Bis-(3,5-diamino-4H-1,2,4-triazol-1-ium) 3,4-dioxocyclo-butane-1,2-diolate.

The asymmetric unit of the title compound, 2C2H6N5(+)·C4O4(2-), contains two 3,5-diamino-4H-1,2,4-triazolium cations and one squarate dianion. The squaric acid mol-ecule donated one H atom to each of the two 3,5-diamino-1,2,4-triazole mol-ecules at their N atoms. The squaric acid dianion has four C-O bonds which are shorter than a normal single C-O bond (1.426 Å) and are slightly longer than a normal C=O bond (1.23 Å), which indicates the degree of electron delocalization in the dianion. In the crystal, the cations and dianions are linked by N-H⋯N and N-H⋯O hydrogen bonds into a three-dimensional network.

Related literature

For background to the acid–base chemistry of squarate acid, see: Mathew et al. (2002 ▶); Frankenbach et al. (1992 ▶); Yeşilel et al. (2008 ▶); Bertolasi et al. (2001 ▶); Correa et al. (2007 ▶). For a related structure, see: Uçar et al. (2004 ▶). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986 ▶).

Experimental

Crystal data

2C2H6N5 +·C4O4 2−

M = 312.28

Monoclinic,

a = 15.7186 (2) Å

b = 11.6533 (2) Å

c = 6.8618 (1) Å

β = 91.734 (1)°

V = 1256.32 (3) Å3

Z = 4

Mo Kα radiation

μ = 0.14 mm−1

T = 100 K

0.44 × 0.20 × 0.14 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2009 ▶) T min = 0.943, T max = 0.982

19113 measured reflections

4965 independent reflections

3911 reflections with I > 2σ(I)

R int = 0.028

Refinement

R[F 2 > 2σ(F 2)] = 0.040

wR(F 2) = 0.108

S = 1.03

4965 reflections

247 parameters

All H-atom parameters refined

Δρmax = 0.43 e Å−3

Δρmin = −0.32 e Å−3

Data collection: APEX2 (Bruker, 2009 ▶); cell refinement: SAINT (Bruker, 2009 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ▶).

Click here for additional data file.

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S160053681300322X/rz5040sup1.cif

Click here for additional data file.

Structure factors: contains datablock(s) I. DOI: 10.1107/S160053681300322X/rz5040Isup2.hkl

Click here for additional data file.

Supplementary material file. DOI: 10.1107/S160053681300322X/rz5040Isup3.cml

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

2C2H6N5+·C4O42−	F(000) = 648
Mr = 312.28	Dx = 1.651 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 7050 reflections
a = 15.7186 (2) Å	θ = 2.2–33.7°
b = 11.6533 (2) Å	µ = 0.14 mm−1
c = 6.8618 (1) Å	T = 100 K
β = 91.734 (1)°	Block, colourless
V = 1256.32 (3) Å3	0.44 × 0.20 × 0.14 mm
Z = 4

Bruker SMART APEXII CCD area-detector diffractometer	4965 independent reflections
Radiation source: fine-focus sealed tube	3911 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.028
φ and ω scans	θmax = 33.7°, θmin = 1.3°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −24→23
Tmin = 0.943, Tmax = 0.982	k = −18→12
19113 measured reflections	l = −10→10

Refinement on F2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.108	All H-atom parameters refined
S = 1.03	w = 1/[σ2(Fo2) + (0.0597P)2 + 0.1328P] where P = (Fo2 + 2Fc2)/3
4965 reflections	(Δ/σ)max = 0.001
247 parameters	Δρmax = 0.43 e Å−3
0 restraints	Δρmin = −0.32 e Å−3

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

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.

	x	y	z	Uiso*/Ueq
O1	0.21331 (4)	1.07699 (5)	0.54430 (10)	0.01452 (13)
O2	0.37416 (4)	0.94620 (5)	0.36357 (10)	0.01592 (14)
O3	0.29531 (4)	0.70043 (5)	0.48973 (11)	0.01665 (14)
O4	0.13065 (4)	0.82957 (5)	0.65486 (10)	0.01628 (14)
C1	0.23528 (5)	0.97349 (7)	0.52898 (13)	0.01176 (15)
C2	0.30810 (5)	0.91452 (7)	0.44836 (13)	0.01202 (15)
C3	0.27269 (5)	0.80280 (7)	0.50302 (13)	0.01267 (16)
C4	0.19890 (5)	0.86217 (7)	0.57988 (13)	0.01233 (16)
N1A	−0.07849 (5)	0.38750 (6)	0.31736 (11)	0.01324 (15)
N2A	−0.06499 (5)	0.57809 (6)	0.31893 (11)	0.01364 (15)
N3A	0.00592 (5)	0.52443 (6)	0.23974 (12)	0.01388 (15)
N4A	−0.19073 (5)	0.49920 (7)	0.44806 (13)	0.01773 (17)
N5A	0.05462 (5)	0.33657 (7)	0.17618 (13)	0.01821 (17)
C5A	−0.11444 (5)	0.49176 (7)	0.36330 (13)	0.01248 (16)
C6A	−0.00190 (5)	0.41097 (7)	0.24079 (13)	0.01293 (16)
N1B	0.58254 (5)	0.65997 (6)	0.21916 (11)	0.01269 (14)
N2B	0.57382 (5)	0.84985 (6)	0.24748 (12)	0.01463 (15)
N3B	0.49823 (5)	0.79658 (6)	0.29850 (12)	0.01433 (15)
N4B	0.70576 (5)	0.77532 (7)	0.14462 (12)	0.01499 (15)
N5B	0.44176 (5)	0.60870 (7)	0.31739 (13)	0.01730 (16)
C5B	0.62343 (5)	0.76414 (7)	0.20276 (13)	0.01231 (16)
C6B	0.50327 (5)	0.68311 (7)	0.27941 (13)	0.01274 (16)
H1N1	−0.1018 (10)	0.3160 (14)	0.327 (2)	0.040 (4)*
H1N3	0.0528 (9)	0.5685 (13)	0.204 (2)	0.032 (4)*
H1N4	−0.2223 (9)	0.4367 (13)	0.460 (2)	0.037 (4)*
H2N4	−0.2172 (9)	0.5679 (13)	0.456 (2)	0.033 (4)*
H1N5	0.0480 (9)	0.2572 (13)	0.186 (2)	0.037 (4)*
H2N5	0.1053 (10)	0.3664 (13)	0.134 (2)	0.039 (4)*
H2N1	0.6019 (10)	0.5916 (13)	0.193 (2)	0.037 (4)*
H2N3	0.4496 (9)	0.8444 (13)	0.323 (2)	0.037 (4)*
H3N4	0.7334 (8)	0.7088 (12)	0.112 (2)	0.028 (3)*
H4N4	0.7362 (8)	0.8208 (11)	0.2184 (19)	0.028 (3)*
H3N5	0.4482 (9)	0.5311 (13)	0.295 (2)	0.039 (4)*
H4N5	0.3877 (10)	0.6390 (14)	0.371 (2)	0.044 (4)*

	U11	U22	U33	U12	U13	U23
O1	0.0142 (3)	0.0081 (2)	0.0215 (3)	0.0007 (2)	0.0043 (2)	−0.0010 (2)
O2	0.0124 (3)	0.0102 (3)	0.0256 (4)	−0.0002 (2)	0.0086 (2)	0.0010 (2)
O3	0.0149 (3)	0.0082 (3)	0.0272 (4)	0.0016 (2)	0.0067 (2)	0.0004 (2)
O4	0.0124 (3)	0.0103 (3)	0.0267 (4)	−0.0010 (2)	0.0088 (2)	−0.0001 (2)
C1	0.0109 (3)	0.0092 (3)	0.0154 (4)	−0.0008 (3)	0.0023 (3)	−0.0004 (3)
C2	0.0105 (3)	0.0092 (3)	0.0165 (4)	−0.0001 (3)	0.0030 (3)	0.0002 (3)
C3	0.0115 (3)	0.0098 (3)	0.0168 (4)	−0.0001 (3)	0.0032 (3)	0.0005 (3)
C4	0.0115 (3)	0.0091 (3)	0.0166 (4)	−0.0002 (3)	0.0035 (3)	−0.0002 (3)
N1A	0.0128 (3)	0.0090 (3)	0.0182 (4)	−0.0020 (2)	0.0044 (3)	0.0001 (3)
N2A	0.0124 (3)	0.0107 (3)	0.0180 (4)	−0.0002 (2)	0.0043 (3)	−0.0002 (3)
N3A	0.0130 (3)	0.0091 (3)	0.0198 (4)	−0.0011 (2)	0.0053 (3)	0.0010 (3)
N4A	0.0149 (4)	0.0120 (3)	0.0268 (5)	−0.0015 (3)	0.0091 (3)	−0.0011 (3)
N5A	0.0152 (4)	0.0103 (3)	0.0297 (5)	−0.0001 (3)	0.0101 (3)	0.0001 (3)
C5A	0.0131 (4)	0.0102 (3)	0.0143 (4)	−0.0008 (3)	0.0021 (3)	0.0000 (3)
C6A	0.0132 (4)	0.0102 (3)	0.0156 (4)	−0.0014 (3)	0.0034 (3)	0.0009 (3)
N1B	0.0120 (3)	0.0091 (3)	0.0172 (4)	0.0013 (2)	0.0036 (3)	−0.0021 (3)
N2B	0.0129 (3)	0.0115 (3)	0.0198 (4)	0.0000 (3)	0.0055 (3)	−0.0004 (3)
N3B	0.0118 (3)	0.0097 (3)	0.0217 (4)	0.0009 (2)	0.0050 (3)	−0.0017 (3)
N4B	0.0132 (3)	0.0134 (3)	0.0186 (4)	0.0002 (3)	0.0043 (3)	−0.0025 (3)
N5B	0.0131 (3)	0.0121 (3)	0.0271 (4)	−0.0007 (3)	0.0062 (3)	−0.0037 (3)
C5B	0.0139 (4)	0.0105 (3)	0.0127 (4)	0.0004 (3)	0.0027 (3)	−0.0006 (3)
C6B	0.0127 (4)	0.0106 (3)	0.0150 (4)	0.0010 (3)	0.0020 (3)	−0.0012 (3)

O1—C1	1.2599 (10)	N4A—H2N4	0.904 (15)
O2—C2	1.2608 (10)	N5A—C6A	1.3272 (12)
O3—C3	1.2490 (10)	N5A—H1N5	0.934 (15)
O4—C4	1.2622 (10)	N5A—H2N5	0.922 (15)
C1—C2	1.4582 (12)	N1B—C6B	1.3517 (11)
C1—C4	1.4642 (11)	N1B—C5B	1.3798 (11)
C2—C3	1.4690 (12)	N1B—H2N1	0.873 (15)
C3—C4	1.4627 (12)	N2B—C5B	1.3092 (11)
N1A—C6A	1.3559 (11)	N2B—N3B	1.3947 (10)
N1A—C5A	1.3805 (11)	N3B—C6B	1.3313 (11)
N1A—H1N1	0.913 (16)	N3B—H2N3	0.965 (15)
N2A—C5A	1.3127 (11)	N4B—C5B	1.3719 (12)
N2A—N3A	1.4020 (11)	N4B—H3N4	0.919 (14)
N3A—C6A	1.3280 (11)	N4B—H4N4	0.867 (13)
N3A—H1N3	0.937 (15)	N5B—C6B	1.3305 (11)
N4A—C5A	1.3513 (12)	N5B—H3N5	0.922 (15)
N4A—H1N4	0.887 (16)	N5B—H4N5	1.001 (15)
O1—C1—C2	134.67 (8)	N2A—C5A—N4A	126.16 (8)
O1—C1—C4	135.90 (8)	N2A—C5A—N1A	111.86 (8)
C2—C1—C4	89.41 (6)	N4A—C5A—N1A	121.97 (8)
O2—C2—C1	134.74 (8)	N5A—C6A—N3A	125.85 (8)
O2—C2—C3	134.50 (8)	N5A—C6A—N1A	127.51 (8)
C1—C2—C3	90.75 (7)	N3A—C6A—N1A	106.64 (8)
O3—C3—C4	135.13 (8)	C6B—N1B—C5B	106.58 (7)
O3—C3—C2	135.81 (8)	C6B—N1B—H2N1	125.0 (10)
C4—C3—C2	89.06 (6)	C5B—N1B—H2N1	128.4 (10)
O4—C4—C3	134.24 (8)	C5B—N2B—N3B	103.72 (7)
O4—C4—C1	134.98 (8)	C6B—N3B—N2B	111.33 (7)
C3—C4—C1	90.76 (7)	C6B—N3B—H2N3	129.8 (9)
C6A—N1A—C5A	106.58 (7)	N2B—N3B—H2N3	118.2 (9)
C6A—N1A—H1N1	125.0 (10)	C5B—N4B—H3N4	116.6 (8)
C5A—N1A—H1N1	128.3 (10)	C5B—N4B—H4N4	113.4 (8)
C5A—N2A—N3A	103.37 (7)	H3N4—N4B—H4N4	113.5 (11)
C6A—N3A—N2A	111.54 (7)	C6B—N5B—H3N5	121.5 (9)
C6A—N3A—H1N3	128.4 (9)	C6B—N5B—H4N5	118.2 (9)
N2A—N3A—H1N3	119.8 (9)	H3N5—N5B—H4N5	120.3 (13)
C5A—N4A—H1N4	119.5 (10)	N2B—C5B—N4B	124.71 (8)
C5A—N4A—H2N4	119.9 (9)	N2B—C5B—N1B	111.71 (8)
H1N4—N4A—H2N4	117.5 (13)	N4B—C5B—N1B	123.58 (8)
C6A—N5A—H1N5	123.2 (9)	N5B—C6B—N3B	125.61 (8)
C6A—N5A—H2N5	116.8 (10)	N5B—C6B—N1B	127.73 (8)
H1N5—N5A—H2N5	119.6 (13)	N3B—C6B—N1B	106.64 (7)
O1—C1—C2—O2	−1.04 (18)	N3A—N2A—C5A—N4A	178.72 (9)
C4—C1—C2—O2	177.98 (11)	N3A—N2A—C5A—N1A	0.26 (9)
O1—C1—C2—C3	179.83 (10)	C6A—N1A—C5A—N2A	0.32 (10)
C4—C1—C2—C3	−1.15 (7)	C6A—N1A—C5A—N4A	−178.20 (8)
O2—C2—C3—O3	1.85 (19)	N2A—N3A—C6A—N5A	−179.82 (9)
C1—C2—C3—O3	−179.02 (11)	N2A—N3A—C6A—N1A	1.01 (10)
O2—C2—C3—C4	−177.99 (11)	C5A—N1A—C6A—N5A	−179.95 (9)
C1—C2—C3—C4	1.15 (7)	C5A—N1A—C6A—N3A	−0.80 (10)
O3—C3—C4—O4	−2.60 (18)	C5B—N2B—N3B—C6B	−1.43 (10)
C2—C3—C4—O4	177.24 (10)	N3B—N2B—C5B—N4B	−179.41 (8)
O3—C3—C4—C1	179.02 (11)	N3B—N2B—C5B—N1B	1.21 (10)
C2—C3—C4—C1	−1.14 (7)	C6B—N1B—C5B—N2B	−0.61 (10)
O1—C1—C4—O4	1.79 (19)	C6B—N1B—C5B—N4B	180.00 (8)
C2—C1—C4—O4	−177.21 (11)	N2B—N3B—C6B—N5B	179.79 (9)
O1—C1—C4—C3	−179.85 (11)	N2B—N3B—C6B—N1B	1.09 (10)
C2—C1—C4—C3	1.15 (7)	C5B—N1B—C6B—N5B	−178.98 (9)
C5A—N2A—N3A—C6A	−0.80 (9)	C5B—N1B—C6B—N3B	−0.32 (9)

D—H···A	D—H	H···A	D···A	D—H···A
N1A—H1N1···O4i	0.913 (16)	1.761 (16)	2.6677 (9)	171.3 (15)
N3A—H1N3···O4ii	0.937 (15)	1.746 (15)	2.6734 (10)	170.2 (14)
N4A—H1N4···O3i	0.887 (15)	2.003 (15)	2.8877 (10)	175.2 (13)
N4A—H2N4···N4Biii	0.904 (15)	2.565 (15)	3.3917 (12)	152.3 (12)
N5A—H1N5···N2Aiv	0.933 (15)	2.105 (15)	3.0167 (11)	165.3 (13)
N5A—H2N5···O1ii	0.922 (15)	1.940 (15)	2.8621 (11)	177.7 (14)
N1B—H2N1···O2v	0.874 (15)	1.781 (15)	2.6485 (9)	171.8 (15)
N3B—H2N3···O2	0.965 (15)	1.706 (15)	2.6637 (10)	171.2 (14)
N4B—H3N4···O1v	0.920 (14)	2.065 (14)	2.9564 (10)	162.8 (12)
N4B—H4N4···O1vi	0.867 (13)	2.150 (13)	2.9954 (10)	164.9 (12)
N5B—H3N5···N2Bv	0.923 (15)	2.159 (15)	3.0579 (11)	164.3 (12)
N5B—H4N5···O3	1.001 (16)	1.832 (15)	2.8293 (10)	174.2 (12)

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1A—H1N1⋯O4i	0.913 (16)	1.761 (16)	2.6677 (9)	171.3 (15)
N3A—H1N3⋯O4ii	0.937 (15)	1.746 (15)	2.6734 (10)	170.2 (14)
N4A—H1N4⋯O3i	0.887 (15)	2.003 (15)	2.8877 (10)	175.2 (13)
N4A—H2N4⋯N4B iii	0.904 (15)	2.565 (15)	3.3917 (12)	152.3 (12)
N5A—H1N5⋯N2A iv	0.933 (15)	2.105 (15)	3.0167 (11)	165.3 (13)
N5A—H2N5⋯O1ii	0.922 (15)	1.940 (15)	2.8621 (11)	177.7 (14)
N1B—H2N1⋯O2v	0.874 (15)	1.781 (15)	2.6485 (9)	171.8 (15)
N3B—H2N3⋯O2	0.965 (15)	1.706 (15)	2.6637 (10)	171.2 (14)
N4B—H3N4⋯O1v	0.920 (14)	2.065 (14)	2.9564 (10)	162.8 (12)
N4B—H4N4⋯O1vi	0.867 (13)	2.150 (13)	2.9954 (10)	164.9 (12)
N5B—H3N5⋯N2B v	0.923 (15)	2.159 (15)	3.0579 (11)	164.3 (12)
N5B—H4N5⋯O3	1.001 (16)	1.832 (15)	2.8293 (10)	174.2 (12)

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) ; (v) ; (vi) .