4-(4-Pyrid­yl)pyridinium triiodide

The title compound, C₁₀H₉N₂⁺·I₃⁻, contains monoprotonated 4,4′-bipyridinium cations and triiodide anions. The cations assemble into infinite chains by way of N—H...N hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.007 Å
• R factor = 0.036
• wR factor = 0.079
• Data-to-parameter ratio = 38.2

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT094_ALERT_2_C Ratio of Maximum / Minimum Residual Density ....       2.27
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.42

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   2 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: CrysAlis CCD (Oxford Diffraction, 2003); cell refinement: CrysAlis RED (Oxford Diffraction, 2003); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1999); software used to prepare material for publication: SHELXL97.

4-(4-Pyridyl)pyridinium triiodide

Crystal data

C10H9N2^+·I3^−	Z = 2
Mr = 537.89	F(000) = 484
Triclinic, P1	Dx = 2.649 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.8399 (9) Å	Cell parameters from 3150 reflections
b = 9.6529 (8) Å	θ = 3.6–36.6°
c = 9.7154 (7) Å	µ = 6.93 mm^−1
α = 107.743 (7)°	T = 100 K
β = 104.709 (7)°	Prism, yellow–brown
γ = 110.791 (8)°	0.12 × 0.06 × 0.06 mm
V = 674.38 (13) Å^3

Data collection

Kuma KM-4-CCD diffractometer	5192 independent reflections
Radiation source: fine-focus sealed tube	3429 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.050
ω scans	θmax = 36.6°, θmin = 3.6°
Absorption correction: numerical (CrysAlis RED; Oxford Diffraction, 2003)	h = −14→11
Tmin = 0.490, Tmax = 0.681	k = −15→15
10483 measured reflections	l = −14→16

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.036	Hydrogen site location: difmap and geom
wR(F^2) = 0.079	H-atom parameters constrained
S = 0.92	w = 1/[σ^2(Fo^2) + (0.0339P)^2] where P = (Fo^2 + 2Fc^2)/3
5192 reflections	(Δ/σ)max < 0.001
136 parameters	Δρmax = 3.20 e Å^−3
0 restraints	Δρmin = −1.41 e Å^−3

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
N1	0.7381 (5)	0.5423 (4)	0.0037 (4)	0.0161 (8)
H1A	0.7422	0.4403	0.0007	0.019*
N2	0.7301 (5)	1.2664 (4)	−0.0020 (4)	0.0150 (7)
C1	0.8532 (6)	0.6894 (5)	0.1275 (5)	0.0173 (9)
H1	0.9361	0.6946	0.2157	0.021*
C2	0.8532 (6)	0.8338 (5)	0.1291 (5)	0.0167 (9)
H2	0.9356	0.9369	0.2172	0.020*
C3	0.6215 (6)	0.5334 (5)	−0.1223 (5)	0.0163 (8)
H3	0.5424	0.4290	−0.2099	0.020*
C4	0.6135 (6)	0.6719 (5)	−0.1282 (5)	0.0157 (8)
H4	0.5293	0.6629	−0.2182	0.019*
C5	0.6827 (6)	0.9944 (5)	−0.1419 (5)	0.0162 (8)
H5	0.6492	0.9060	−0.2398	0.019*
C6	0.6885 (6)	1.1418 (5)	−0.1375 (5)	0.0165 (8)
H6	0.6624	1.1542	−0.2327	0.020*
C7	0.7686 (6)	1.1095 (5)	0.1399 (5)	0.0148 (8)
H7	0.7963	1.1014	0.2373	0.018*
C8	0.7689 (6)	1.2505 (5)	0.1342 (5)	0.0157 (8)
H8	0.7975	1.3397	0.2294	0.019*
C9	0.7262 (6)	0.9774 (5)	−0.0019 (5)	0.0128 (8)
C10	0.7311 (5)	0.8257 (5)	0.0002 (5)	0.0137 (8)
I1	0.23357 (4)	0.32624 (3)	0.47599 (3)	0.01487 (6)
I2	0.26742 (4)	0.05081 (3)	0.52739 (3)	0.01641 (7)
I3	0.22289 (4)	0.61395 (3)	0.43887 (3)	0.01844 (7)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.026 (2)	0.0093 (15)	0.0189 (18)	0.0115 (15)	0.0100 (15)	0.0085 (14)
N2	0.0185 (17)	0.0099 (15)	0.0161 (17)	0.0061 (13)	0.0058 (14)	0.0068 (13)
C1	0.021 (2)	0.0152 (19)	0.016 (2)	0.0105 (17)	0.0020 (16)	0.0090 (15)
C2	0.023 (2)	0.0113 (18)	0.0149 (19)	0.0081 (16)	0.0060 (16)	0.0060 (15)
C3	0.021 (2)	0.0097 (17)	0.0150 (19)	0.0066 (16)	0.0041 (16)	0.0043 (14)
C4	0.019 (2)	0.0130 (18)	0.0152 (19)	0.0096 (16)	0.0046 (16)	0.0065 (15)
C5	0.023 (2)	0.0160 (19)	0.0140 (19)	0.0131 (17)	0.0072 (16)	0.0083 (15)
C6	0.021 (2)	0.0155 (19)	0.015 (2)	0.0114 (17)	0.0050 (16)	0.0076 (16)
C7	0.020 (2)	0.0094 (17)	0.0134 (18)	0.0066 (15)	0.0041 (15)	0.0047 (14)
C8	0.020 (2)	0.0124 (18)	0.0143 (19)	0.0094 (16)	0.0066 (16)	0.0044 (14)
C9	0.0163 (18)	0.0063 (16)	0.0178 (19)	0.0067 (15)	0.0066 (15)	0.0064 (14)
C10	0.016 (2)	0.0145 (18)	0.016 (2)	0.0098 (16)	0.0064 (16)	0.0101 (15)
I1	0.01617 (13)	0.01307 (11)	0.01417 (12)	0.00690 (10)	0.00475 (10)	0.00561 (9)
I2	0.02006 (14)	0.01468 (13)	0.01560 (13)	0.00868 (10)	0.00629 (10)	0.00807 (10)
I3	0.02265 (15)	0.01595 (13)	0.02152 (15)	0.01120 (11)	0.00981 (11)	0.01070 (11)

Geometric parameters (Å, º)

N1—C3	1.342 (6)	C4—H4	0.9500
N1—C1	1.345 (5)	C5—C6	1.392 (6)
N1—H1A	0.9902	C5—C9	1.393 (6)
N2—C6	1.338 (5)	C5—H5	0.9500
N2—C8	1.350 (6)	C6—H6	0.9500
C1—C2	1.390 (6)	C7—C8	1.378 (6)
C1—H1	0.9500	C7—C9	1.412 (5)
C2—C10	1.391 (6)	C7—H7	0.9500
C2—H2	0.9500	C8—H8	0.9500
C3—C4	1.382 (6)	C9—C10	1.486 (5)
C3—H3	0.9500	I1—I3	2.9380 (5)
C4—C10	1.399 (6)	I1—I2	2.9505 (5)
C3—N1—C1	119.9 (4)	C9—C5—H5	120.2
C3—N1—H1A	118.8	N2—C6—C5	121.5 (4)
C1—N1—H1A	121.1	N2—C6—H6	119.3
C6—N2—C8	119.7 (4)	C5—C6—H6	119.3
N1—C1—C2	121.3 (4)	C8—C7—C9	118.7 (4)
N1—C1—H1	119.3	C8—C7—H7	120.7
C2—C1—H1	119.3	C9—C7—H7	120.7
C1—C2—C10	119.2 (4)	N2—C8—C7	122.3 (4)
C1—C2—H2	120.4	N2—C8—H8	118.9
C10—C2—H2	120.4	C7—C8—H8	118.9
N1—C3—C4	121.8 (4)	C5—C9—C7	118.3 (4)
N1—C3—H3	119.1	C5—C9—C10	121.4 (4)
C4—C3—H3	119.1	C7—C9—C10	120.3 (4)
C3—C4—C10	119.0 (4)	C2—C10—C4	118.7 (4)
C3—C4—H4	120.5	C2—C10—C9	120.7 (4)
C10—C4—H4	120.5	C4—C10—C9	120.6 (4)
C6—C5—C9	119.5 (4)	I3—I1—I2	176.443 (13)
C6—C5—H5	120.2