Ammonium dicyano­(cyano­acet­yl)methanide: one condensation product of malononitrile

The title compound, NH₄⁺·C₆H₂N₃O⁻, was obtained as a secondary product in a reaction of squaric acid and excess malononitrile (1:20). The crystal packing displays a wave-like arrangement of molecules parallel to b, in which anion layers are linked by medium–weak hydrogen bonds to the ammonium cation, giving rise to a three-dimensional network. The average N...O and N...N distances are 2.843 (2) and 3.025 (3) Å, respectively.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.067
• wR factor = 0.142
• Data-to-parameter ratio = 16.6

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT230_ALERT_2_B Hirshfeld Test Diff for    N1     -   C1      ..      16.02 su
PLAT353_ALERT_3_B Long    N-H Bond (0.87A)   N4     -   H4A    ...       1.10 Ang.

Alert level C
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT230_ALERT_2_C Hirshfeld Test Diff for    N2     -   C5      ..       5.78 su
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C1     -   C2      ..       5.97 su
PLAT353_ALERT_3_C Long    N-H Bond (0.87A)   N4     -   H4B    ...       1.02 Ang.
PLAT353_ALERT_3_C Long    N-H Bond (0.87A)   N4     -   H4C    ...       1.01 Ang.
PLAT353_ALERT_3_C Long    N-H Bond (0.87A)   N4     -   H4D    ...       1.03 Ang.

   0 ALERT level A = In general: serious problem
   2 ALERT level B = Potentially serious problem
   6 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
   3 ALERT type 2 Indicator that the structure model may be wrong or deficient
   4 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: COLLECT (Hooft, 1999); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: SCALEPACK and DENZO (Otwinowski & Minor, 1997); 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); software used to prepare material for publication: PLATON (Spek, 2003).

Ammonium dicyano(cyanoacetyl)methanide

Crystal data

H4N^+·C6H2N3O^−	F(000) = 312
Mr = 150.15	Dx = 1.334 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3286 reflections
a = 8.3642 (6) Å	θ = 1.0–27.5°
b = 12.0104 (9) Å	µ = 0.10 mm^−1
c = 7.6033 (4) Å	T = 298 K
β = 101.790 (4)°	Prism, yellow
V = 747.69 (9) Å^3	0.30 × 0.08 × 0.08 mm
Z = 4

Data collection

Nonius KappaCCD diffractometer	1164 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.083
Horizonally mounted graphite crystal monochromator	θmax = 27.6°, θmin = 2.5°
Detector resolution: 9 pixels mm^-1	h = −9→9
CCD scans	k = −15→15
8956 measured reflections	l = −10→9
1707 independent reflections

Refinement

Refinement on F^2	w = 1/[σ^2(Fo^2) + (0.091P)^2] where P = (Fo^2 + 2Fc^2)/3
Least-squares matrix: full	(Δ/σ)max < 0.001
R[F^2 > 2σ(F^2)] = 0.067	Δρmax = 0.31 e Å^−3
wR(F^2) = 0.142	Δρmin = −0.17 e Å^−3
S = 0.94	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
1707 reflections	Extinction coefficient: 0.063 (16)
103 parameters	Absolute structure: no
H-atom parameters constrained

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
O1	0.37957 (16)	0.20723 (12)	0.33691 (19)	0.0554 (5)
N1	0.4135 (3)	−0.06805 (18)	0.2687 (3)	0.0786 (7)
N2	0.1880 (3)	0.46308 (18)	0.3648 (3)	0.0766 (7)
N3	−0.1492 (2)	0.20036 (16)	0.4635 (3)	0.0633 (6)
C1	0.3227 (3)	−0.01431 (19)	0.3235 (3)	0.0556 (6)
C2	0.2087 (3)	0.05612 (18)	0.3911 (3)	0.0576 (6)
H2A	0.2137	0.0393	0.5169	0.092 (6)*
H2B	0.0987	0.0404	0.3260	0.092 (6)*
C3	0.2457 (2)	0.17901 (16)	0.3716 (2)	0.0429 (5)
C4	0.1270 (2)	0.25615 (17)	0.3975 (2)	0.0441 (5)
C5	0.1592 (2)	0.3706 (2)	0.3808 (3)	0.0523 (6)
C6	−0.0245 (2)	0.22544 (17)	0.4348 (3)	0.0459 (5)
N4	0.59598 (17)	0.16625 (12)	0.10490 (18)	0.0380 (4)
H4A	0.6718	0.0911	0.1247	0.141 (6)*
H4B	0.5136	0.1695	−0.0139	0.141 (6)*
H4C	0.5161	0.1648	0.1882	0.141 (6)*
H4D	0.6760	0.2323	0.1136	0.141 (6)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0452 (8)	0.0604 (10)	0.0661 (9)	−0.0045 (7)	0.0239 (7)	−0.0073 (6)
N1	0.0908 (16)	0.0704 (16)	0.0807 (15)	−0.0117 (11)	0.0319 (13)	0.0139 (11)
N2	0.0787 (15)	0.0550 (14)	0.0983 (16)	0.0024 (11)	0.0237 (12)	−0.0105 (11)
N3	0.0502 (11)	0.0656 (13)	0.0793 (14)	0.0008 (10)	0.0252 (10)	−0.0011 (9)
C1	0.0598 (13)	0.0503 (13)	0.0583 (12)	−0.0036 (11)	0.0161 (10)	0.0015 (11)
C2	0.0538 (13)	0.0502 (14)	0.0749 (16)	−0.0006 (10)	0.0275 (11)	−0.0001 (10)
C3	0.0410 (10)	0.0498 (12)	0.0399 (10)	−0.0025 (8)	0.0131 (8)	−0.0036 (8)
C4	0.0412 (11)	0.0454 (12)	0.0470 (11)	−0.0005 (8)	0.0120 (8)	−0.0032 (9)
C5	0.0521 (12)	0.0485 (14)	0.0574 (12)	−0.0017 (10)	0.0135 (9)	−0.0040 (10)
C6	0.0417 (11)	0.0489 (13)	0.0482 (11)	−0.0003 (9)	0.0119 (9)	0.0014 (9)
N4	0.0333 (8)	0.0418 (9)	0.0417 (8)	0.0004 (6)	0.0143 (6)	0.0032 (6)

Geometric parameters (Å, º)

O1—C3	1.249 (2)	C1—C2	1.445 (3)
N1—C1	1.139 (3)	C2—C3	1.522 (3)
N2—C5	1.148 (3)	C3—C4	1.401 (3)
N3—C6	1.149 (3)	C4—C6	1.403 (3)
N4—H4A	1.0961	C4—C5	1.411 (3)
N4—H4B	1.0184	C2—H2A	0.9703
N4—H4C	1.0103	C2—H2B	0.9699
N4—H4D	1.0313
O1···N4	2.817 (2)	C1···H4D^ix	3.0805
O1···N4^i	2.869 (2)	C1···H4C	2.9970
O1···H4C	1.8358	C3···H4B^i	2.8801
O1···H4B^i	2.0537	C3···H4C	2.8945
N1···N4^ii	3.062 (3)	C5···H4A^iii	3.0060
N2···N4^iii	3.017 (3)	C5···H4B^i	2.9481
N3···C1^iv	3.268 (3)	C5···H2A^vii	3.0910
N3···N4^v	3.126 (3)	C6···H2B	2.6524
N3···N4^vi	3.033 (2)	C6···H2A	2.9750
N3···C2^iv	3.344 (3)	H2A···N3^iv	2.9376
N4···N1^ii	3.062 (3)	H2A···C6	2.9750
N4···O1^vii	2.869 (2)	H2A···N2^i	2.6973
N4···N3^viii	3.033 (2)	H2A···C5^i	3.0910
N4···N2^ix	3.017 (3)	H2B···N2^xiii	2.7012
N4···N3^x	3.126 (3)	H2B···C6	2.6524
N4···O1	2.817 (2)	H4A···N2^ix	1.9251
N1···H4A^ii	2.9432	H4A···C5^ix	3.0060
N1···H4D^ix	2.7177	H4A···N1^ii	2.9432
N1···H4B^ii	2.4683	H4B···N1^ii	2.4683
N2···H4A^iii	1.9251	H4B···O1^vii	2.0537
N2···H2A^vii	2.6974	H4B···C3^vii	2.8801
N2···H2B^xi	2.7012	H4B···C5^vii	2.9481
N3···H2A^iv	2.9376	H4C···O1	1.8358
N3···H4D^v	2.7876	H4C···C1	2.9970
N3···H4D^vi	2.1855	H4C···C3	2.8945
C1···C1^xii	3.587 (3)	H4D···N3^x	2.7876
C1···N3^iv	3.268 (3)	H4D···N1^iii	2.7177
C2···N3^iv	3.344 (3)	H4D···C1^iii	3.0805
C4···C6^vii	3.495 (3)	H4D···N3^viii	2.1855
C6···C4^i	3.495 (3)
H4A—N4—H4B	114.90	C5—C4—C6	118.10 (17)
H4A—N4—H4C	109.73	C3—C4—C6	123.36 (18)
H4A—N4—H4D	105.93	C3—C4—C5	118.52 (16)
H4B—N4—H4C	98.21	N2—C5—C4	178.4 (2)
H4B—N4—H4D	109.90	N3—C6—C4	179.3 (2)
H4C—N4—H4D	118.47	H2A—C2—H2B	107.91
N1—C1—C2	178.7 (3)	C1—C2—H2A	109.26
C1—C2—C3	111.78 (19)	C1—C2—H2B	109.29
O1—C3—C2	119.54 (18)	C3—C2—H2A	109.25
C2—C3—C4	117.62 (17)	C3—C2—H2B	109.27
O1—C3—C4	122.83 (18)
C1—C2—C3—O1	−13.9 (3)	O1—C3—C4—C6	179.32 (19)
C1—C2—C3—C4	167.42 (18)	C2—C3—C4—C5	179.73 (19)
O1—C3—C4—C5	1.1 (3)	C2—C3—C4—C6	−2.0 (3)

Symmetry codes: (i) x, −y+1/2, z+1/2; (ii) −x+1, −y, −z; (iii) −x+1, y+1/2, −z+1/2; (iv) −x, −y, −z+1; (v) x−1, y, z; (vi) x−1, −y+1/2, z+1/2; (vii) x, −y+1/2, z−1/2; (viii) x+1, −y+1/2, z−1/2; (ix) −x+1, y−1/2, −z+1/2; (x) x+1, y, z; (xi) −x, y+1/2, −z+1/2; (xii) −x+1, −y, −z+1; (xiii) −x, y−1/2, −z+1/2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N4—H4A···N2^ix	1.10	1.93	3.017 (3)	174
N4—H4B···O1^vii	1.02	2.05	2.869 (2)	135
N4—H4C···O1	1.01	1.84	2.817 (2)	163
N4—H4D···N3^viii	1.03	2.19	3.033 (2)	138

Symmetry codes: (vii) x, −y+1/2, z−1/2; (viii) x+1, −y+1/2, z−1/2; (ix) −x+1, y−1/2, −z+1/2.