C9H17N2+·C7H3N2O7−	F(000) = 800
Mr = 380.35	Dx = 1.489 Mg m−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yabc	Cell parameters from 1891 reflections
a = 6.1537 (3) Å	θ = 3.5–26.6°
b = 19.1541 (14) Å	µ = 0.12 mm−1
c = 14.5527 (11) Å	T = 200 K
β = 98.343 (6)°	Needle, yellow
V = 1697.2 (2) Å3	0.30 × 0.13 × 0.10 mm
Z = 4