.57120	0.55570	0.63080	0.1380*
H7B	0.78420	0.67070	0.65010	0.1380*
H7C	0.81700	0.52300	0.60350	0.1380*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.0498 (9)	0.0510 (9)	0.0537 (9)	−0.0069 (7)	0.0109 (7)	0.0010 (7)
C1	0.0431 (9)	0.0401 (9)	0.0470 (9)	−0.0087 (7)	0.0073 (7)	−0.0034 (7)
C2	0.0571 (12)	0.0555 (12)	0.0831 (15)	0.0059 (9)	0.0053 (11)	0.0088 (11)
C3	0.0526 (11)	0.0544 (11)	0.0700 (13)	0.0012 (9)	0.0206 (9)	0.0022 (9)
C4	0.0764 (14)	0.0453 (10)	0.0553 (11)	−0.0150 (10)	−0.0054 (10)	−0.0008 (8)
C5	0.0785 (14)	0.0653 (13)	0.0467 (11)	−0.0118 (11)	0.0175 (10)	−0.0070 (9)
C6	0.0521 (10)	0.0564 (11)	0.0555 (11)	0.0007 (9)	0.0126 (8)	−0.0059 (9)
C7	0.128 (2)	0.0688 (15)	0.0681 (15)	−0.0148 (15)	−0.0194 (15)	0.0106 (12)
O1	0.0720 (10)	0.0797 (10)	0.0930 (12)	0.0197 (8)	0.0244 (9)	0.0394 (9)
O2	0.0512 (8)	0.0811 (10)	0.0718 (10)	0.0102 (7)	0.0143 (7)	0.0174 (8)
O3	0.0618 (9)	0.0937 (12)	0.0703 (10)	−0.0148 (8)	0.0253 (7)	0.0113 (8)
N2	0.0489 (8)	0.0516 (8)	0.0478 (8)	−0.0026 (7)	0.0098 (6)	−0.0004 (7)

Geometric parameters (Å, º)

O1—N2	1.238 (2)	C4—C5	1.378 (3)
O2—N2	1.256 (2)	C4—C7	1.509 (3)
O3—N2	1.217 (2)	C5—C6	1.377 (3)
N1—C1	1.461 (2)	C2—H2	0.9300
N1—H1A	0.8900	C3—H3	0.9300
N1—H1B	0.8900	C5—H5	0.9300
N1—H1C	0.8900	C6—H6	0.9300
C1—C6	1.372 (3)	C7—H7A	0.9600
C1—C2	1.374 (2)	C7—H7B	0.9600
C2—C3	1.377 (3)	C7—H7C	0.9600
C3—C4	1.387 (3)
H1B—N1—H1C	109.00	C4—C5—C6	121.92 (19)
C1—N1—H1B	109.00	C1—C6—C5	119.10 (17)
C1—N1—H1C	109.00	C3—C2—H2	121.00
C1—N1—H1A	109.00	C1—C2—H2	121.00
H1A—N1—H1C	109.00	C4—C3—H3	119.00
H1A—N1—H1B	109.00	C2—C3—H3	119.00
O1—N2—O2	116.86 (17)	C4—C5—H5	119.00
O2—N2—O3	121.45 (17)	C6—C5—H5	119.00
O1—N2—O3	121.70 (18)	C1—C6—H6	120.00
C2—C1—C6	120.92 (17)	C5—C6—H6	120.00
N1—C1—C6	120.37 (16)	C4—C7—H7C	109.00
N1—C1—C2	118.71 (17)	H7A—C7—H7C	109.00
C1—C2—C3	118.85 (19)	H7B—C7—H7C	109.00
C2—C3—C4	121.9 (2)	H7A—C7—H7B	109.00
C3—C4—C5	117.31 (19)	C4—C7—H7A	109.00
C3—C4—C7	120.8 (2)	C4—C7—H7B	109.00
C5—C4—C7	121.9 (2)
N1—C1—C2—C3	−179.58 (16)	C2—C3—C4—C5	−0.7 (3)
C6—C1—C2—C3	−0.4 (3)	C2—C3—C4—C7	179.1 (2)
N1—C1—C6—C5	178.92 (16)	C3—C4—C5—C6	0.0 (3)
C2—C1—C6—C5	−0.3 (3)	C7—C4—C5—C6	−179.8 (2)
C1—C2—C3—C4	0.9 (3)	C4—C5—C6—C1	0.5 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O1^i	0.89	2.38	3.138 (3)	143
N1—H1A···O2^i	0.89	2.13	2.975 (2)	158
N1—H1B···O1^ii	0.89	1.97	2.848 (2)	171
N1—H1C···O2^iii	0.89	1.95	2.825 (2)	169

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