(I)	(II)	(III)	(IV)	(V)
Crystal data
Chemical formula	C11H17N2O+·C7H4ClO2 −	C11H17N2O+·C7H4BrO2 −	C11H17N2O+·C7H4IO2 −	C11H17N2O+·C7H4FO2 −	C11H17N2O+·C7H4ClO2 −
M r	348.82	393.27	440.27	332.37	348.82
Crystal system, space group	Triclinic, P	Triclinic, P	Triclinic, P	Monoclinic, C c	Monoclinic, P21/c
Temperature (K)	296	296	296	296	296
a, b, c (Å)	7.401 (1), 7.888 (1), 15.410 (3)	7.4313 (5), 7.9163 (5), 15.5212 (9)	7.1129 (4), 11.2722 (7), 12.5923 (8)	19.940 (1), 10.2705 (7), 9.0148 (7)	7.9974 (8), 27.611 (2), 8.5972 (9)
α, β, γ (°)	100.28 (2), 94.40 (1), 94.14 (1)	101.565 (5), 94.780 (5), 92.691 (5)	69.852 (5), 74.681 (5), 79.121 (5)	90, 109.663 (8), 90	90, 106.40 (1), 90
V (Å3)	879.2 (2)	889.54 (10)	908.82 (10)	1738.5 (2)	1821.2 (3)
Z	2	2	2	4	4
Radiation type	Mo Kα	Mo Kα	Mo Kα	Mo Kα	Mo Kα
μ (mm−1)	0.24	2.33	1.78	0.09	0.23
Crystal size (mm)	0.44 × 0.28 × 0.16	0.42 × 0.42 × 0.12	0.48 × 0.24 × 0.14	0.48 × 0.36 × 0.22	0.48 × 0.20 × 0.12
Data collection
Diffractometer	Oxford Diffraction Xcalibur with Sapphire CCD	Oxford Diffraction Xcalibur with Sapphire CCD	Oxford Diffraction Xcalibur with Sapphire CCD	Oxford Diffraction Xcalibur with Sapphire CCD	Oxford Diffraction Xcalibur with Sapphire CCD
Absorption correction	Multi-scan (CrysAlis RED; Oxford Diffraction, 2009 ▸)	Multi-scan (CrysAlis RED; Oxford Diffraction, 2009 ▸)	Multi-scan (CrysAlis RED; Oxford Diffraction, 2009 ▸)	Multi-scan (CrysAlis RED; Oxford Diffraction, 2009 ▸)	Multi-scan (CrysAlis RED; Oxford Diffraction, 2009 ▸)
T min, T max	0.884, 0.963	0.258, 0.756	0.534, 0.779	0.884, 0.963	0.747, 0.973
No. of measured, independent and observed [I > 2σ(I)] reflections	6241, 3763, 2318	5996, 3739, 2989	6342, 3897, 3203	6204, 3343, 2786	13275, 3410, 2060
R int	0.019	0.018	0.012	0.012	0.030
(sin θ/λ)max (Å−1)	0.650	0.652	0.660	0.658	0.607
Refinement
R[F 2 > 2σ(F 2)], wR(F 2), S	0.053, 0.131, 1.01	0.043, 0.115, 1.05	0.026, 0.065, 1.02	0.036, 0.100, 1.03	0.067, 0.216, 1.03
No. of reflections	3763	3739	3897	3343	3410
No. of parameters	224	224	224	256	223
No. of restraints	0	0	0	25	0
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement	H atoms treated by a mixture of independent and constrained refinement	H atoms treated by a mixture of independent and constrained refinement	H atoms treated by a mixture of independent and constrained refinement	H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)	0.19, −0.27	0.84, −0.55	0.52, −0.70	0.24, −0.14	1.15, −0.30
Absolute structure	–	–	–	Flack x determined using 1089 quotients [(I +)−(I −)]/[(I +)+(I −)] (Parsons et al., 2013 ▸)	–
Absolute structure parameter	–	–	–	0.2 (3)	–