Table 2. Experimental details.

Crystal data
Chemical formula	NH4 +·C3H2N3O2 −
M r	130.12
Crystal system, space group	Orthorhombic, P n a21
Temperature (K)	173
a, b, c (Å)	10.7174 (5), 13.8944 (7), 4.0643 (2)
V (Å3)	605.22 (5)
Z	4
Radiation type	Mo Kα
μ (mm−1)	0.12
Crystal size (mm)	0.37 × 0.30 × 0.21
Data collection
Diffractometer	Bruker APEXII CCD
No. of measured, independent and observed [I > 2σ(I)] reflections	7798, 1420, 1304
R int	0.031
(sin θ/λ)max (Å−1)	0.663
Refinement
R[F 2 > 2σ(F 2)], wR(F 2), S	0.032, 0.081, 1.10
No. of reflections	1420
No. of parameters	106
No. of restraints	22
H-atom treatment	All H-atom parameters refined
Δρmax, Δρmin (e Å−3)	0.19, −0.14

Computer programs: SMART-NT (Bruker, 1998 ▸), SAINT-NT (Bruker, 1999 ▸), SHELXS97 (Sheldrick, 2008 ▸), SHELXL2014/7 (Sheldrick, 2015 ▸), DIAMOND (Brandenburg, 1999 ▸) and WinGX (Farrugia, 2012 ▸).