Table 3. Experimental details.

Crystal data
Chemical formula	[Co(C6H6N2O)2(H2O)4](C4H4O4)
M r	491.32
Crystal system, space group	Monoclinic, P21/c
Temperature (K)	296
a, b, c (Å)	9.6757 (8), 10.0381 (8), 11.4947 (10)
β (°)	112.489 (6)
V (Å3)	1031.53 (15)
Z	2
Radiation type	Mo Kα
μ (mm−1)	0.89
Crystal size (mm)	0.68 × 0.49 × 0.37
Data collection
Diffractometer	Stoe IPDS 2
Absorption correction	Integration (X-RED32; Stoe & Cie, 2002 ▸)
T min, T max	0.664, 0.770
No. of measured, independent and observed [I > 2σ(I)] reflections	5748, 2125, 1709
R int	0.033
(sin θ/λ)max (Å−1)	0.628
Refinement
R[F 2 > 2σ(F 2)], wR(F 2), S	0.034, 0.087, 1.02
No. of reflections	2125
No. of parameters	166
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)	0.28, −0.38

Computer programs: X-AREA and X-RED32 (Stoe & Cie, 2002 ▸), SHELXS97 (Sheldrick, 2008 ▸), SHELXL2017 (Sheldrick, 2015 ▸), ORTEP-3 for Windows (Farrugia, 2012 ▸), Mercury (Macrae et al., 2008 ▸) and PLATON (Spek, 2009 ▸).