Table 3. Experimental details.

	20 K	298 K model 1	298 K model 2
Crystal data
Chemical formula	2C2H6NO2 +·SO4 2−·C2H5NO2	2C2H6NO2 +·SO4 2−·C2H5NO2	2C2H6NO2 +·SO4 2−·C2H5NO2
M r	323.28	323.28	323.28
Crystal system, space group	Monoclinic, P21	Monoclinic, P21	Monoclinic, P21
Temperature (K)	20	298	298
a, b, c (Å)	9.3946 (8), 12.5338 (11), 5.6630 (4)	9.3910 (14), 12.6021 (18), 5.7125 (7)	9.3910 (14), 12.6021 (18), 5.7125 (7)
β (°)	110.500 (7)	110.306 (13)	110.306 (13)
V (Å3)	624.59 (9)	634.04 (16)	634.04 (16)
Z	2	2	2
Radiation type	Neutrons, λ = 1 Å	Neutrons, λ = 1 Å	Neutrons, λ = 1 Å
μ (mm−1)	0.49	0.49	0.49
Crystal size (mm)	2.80 × 2.80 × 2.80	2.80 × 2.80 × 2.80	2.80 × 2.80 × 2.80
Data collection
Diffractometer	Time-of-flight Laue-type single crystal neutron diffractometer	Time-of-flight Laue-type single crystal neutron diffractometer	Time-of-flight Laue-type single crystal neutron diffractometer
No. of measured, independent and observed [I > 2σ(I)] reflections	40510, 10169, 33150	14190, 3132, 10685	14190, 3132, 10685
(sin θ/λ)max (Å−1)	0.998	0.994	0.994
Refinement
R[F 2 > 2σ(F 2)], wR(F 2), S	0.073, 0.193, 1.04	0.080, 0.209, 1.05	0.080, 0.209, 1.05
No. of reflections	40510	14190	14190
No. of parameters	350	357	358
No. of restraints	1	1	8
H-atom treatment	All H-atom parameters refined	All H-atom parameters refined	All H-atom parameters refined
Δρmax, Δρmin (e Å−3)	3.87, −6.29	3.50, −6.06	1.50, −1.70
Absolute structure	Indeterminate for a neutron structure	Indeterminate for a neutron structure	Indeterminate for a neutron structure

Computer programs: STARGazer (Ohhara et al., 2009 ▸), SHELXL2018/3 (Sheldrick, 2015 ▸), Mercury (Macrae et al., 2020 ▸), PLATON (Spek, 2020 ▸) and publCIF (Westrip, 2010 ▸).