[Ni(C6H15NO3)2](C7H5O3)2·4H2O	F(000) = 748
Mr = 703.37	Dx = 1.422 Mg m−3
Monoclinic, P21/n	Cu Kα radiation, λ = 1.54184 Å
a = 8.40515 (12) Å	Cell parameters from 7605 reflections
b = 21.4397 (3) Å	θ = 4.1–75.8°
c = 9.48944 (14) Å	µ = 1.50 mm−1
β = 106.1835 (15)°	T = 293 K
V = 1642.27 (4) Å3	Prism, light-green
Z = 2	0.32 × 0.14 × 0.12 mm