catena-Poly[[(1H-benzimidazole-κN)iodo­mercury(II)]-μ-iodo]

In the title polymeric complex, [HgI₂(C₇H₆N₂)]_n, the Hg^II atom is coordinated by one benzimidazole (bzim) and three I⁻ anions with a distorted tetra­hedral geometry; one I⁻ anion is in a monodentate coordination mode and the other two are bridging. The two bridging Hg—I bond distances differ significantly [2.7420 (7) and 3.0543 (7) Å]. The face-to-face separation of 3.31 (3) Å between the mean planes of parallel bzim ligands and the partially overlapped arrangement indicate the existence of π–π stacking.

Key indicators

• Single-crystal X-ray study
• T = 295 K
• Mean [sigma](C-C) = 0.013 Å
• R factor = 0.033
• wR factor = 0.067
• Data-to-parameter ratio = 17.9

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT342_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...         13

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   1 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
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: PROCESS-AUTO (Rigaku, 1998); cell refinement: PROCESS-AUTO; data reduction: Crystal Structure (Rigaku, 2002); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

catena-Poly[[(1H-benzimidazole-κN)iodomercury(II)]-µ-iodo]

Crystal data

[HgI2(C7H6N2)]	F(000) = 992
Mr = 572.53	Dx = 3.489 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71069 Å
Hall symbol: -P 2yn	Cell parameters from 7029 reflections
a = 4.4079 (4) Å	θ = 2.0–25.0°
b = 13.3559 (11) Å	µ = 19.74 mm^−1
c = 18.6196 (16) Å	T = 295 K
β = 96.136 (12)°	Prism, yellow
V = 1089.88 (16) Å^3	0.12 × 0.08 × 0.06 mm
Z = 4

Data collection

Rigaku R-AXIS RAPID diffractometer	1955 independent reflections
Radiation source: fine-focus sealed tube	1768 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.031
Detector resolution: 10.00 pixels mm^-1	θmax = 25.2°, θmin = 1.9°
ω scans	h = −5→4
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	k = −16→16
Tmin = 0.095, Tmax = 0.298	l = −22→22
7910 measured reflections

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)] = 0.033	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.067	H-atom parameters constrained
S = 1.20	w = 1/[σ^2(Fo^2) + (0.0191P)^2 + 7.8058P] where P = (Fo^2 + 2Fc^2)/3
1955 reflections	(Δ/σ)max = 0.001
109 parameters	Δρmax = 1.27 e Å^−3
0 restraints	Δρmin = −1.41 e Å^−3

Special details

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

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

	x	y	z	Uiso*/Ueq
Hg	0.68340 (9)	0.31304 (3)	0.624594 (19)	0.04999 (13)
I1	0.56356 (15)	0.14760 (4)	0.69303 (3)	0.05022 (17)
I2	0.14354 (12)	0.45207 (4)	0.63948 (3)	0.04185 (15)
N1	0.4151 (17)	0.3140 (5)	0.3876 (4)	0.0466 (18)
H1	0.3093	0.3373	0.3498	0.056*
N3	0.6027 (16)	0.2985 (5)	0.5016 (3)	0.0405 (16)
C2	0.409 (2)	0.3472 (7)	0.4557 (5)	0.046 (2)
H2	0.2830	0.3984	0.4688	0.055*
C4	0.952 (2)	0.1537 (7)	0.4823 (5)	0.047 (2)
H4	1.0317	0.1460	0.5303	0.056*
C5	1.039 (2)	0.0925 (7)	0.4275 (6)	0.056 (2)
H5	1.1810	0.0421	0.4393	0.067*
C6	0.920 (2)	0.1041 (8)	0.3562 (6)	0.059 (3)
H6	0.9882	0.0625	0.3212	0.070*
C7	0.707 (2)	0.1748 (7)	0.3362 (5)	0.052 (2)
H7	0.6236	0.1813	0.2884	0.062*
C8	0.6204 (19)	0.2362 (7)	0.3892 (4)	0.0405 (19)
C9	0.7379 (18)	0.2275 (6)	0.4602 (4)	0.0375 (18)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Hg	0.0642 (3)	0.0485 (2)	0.0374 (2)	−0.00778 (18)	0.00582 (17)	0.00346 (15)
I1	0.0567 (4)	0.0430 (3)	0.0512 (4)	−0.0052 (3)	0.0066 (3)	0.0057 (3)
I2	0.0374 (3)	0.0370 (3)	0.0510 (3)	0.0009 (2)	0.0040 (3)	0.0012 (2)
N1	0.052 (4)	0.051 (5)	0.034 (4)	−0.001 (4)	−0.008 (3)	0.011 (3)
N3	0.051 (4)	0.042 (4)	0.027 (3)	−0.008 (3)	−0.004 (3)	−0.001 (3)
C2	0.053 (5)	0.040 (5)	0.042 (5)	−0.001 (4)	−0.003 (4)	0.006 (4)
C4	0.047 (5)	0.049 (5)	0.044 (5)	−0.008 (4)	0.004 (4)	0.005 (4)
C5	0.054 (6)	0.050 (6)	0.067 (7)	0.000 (5)	0.017 (5)	0.007 (5)
C6	0.067 (7)	0.055 (6)	0.056 (6)	−0.018 (5)	0.017 (5)	−0.007 (5)
C7	0.062 (6)	0.063 (6)	0.032 (5)	−0.017 (5)	0.010 (5)	0.000 (4)
C8	0.040 (5)	0.049 (5)	0.031 (4)	−0.011 (4)	−0.001 (4)	0.004 (4)
C9	0.035 (4)	0.037 (4)	0.039 (4)	−0.009 (4)	−0.002 (4)	0.006 (4)

Geometric parameters (Å, º)

Hg—I1	2.6322 (7)	C4—C5	1.392 (13)
Hg—I2^i	2.7420 (7)	C4—C9	1.396 (12)
Hg—I2	3.0543 (7)	C4—H4	0.9300
I2—Hg^ii	2.7420 (7)	C5—C6	1.382 (14)
Hg—N3	2.289 (6)	C5—H5	0.9300
N1—C2	1.347 (11)	C6—C7	1.355 (14)
N1—C8	1.376 (11)	C6—H6	0.9300
N1—H1	0.8600	C7—C8	1.369 (12)
N3—C2	1.313 (11)	C7—H7	0.9300
N3—C9	1.395 (11)	C8—C9	1.372 (11)
C2—H2	0.9300
I1—Hg—I2	105.53 (2)	C5—C4—H4	122.3
I1—Hg—I2^i	134.76 (2)	C9—C4—H4	122.3
I1—Hg—N3	113.29 (17)	C6—C5—C4	122.2 (10)
I2—Hg—N3	95.93 (18)	C6—C5—H5	118.9
N3—Hg—I2^i	101.12 (17)	C4—C5—H5	118.9
I2^i—Hg—I2	98.87 (2)	C7—C6—C5	121.5 (10)
Hg^ii—I2—Hg	98.87 (2)	C7—C6—H6	119.3
C2—N1—C8	107.9 (7)	C5—C6—H6	119.3
C2—N1—H1	126.1	C6—C7—C8	117.2 (9)
C8—N1—H1	126.1	C6—C7—H7	121.4
C2—N3—C9	105.3 (7)	C8—C7—H7	121.4
C2—N3—Hg	129.0 (6)	C7—C8—C9	122.5 (9)
C9—N3—Hg	125.5 (5)	C7—C8—N1	132.2 (8)
N3—C2—N1	111.8 (8)	C9—C8—N1	105.3 (7)
N3—C2—H2	124.1	C8—C9—N3	109.6 (7)
N1—C2—H2	124.1	C8—C9—C4	121.2 (8)
C5—C4—C9	115.4 (8)	N3—C9—C4	129.2 (8)

Symmetry codes: (i) x+1, y, z; (ii) x−1, y, z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···I1^iii	0.86	3.01	3.820 (7)	158

Symmetry code: (iii) x−1/2, −y+1/2, z−1/2.