cis-Dichloro­bis[2-(2-pyrid­yl)-1H-imidazole-κN³]zinc(II) hemihydrate

In the title mononuclear zinc complex, [ZnCl₂(C₈H₇N₃)₂]·0.5H₂O, the Zn atom is located on a twofold axis and has a slightly distorted octa­hedral geometry consisting of four N atoms from two 2-(2-pyrid­yl)imidazole ligands and two Cl⁻ anions. The complex mol­ecules are connected through inter­molecular hydrogen bonds, forming a two-dimensional layer structure.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• Disorder in solvent or counterion
• R factor = 0.028
• wR factor = 0.091
• Data-to-parameter ratio = 17.1

checkCIF/PLATON results

No syntax errors found





Alert level C
PLAT041_ALERT_1_C Calc. and Rep. SumFormula Strings    Differ ....          ?
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT045_ALERT_1_C Calculated and Reported Z Differ by ............       0.50 Ratio
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       2.91
PLAT076_ALERT_1_C Occupancy       0.50 less than 1.0 for Sp.pos  .        O1W
PLAT147_ALERT_1_C su on Symmetry Constrained Cell Angle(s) .......          ?
PLAT302_ALERT_4_C Anion/Solvent Disorder .........................      50.00 Perc.

Alert level G
FORMU01_ALERT_1_G  There is a discrepancy between the atom counts in the
            _chemical_formula_sum and _chemical_formula_moiety. This is
            usually due to the moiety formula being in the wrong format.
            Atom count from _chemical_formula_sum:   C16 H15 Cl2 N6 O0.5 Zn1
            Atom count from _chemical_formula_moiety:C16 H16 Cl2 N6 O0.5 Zn1
ABSTM02_ALERT_3_G  When printed, the submitted absorption T values will be
            replaced by the scaled T values. Since the ratio of scaled T's
            is identical to the ratio of reported T values, the scaling
            does not imply a change to the absorption corrections used in
            the study.
            Ratio of Tmax expected/reported      2.911
            Tmax scaled      0.635 Tmin scaled      0.611
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        293 K

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

   8 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
   2 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL-Plus (Sheldrick, 1990); software used to prepare material for publication: SHELXL97.

cis-Dichlorobis[2-(2-pyridyl)-1H-imidazole-κN³]zinc(II) hemihydrate

Crystal data

[ZnCl2(C8H7N3)2]·0.5H2O	F(000) = 884
Mr = 435.62	Dx = 1.557 Mg m^−3
Orthorhombic, Pnna	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2a 2bc	Cell parameters from 1500 reflections
a = 9.279 (5) Å	θ = 2.1–28.3°
b = 16.055 (5) Å	µ = 1.62 mm^−1
c = 12.474 (5) Å	T = 293 K
V = 1858.3 (14) Å^3	Block, colorless
Z = 4	0.32 × 0.29 × 0.28 mm

Data collection

Bruker APEX CCD area-detector diffractometer	2222 independent reflections
Radiation source: fine-focus sealed tube	1740 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.049
φ and ω scans	θmax = 28.3°, θmin = 2.1°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −9→12
Tmin = 0.210, Tmax = 0.218	k = −21→13
10539 measured reflections	l = −15→16

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.028	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.091	w = 1/[σ^2(Fo^2) + (0.0581P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 1.05	(Δ/σ)max = 0.001
2222 reflections	Δρmax = 0.40 e Å^−3
130 parameters	Δρmin = −0.18 e Å^−3
3 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0031 (6)

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	Occ. (<1)
C1	0.6967 (2)	0.10776 (12)	0.27670 (17)	0.0531 (5)
H1	0.7205	0.1076	0.3491	0.064*
C2	0.5880 (3)	0.05656 (15)	0.24238 (16)	0.0616 (6)
H2	0.5399	0.0220	0.2903	0.074*
C3	0.5513 (2)	0.05737 (13)	0.13530 (19)	0.0685 (6)
H3	0.4762	0.0243	0.1104	0.082*
C4	0.6268 (2)	0.10759 (11)	0.06517 (17)	0.0590 (5)
H4	0.6056	0.1078	−0.0077	0.071*
C5	0.73536 (17)	0.15782 (10)	0.10670 (14)	0.0430 (4)
C6	0.82012 (18)	0.21589 (11)	0.04298 (13)	0.0420 (4)
C7	0.9724 (2)	0.31290 (13)	0.00626 (15)	0.0533 (5)
H7	1.0438	0.3531	0.0136	0.064*
C8	0.9047 (2)	0.29267 (14)	−0.08702 (15)	0.0593 (5)
H8	0.9205	0.3162	−0.1541	0.071*
N1	0.91890 (17)	0.26482 (9)	0.08722 (13)	0.0430 (4)
N2	0.80971 (18)	0.23158 (11)	−0.06266 (13)	0.0525 (4)
N3	0.77016 (15)	0.15796 (9)	0.21100 (12)	0.0431 (3)
Cl1	1.12895 (5)	0.36368 (3)	0.26218 (3)	0.04627 (15)
Zn1	0.95416 (3)	0.2500	0.2500	0.04107 (14)
O1W	0.2500	0.5000	0.0704 (4)	0.1045 (17)	0.50
H5	0.752 (2)	0.2060 (14)	−0.1113 (16)	0.068 (6)*
H1A	0.178 (8)	0.492 (6)	0.031 (7)	0.102*	0.25
H1B	0.257 (10)	0.457 (4)	0.109 (7)	0.102*	0.25

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0581 (12)	0.0482 (10)	0.0530 (10)	−0.0007 (9)	0.0088 (9)	0.0032 (9)
C2	0.0619 (13)	0.0469 (12)	0.0759 (16)	−0.0093 (10)	0.0139 (10)	0.0040 (9)
C3	0.0652 (14)	0.0562 (12)	0.0842 (16)	−0.0181 (10)	−0.0028 (11)	−0.0016 (12)
C4	0.0605 (12)	0.0550 (11)	0.0614 (13)	−0.0126 (10)	−0.0107 (9)	−0.0025 (10)
C5	0.0402 (9)	0.0400 (9)	0.0488 (9)	0.0019 (7)	−0.0022 (7)	−0.0016 (7)
C6	0.0412 (9)	0.0446 (9)	0.0403 (9)	0.0014 (8)	−0.0067 (7)	−0.0025 (8)
C7	0.0521 (11)	0.0610 (12)	0.0469 (10)	−0.0120 (9)	−0.0055 (8)	0.0099 (9)
C8	0.0584 (11)	0.0762 (14)	0.0431 (10)	−0.0123 (11)	−0.0070 (9)	0.0149 (10)
N1	0.0435 (8)	0.0486 (8)	0.0368 (8)	−0.0049 (6)	−0.0039 (7)	0.0026 (6)
N2	0.0496 (9)	0.0666 (10)	0.0413 (9)	−0.0077 (7)	−0.0107 (7)	0.0013 (8)
N3	0.0430 (8)	0.0424 (8)	0.0438 (7)	−0.0004 (6)	0.0024 (6)	−0.0010 (7)
Cl1	0.0479 (3)	0.0454 (3)	0.0455 (3)	−0.00158 (18)	−0.00588 (17)	−0.00051 (17)
Zn1	0.0431 (2)	0.0483 (2)	0.03185 (19)	0.000	0.000	−0.00009 (11)
O1W	0.144 (6)	0.080 (3)	0.089 (4)	0.019 (3)	0.000	0.000

Geometric parameters (Å, º)

C1—N3	1.336 (2)	C7—N1	1.365 (2)
C1—C2	1.370 (3)	C7—H7	0.9300
C1—H1	0.9300	C8—N2	1.353 (3)
C2—C3	1.378 (3)	C8—H8	0.9300
C2—H2	0.9300	N1—Zn1	2.0704 (18)
C3—C4	1.380 (3)	N2—H5	0.91 (2)
C3—H3	0.9300	N3—Zn1	2.3099 (16)
C4—C5	1.391 (2)	Cl1—Zn1	2.4463 (9)
C4—H4	0.9300	Zn1—N1^i	2.0704 (18)
C5—N3	1.340 (2)	Zn1—N3^i	2.3099 (16)
C5—C6	1.456 (2)	Zn1—Cl1^i	2.4463 (9)
C6—N1	1.327 (2)	O1W—H1A	0.841 (10)
C6—N2	1.345 (2)	O1W—H1B	0.842 (10)
C7—C8	1.362 (3)
N3—C1—C2	123.08 (19)	C6—N1—Zn1	116.68 (12)
N3—C1—H1	118.5	C7—N1—Zn1	137.16 (13)
C2—C1—H1	118.5	C6—N2—C8	108.00 (16)
C1—C2—C3	118.6 (2)	C6—N2—H5	127.7 (13)
C1—C2—H2	120.7	C8—N2—H5	124.2 (13)
C3—C2—H2	120.7	C1—N3—C5	118.12 (16)
C2—C3—C4	119.6 (2)	C1—N3—Zn1	129.32 (13)
C2—C3—H3	120.2	C5—N3—Zn1	112.55 (11)
C4—C3—H3	120.2	N1^i—Zn1—N1	161.81 (9)
C3—C4—C5	118.04 (19)	N1^i—Zn1—N3	90.93 (6)
C3—C4—H4	121.0	N1—Zn1—N3	75.53 (6)
C5—C4—H4	121.0	N1^i—Zn1—N3^i	75.53 (6)
N3—C5—C4	122.49 (16)	N1—Zn1—N3^i	90.93 (6)
N3—C5—C6	113.50 (15)	N3—Zn1—N3^i	84.68 (8)
C4—C5—C6	124.01 (16)	N1^i—Zn1—Cl1	97.45 (4)
N1—C6—N2	110.25 (17)	N1—Zn1—Cl1	94.59 (4)
N1—C6—C5	121.67 (15)	N3—Zn1—Cl1	168.64 (4)
N2—C6—C5	128.03 (16)	N3^i—Zn1—Cl1	89.98 (5)
C8—C7—N1	109.24 (17)	N1^i—Zn1—Cl1^i	94.59 (4)
C8—C7—H7	125.4	N1—Zn1—Cl1^i	97.45 (4)
N1—C7—H7	125.4	N3—Zn1—Cl1^i	89.98 (5)
N2—C8—C7	106.35 (16)	N3^i—Zn1—Cl1^i	168.64 (4)
N2—C8—H8	126.8	Cl1—Zn1—Cl1^i	96.95 (4)
C7—C8—H8	126.8	H1A—O1W—H1B	105.7 (17)
C6—N1—C7	106.16 (15)
N3—C1—C2—C3	−0.7 (3)	C6—C5—N3—C1	178.86 (15)
C1—C2—C3—C4	1.7 (3)	C4—C5—N3—Zn1	−179.55 (14)
C2—C3—C4—C5	−1.9 (3)	C6—C5—N3—Zn1	−0.56 (17)
C3—C4—C5—N3	1.1 (3)	C7—N1—Zn1—N1^i	135.6 (2)
C3—C4—C5—C6	−177.77 (17)	C6—N1—Zn1—N3	−2.43 (13)
N3—C5—C6—N1	−1.6 (2)	C7—N1—Zn1—N3	178.6 (2)
C4—C5—C6—N1	177.36 (18)	C6—N1—Zn1—N3^i	−86.69 (14)
N3—C5—C6—N2	−178.63 (17)	C7—N1—Zn1—N3^i	94.3 (2)
C4—C5—C6—N2	0.3 (3)	C6—N1—Zn1—Cl1	−176.75 (13)
N1—C7—C8—N2	−0.3 (2)	C7—N1—Zn1—Cl1	4.2 (2)
N2—C6—N1—C7	0.0 (2)	C6—N1—Zn1—Cl1^i	85.62 (13)
C5—C6—N1—C7	−177.53 (16)	C7—N1—Zn1—Cl1^i	−93.4 (2)
N2—C6—N1—Zn1	−179.33 (12)	C1—N3—Zn1—N1^i	−10.03 (15)
C5—C6—N1—Zn1	3.2 (2)	C5—N3—Zn1—N1^i	169.30 (12)
C8—C7—N1—C6	0.2 (2)	C1—N3—Zn1—N1	−177.75 (16)
C8—C7—N1—Zn1	179.26 (15)	C5—N3—Zn1—N1	1.59 (11)
N1—C6—N2—C8	−0.1 (2)	C1—N3—Zn1—N3^i	−85.41 (15)
C5—C6—N2—C8	177.17 (18)	C5—N3—Zn1—N3^i	93.93 (12)
C7—C8—N2—C6	0.2 (2)	C1—N3—Zn1—Cl1	−147.68 (16)
C2—C1—N3—C5	−0.1 (3)	C5—N3—Zn1—Cl1	31.7 (3)
C2—C1—N3—Zn1	179.23 (16)	C1—N3—Zn1—Cl1^i	84.55 (15)
C4—C5—N3—C1	−0.1 (3)	C5—N3—Zn1—Cl1^i	−96.11 (11)

Symmetry code: (i) x, −y+1/2, −z+1/2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H5···Cl1^ii	0.91 (2)	2.25 (2)	3.151 (2)	174.3 (18)

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