Crystal structure, thermodynamic properties and detonation characterization of bis­(5-amino-1,2,4-triazol-3-yl)methane

Bis(5-amino-1,2,4-triazol-3-yl)methane (BATZM, C₅H₈N₈) was synthesized and its crystal structure characterized by single-crystal X-ray diffraction; it belongs to the space group Fdd2 (ortho­rhom­bic) with Z = 8. The structure of BATZM can be described as a V-shaped mol­ecule with reasonable chemical geometry and no disorder. The specific molar heat capacity (C_p,m) of BATZM was determined using the continuous C_p mode of a microcalorimeter and theoretical calculations, and the C_p,m value is 211.19 J K⁻¹ mol⁻¹ at 298.15 K. The relative deviations between the theoretical and experimental values of C_p,m, H_T – H_298.15K and S_T – S_298.15K of BATZM are almost equivalent at each temperature. The detonation velocity (D) and detonation pressure (P) of BATZM were estimated using the nitro­gen equivalent equation according to the experimental density; BATZM has a higher detonation velocity (7954.87 ± 3.29 m s⁻¹) and detonation pressure (25.72 ± 0.03 GPa) than TNT.

Computing details

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2018 (Sheldrick, 2015); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Bis(5-amino-1,2,4-triazol-3-yl)methane

Crystal data

C5H8N8	Dx = 1.496 Mg m^−3
Mr = 180.19	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Fdd2	Cell parameters from 918 reflections
a = 18.632 (3) Å	θ = 3.0–25.9°
b = 19.933 (3) Å	µ = 0.11 mm^−1
c = 4.3095 (6) Å	T = 296 K
V = 1600.6 (4) Å^3	Acicular, colourless
Z = 8	0.38 × 0.28 × 0.14 mm
F(000) = 752

Data collection

Bruker APEXII CCD diffractometer	757 reflections with I > 2σ(I)
φ and ω scans	Rint = 0.016
Absorption correction: multi-scan (SADABS; Bruker, 2009)	θmax = 28.0°, θmin = 3.0°
Tmin = 0.960, Tmax = 0.985	h = −24→23
1858 measured reflections	k = −9→24
816 independent reflections	l = −5→4

Refinement

Refinement on F^2	Hydrogen site location: mixed
Least-squares matrix: full	H atoms treated by a mixture of independent and constrained refinement
R[F^2 > 2σ(F^2)] = 0.028	w = 1/[σ^2(Fo^2) + (0.0322P)^2 + 0.6778P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.068	(Δ/σ)max < 0.001
S = 1.07	Δρmax = 0.12 e Å^−3
816 reflections	Δρmin = −0.13 e Å^−3
73 parameters	Extinction correction: SHELXL2018 (Sheldrick, 2015), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
5 restraints	Extinction coefficient: 0.0044 (7)
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack x determined using 253 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013)
Secondary atom site location: difference Fourier map	Absolute structure parameter: 1.0 (10)

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
N2	0.08768 (7)	0.07813 (8)	−0.1174 (4)	0.0339 (4)
C3	0.000000	0.000000	−0.3477 (7)	0.0320 (6)
C1	0.01192 (9)	0.14092 (9)	0.1546 (4)	0.0266 (4)
N3	−0.02808 (7)	0.09508 (7)	0.0117 (4)	0.0268 (4)
C2	0.02091 (9)	0.05860 (8)	−0.1521 (4)	0.0261 (4)
N1	0.08068 (7)	0.13222 (8)	0.0808 (4)	0.0341 (4)
N4	−0.01377 (9)	0.19194 (8)	0.3320 (4)	0.0358 (5)
H3	0.0419 (9)	−0.0126 (10)	−0.478 (5)	0.043*
H4A	−0.0565 (7)	0.1859 (10)	0.403 (6)	0.043*
H4B	0.0172 (9)	0.2130 (10)	0.448 (5)	0.043*
H1	0.1188 (8)	0.1486 (9)	0.160 (5)	0.043*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N2	0.0245 (7)	0.0391 (8)	0.0380 (10)	−0.0006 (6)	0.0033 (8)	−0.0040 (8)
C3	0.0329 (13)	0.0359 (14)	0.0271 (16)	−0.0005 (11)	0.000	0.000
C1	0.0222 (8)	0.0302 (9)	0.0272 (11)	−0.0002 (7)	−0.0004 (8)	0.0060 (8)
N3	0.0203 (7)	0.0297 (8)	0.0303 (9)	−0.0003 (6)	−0.0006 (7)	0.0022 (6)
C2	0.0233 (8)	0.0304 (9)	0.0246 (10)	0.0004 (7)	0.0011 (8)	0.0056 (8)
N1	0.0199 (7)	0.0411 (9)	0.0412 (10)	−0.0047 (7)	−0.0016 (7)	−0.0058 (8)
N4	0.0311 (8)	0.0363 (9)	0.0398 (12)	−0.0032 (7)	0.0040 (9)	−0.0069 (8)

Geometric parameters (Å, º)

N2—C2	1.312 (2)	C1—N1	1.332 (2)
N2—N1	1.382 (2)	C1—N4	1.359 (2)
C3—C2	1.492 (2)	N3—C2	1.364 (2)
C3—C2^i	1.492 (2)	N1—H1	0.853 (12)
C3—H3	0.993 (16)	N4—H4A	0.861 (12)
C3—H3^i	0.993 (16)	N4—H4B	0.871 (12)
C1—N3	1.330 (2)
C2—N2—N1	102.28 (14)	C1—N3—C2	103.35 (14)
C2—C3—C2^i	111.2 (2)	N2—C2—N3	114.66 (16)
C2—C3—H3	108.1 (12)	N2—C2—C3	122.98 (14)
C2^i—C3—H3	109.1 (12)	N3—C2—C3	122.34 (14)
C2—C3—H3^i	109.1 (12)	C1—N1—N2	109.88 (15)
C2^i—C3—H3^i	108.1 (12)	C1—N1—H1	130.9 (15)
H3—C3—H3^i	111 (3)	N2—N1—H1	117.9 (14)
N3—C1—N1	109.83 (16)	C1—N4—H4A	114.9 (15)
N3—C1—N4	125.24 (15)	C1—N4—H4B	116.7 (14)
N1—C1—N4	124.79 (16)	H4A—N4—H4B	118 (2)
N1—C1—N3—C2	−0.1 (2)	C2^i—C3—C2—N2	106.21 (19)
N4—C1—N3—C2	175.64 (18)	C2^i—C3—C2—N3	−72.01 (15)
N1—N2—C2—N3	−1.0 (2)	N3—C1—N1—N2	−0.5 (2)
N1—N2—C2—C3	−179.38 (17)	N4—C1—N1—N2	−176.29 (17)
C1—N3—C2—N2	0.8 (2)	C2—N2—N1—C1	0.92 (19)
C1—N3—C2—C3	179.12 (18)

Symmetry code: (i) −x, −y, z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···N3^ii	0.85 (1)	1.98 (1)	2.782 (2)	157 (2)
N4—H4B···N4^iii	0.87 (1)	2.52 (2)	3.204 (2)	136 (2)
N4—H4A···N2^iv	0.86 (1)	2.22 (1)	3.082 (2)	174 (2)

Symmetry codes: (ii) x+1/4, −y+1/4, z+1/4; (iii) −x, −y+1/2, z+1/2; (iv) x−1/4, −y+1/4, z+3/4.