The synthesis, crystal structure and thermal properties of an energetic compound: the hydrated azanium salt of 3,6-bis­[(1H-1,2,3,4-tetra­zol-5-yl)amino]-1,2,4,5-tetra­zine

The energetic ionic salt bis­(1-amino­guanidin-2-ium) 5,5′-[1,2,4,5-tetra­zine-3,6-diylbis(aza­nedi­yl)]bis­(1H-1,2,3,4-tetra­zol-1-ide) dihydrate, 2CH₇N₄⁺·C₄H₂N₁₄²⁻·2H₂O, (I), with a high nitro­gen content, has been synthesized and examined by elemental analysis, Fourier transform IR spectrometry, ¹H NMR spectroscopy and single-crystal X-ray crystallography. Compound (I) crystallizes in the monoclinic space group P2₁/c with two water mol­ecules. However, the water mol­ecules are disordered about an inversion centre and were modelled as half-occupancy mol­ecules in the structure. The crystal structure reveals a three-dimensional network of mol­ecules linked through N—H...N, N—H...O, O—H...N and O—H...O hydrogen bonds. Thermal decomposition was investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The exothermic peak temperature is 509.72 K, which indicates that hydrated salt (I) exhibits good thermal stability. Non-isothermal reaction kinetic parameters were calculated via both the Kissinger and the Ozawa methods to yield activation energies of E_k = 239.07 kJ mol⁻¹, lgA_k = 22.79 s⁻¹ and E_O = 235.38 kJ mol⁻¹ for (I). Additionally, the thermal safety was evaluated by calculating critical temperatures and thermodynamic values, viz. T_SADT, T_TIT, T_b, ΔS^≠, ΔH^≠ and ΔG^≠. The results reveal that (I) exhibits good thermal safety compared to other ion salts of 3,6-bis­[(1H-1,2,3,4-tetra­zol-5-yl)amino]-1,2,4,5-tetra­zine (BTATz).

Computing details

Program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

Bis[amino(hydrazinyl)methylidene]azanium 5,5'-[1,2,4,5-tetrazine-3,6-diylbis(azanediyl)]bis(1H-1,2,3,4-tetrazol-1-ide) dihydrate

Crystal data

2CH7N4^+·C4H2N14^2^−·2H2O	F(000) = 452
Mr = 432.44	Dx = 1.670 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 12.231 (6) Å	Cell parameters from 618 reflections
b = 3.919 (2) Å	θ = 2.9–21.9°
c = 17.968 (9) Å	µ = 0.13 mm^−1
β = 92.949 (9)°	T = 296 K
V = 860.1 (8) Å^3	Block, red
Z = 2	0.37 × 0.22 × 0.11 mm

Data collection

Bruker APEXII CCD diffractometer	1028 reflections with I > 2σ(I)
φ and ω scans	Rint = 0.064
Absorption correction: multi-scan (SADABS; Bruker, 2005)	θmax = 25.4°, θmin = 2.3°
Tmin = 0.617, Tmax = 0.745	h = −14→11
4049 measured reflections	k = −4→4
1572 independent reflections	l = −21→21

Refinement

Refinement on F^2	Hydrogen site location: difference Fourier map
Least-squares matrix: full	H atoms treated by a mixture of independent and constrained refinement
R[F^2 > 2σ(F^2)] = 0.057	w = 1/[σ^2(Fo^2) + (0.0994P)^2] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.182	(Δ/σ)max < 0.001
S = 1.06	Δρmax = 0.31 e Å^−3
1572 reflections	Δρmin = −0.36 e Å^−3
171 parameters	Extinction correction: SHELXL2014 (Sheldrick, 2015), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
12 restraints	Extinction coefficient: 0.042 (9)

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq	Occ. (<1)
N1	0.7274 (2)	0.2551 (9)	0.35909 (15)	0.0469 (8)
N2	0.7851 (2)	0.4089 (9)	0.30677 (15)	0.0525 (9)
N3	0.7236 (2)	0.4566 (8)	0.24691 (15)	0.0479 (8)
N4	0.6225 (2)	0.3367 (8)	0.25700 (14)	0.0438 (8)
N5	0.5399 (2)	0.0592 (8)	0.35698 (14)	0.0412 (8)
H5	0.494 (3)	−0.039 (10)	0.329 (2)	0.049*
N6	0.5876 (2)	0.1925 (7)	0.48181 (13)	0.0370 (7)
N7	0.5644 (2)	0.1620 (7)	0.55235 (13)	0.0366 (7)
N8	0.2560 (3)	0.3882 (9)	0.38392 (18)	0.0484 (9)
H8A	0.269 (3)	0.284 (10)	0.340 (2)	0.058*
H8B	0.309 (3)	0.539 (11)	0.396 (2)	0.058*
N9	0.1003 (3)	0.0876 (9)	0.40739 (18)	0.0506 (9)
H9A	0.089 (3)	0.028 (12)	0.366 (2)	0.061*
H9B	0.048 (3)	0.034 (11)	0.442 (2)	0.061*
N10	0.1906 (2)	0.3792 (8)	0.50133 (15)	0.0437 (8)
H10	0.237 (3)	0.503 (11)	0.519 (2)	0.052*
N11	0.1146 (3)	0.2539 (10)	0.55001 (17)	0.0475 (9)
H11A	0.151 (3)	0.104 (11)	0.580 (2)	0.057*
H11B	0.094 (3)	0.414 (12)	0.572 (2)	0.057*
C1	0.6288 (3)	0.2167 (8)	0.32612 (16)	0.0334 (8)
C2	0.5225 (2)	0.0304 (8)	0.43043 (16)	0.0321 (8)
C3	0.1833 (3)	0.2839 (9)	0.43030 (18)	0.0388 (8)
O1	0.9873 (7)	0.731 (5)	0.2850 (5)	0.120 (5)	0.55 (2)
H1A	0.9692	0.5451	0.2650	0.180*	0.55 (2)
H1B	0.9328	0.8245	0.3043	0.180*	0.55 (2)
O1A	1.0062 (15)	0.990 (10)	0.2515 (16)	0.199 (9)	0.45 (2)
H1AA	1.0644	0.8801	0.2441	0.298*	0.45 (2)
H1AB	0.9586	0.8563	0.2316	0.298*	0.45 (2)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.0468 (16)	0.066 (2)	0.0277 (14)	−0.0106 (15)	−0.0019 (12)	0.0068 (14)
N2	0.0576 (18)	0.071 (2)	0.0294 (15)	−0.0139 (17)	0.0019 (14)	0.0014 (15)
N3	0.0583 (19)	0.057 (2)	0.0283 (15)	−0.0043 (16)	0.0031 (13)	0.0058 (14)
N4	0.0492 (17)	0.058 (2)	0.0235 (14)	0.0035 (14)	−0.0006 (12)	0.0050 (13)
N5	0.0461 (17)	0.058 (2)	0.0194 (13)	−0.0133 (14)	−0.0038 (12)	−0.0027 (13)
N6	0.0421 (15)	0.0468 (18)	0.0217 (13)	−0.0022 (13)	−0.0008 (11)	−0.0016 (12)
N7	0.0429 (15)	0.0461 (19)	0.0207 (13)	−0.0036 (13)	−0.0003 (11)	−0.0021 (11)
N8	0.0533 (18)	0.056 (2)	0.0357 (17)	−0.0074 (16)	0.0043 (14)	−0.0084 (15)
N9	0.0551 (19)	0.060 (2)	0.0357 (17)	−0.0124 (16)	−0.0067 (15)	−0.0096 (16)
N10	0.0461 (17)	0.053 (2)	0.0312 (15)	−0.0108 (14)	−0.0022 (13)	−0.0048 (14)
N11	0.0535 (19)	0.053 (2)	0.0356 (18)	−0.0047 (16)	0.0017 (14)	−0.0006 (15)
C1	0.0431 (18)	0.0356 (19)	0.0214 (15)	0.0042 (14)	−0.0006 (13)	−0.0009 (13)
C2	0.0354 (16)	0.037 (2)	0.0234 (15)	0.0030 (14)	−0.0036 (12)	−0.0008 (13)
C3	0.0447 (19)	0.037 (2)	0.0338 (18)	0.0068 (16)	−0.0047 (15)	0.0007 (15)
O1	0.111 (6)	0.132 (9)	0.115 (7)	0.011 (5)	−0.013 (4)	−0.014 (6)
O1A	0.203 (11)	0.196 (13)	0.196 (12)	−0.005 (9)	−0.002 (8)	−0.015 (9)

Geometric parameters (Å, º)

N1—N2	1.347 (4)	N9—H9A	0.79 (4)
N1—C1	1.324 (4)	N9—H9B	0.93 (4)
N2—N3	1.294 (4)	N9—C3	1.322 (5)
N3—N4	1.344 (4)	N10—H10	0.80 (4)
N4—C1	1.326 (4)	N10—N11	1.399 (4)
N5—H5	0.83 (4)	N10—C3	1.328 (4)
N5—C1	1.390 (4)	N11—H11A	0.90 (4)
N5—C2	1.352 (4)	N11—H11B	0.79 (4)
N6—N7	1.318 (3)	C2—N7^i	1.352 (4)
N6—C2	1.347 (4)	O1—H1A	0.8352
N7—C2^i	1.352 (4)	O1—H1B	0.8500
N8—H8A	0.90 (4)	O1A—H1AA	0.8493
N8—H8B	0.90 (4)	O1A—H1AB	0.8500
N8—C3	1.315 (5)
C1—N1—N2	103.6 (3)	C3—N10—H10	125 (3)
N3—N2—N1	110.0 (3)	C3—N10—N11	119.2 (3)
N2—N3—N4	109.7 (3)	N10—N11—H11A	106 (2)
C1—N4—N3	103.9 (3)	N10—N11—H11B	106 (3)
C1—N5—H5	119 (2)	H11A—N11—H11B	112 (4)
C2—N5—H5	115 (2)	N1—C1—N4	112.8 (3)
C2—N5—C1	126.3 (3)	N1—C1—N5	125.8 (3)
N7—N6—C2	117.9 (3)	N4—C1—N5	121.4 (3)
N6—N7—C2^i	118.8 (2)	N6—C2—N5	120.8 (3)
H8A—N8—H8B	111 (4)	N6—C2—N7^i	123.4 (3)
C3—N8—H8A	124 (2)	N7^i—C2—N5	115.8 (3)
C3—N8—H8B	123 (3)	N8—C3—N9	121.1 (3)
H9A—N9—H9B	118 (4)	N8—C3—N10	120.5 (3)
C3—N9—H9A	124 (3)	N9—C3—N10	118.4 (3)
C3—N9—H9B	118 (3)	H1A—O1—H1B	110.9
N11—N10—H10	116 (3)	H1AA—O1A—H1AB	100.4
N1—N2—N3—N4	0.1 (4)	N11—N10—C3—N8	−177.6 (3)
N2—N1—C1—N4	0.1 (4)	N11—N10—C3—N9	3.6 (5)
N2—N1—C1—N5	177.9 (3)	C1—N1—N2—N3	−0.1 (4)
N2—N3—N4—C1	0.0 (4)	C1—N5—C2—N6	7.5 (5)
N3—N4—C1—N1	0.0 (4)	C1—N5—C2—N7^i	−173.9 (3)
N3—N4—C1—N5	−178.0 (3)	C2—N5—C1—N1	26.0 (6)
N7—N6—C2—N5	178.1 (3)	C2—N5—C1—N4	−156.4 (3)
N7—N6—C2—N7^i	−0.4 (5)	C2—N6—N7—C2^i	0.4 (5)

Symmetry code: (i) −x+1, −y, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N5—H5···N4^ii	0.83 (4)	2.10 (4)	2.912 (4)	165 (4)
N8—H8A···N3^ii	0.90 (4)	2.03 (4)	2.917 (5)	166 (4)
N8—H8B···N6^iii	0.90 (4)	2.69 (4)	3.421 (4)	140 (3)
N8—H8B···N7^iii	0.90 (4)	2.12 (4)	2.997 (5)	168 (4)
N9—H9A···O1^iv	0.79 (4)	2.20 (5)	2.897 (13)	148 (4)
N9—H9A···O1A^iv	0.79 (4)	2.24 (5)	3.00 (2)	159 (4)
N9—H9B···N11^v	0.93 (4)	2.30 (4)	3.080 (5)	141 (3)
N10—H10···N1^iii	0.80 (4)	2.40 (4)	3.015 (4)	135 (3)
N10—H10···N6^iii	0.80 (4)	2.46 (4)	3.191 (4)	153 (4)
N11—H11A···N1^i	0.90 (4)	2.28 (4)	3.171 (5)	168 (3)
N11—H11B···N2^iii	0.79 (4)	2.66 (4)	3.091 (4)	116 (3)
O1—H1A···O1^vi	0.84	1.63	2.357 (11)	144
O1A—H1AA···N2^vii	0.85	2.10	2.83 (2)	143
O1A—H1AA···N3^vii	0.85	2.61	3.305 (19)	140

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