π–π Stacking in bis­(quinolinium) tetra­chloro­zincate dihydrate

The asymmetric unit of the title compound, (C₉H₈N)₂[ZnCl₄]·2H₂O, consists of one quinolinium cation, one-half of the [ZnCl₄]²⁻ anion and one water mol­ecule. The geometry around the Zn atom is approximately tetra­hedral, with the Zn atom lying on a twofold axis. The water mol­ecules hydrogen bond to the [ZnCl₄]²⁻ anions and the quinolinium cations, forming a two-dimensional network with the cations protruding on both sides of the network and stacking through π–π inter­actions with adjacent networks.

Key indicators

• Single-crystal X-ray study
• T = 294 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.049
• wR factor = 0.087
• Data-to-parameter ratio = 23.7

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT094_ALERT_2_C Ratio of Maximum / Minimum Residual Density ....       2.31
PLAT164_ALERT_4_C Nr. of Refined C-H H-Atoms in Heavy-At Struct...          7
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        Zn1
PLAT350_ALERT_3_C Short   C-H Bond (0.96A)   C5     -   H5     ...       0.84 Ang.
PLAT417_ALERT_2_C Short Inter D-H..H-D       H1     ..  H1A     ..       2.11 Ang.

Alert level G
ABSTM02_ALERT_3_G  The ratio of expected to reported Tmax/Tmin(RR') is < 0.90
            Tmin and Tmax reported:      0.664     0.820
            Tmin(prime) and Tmax expected:      0.715     0.758
            RR(prime) =      0.859
            Please check that your absorption correction is appropriate.

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

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

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Computing details

Data collection: SMART (Bruker, 1999); cell refinement: SMART; data reduction: SAINT-Plus (Bruker, 1999); program(s) used to solve structure: SHELXTL/PC (Sheldrick, 2000); program(s) used to refine structure: SHELXTL/PC; molecular graphics: Mercury (Version 1.3; Bruno et al., 2002) and PLATON (Spek, 2003); software used to prepare material for publication: enCIFer (Allen et al., 2004).

bis(quinolinium) tetrachlorozincate dihydrate

Crystal data

(C9H8N)2[ZnCl4]·2H2O	F(000) = 1024
Mr = 503.53	Dx = 1.566 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 4637 reflections
a = 11.7991 (9) Å	θ = 2.7–30.8°
b = 10.0206 (8) Å	µ = 1.67 mm^−1
c = 18.423 (1) Å	T = 294 K
β = 101.352 (2)°	Prism, colorless
V = 2135.6 (3) Å^3	0.20 × 0.19 × 0.17 mm
Z = 4

Data collection

Bruker SMART APEX CCD diffractometer	3867 independent reflections
Radiation source: fine-focus sealed tube	2469 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.064
Detector resolution: 0.661 pixels mm^-1	θmax = 32.6°, θmin = 2.3°
ω scans	h = −17→17
Absorption correction: analytical (SHELXTL/PC; Sheldrick, 1997)	k = −15→14
Tmin = 0.664, Tmax = 0.820	l = −27→27
14529 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)] = 0.049	Hydrogen site location: difference Fourier map
wR(F^2) = 0.087	All H-atom parameters refined
S = 1.01	w = 1/[σ^2(Fo^2) + (0.0233P)^2] where P = (Fo^2 + 2Fc^2)/3
3867 reflections	(Δ/σ)max = 0.001
163 parameters	Δρmax = 0.81 e Å^−3
0 restraints	Δρmin = −0.35 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
Zn1	0.0000	0.84499 (4)	0.2500	0.04038 (12)
Cl1	0.14736 (5)	0.71444 (7)	0.30876 (3)	0.06000 (19)
Cl2	0.07257 (5)	0.96958 (7)	0.16888 (4)	0.06256 (19)
O1	0.1511 (2)	0.4033 (3)	0.27512 (11)	0.0623 (5)
H1A	0.152 (3)	0.474 (4)	0.283 (2)	0.12 (2)*
H1B	0.216 (3)	0.382 (3)	0.278 (2)	0.113 (16)*
N1	0.06443 (18)	0.3469 (2)	0.39960 (11)	0.0467 (5)
H1	0.0950 (19)	0.366 (2)	0.3676 (12)	0.042 (7)*
C2	−0.0388 (2)	0.2931 (3)	0.39015 (14)	0.0532 (6)
H2	−0.0749 (16)	0.279 (2)	0.3393 (12)	0.041 (6)*
C3	−0.0876 (2)	0.2642 (3)	0.45034 (15)	0.0549 (6)
H3	−0.1615 (18)	0.224 (2)	0.4412 (12)	0.050 (7)*
C4	−0.0283 (2)	0.2919 (2)	0.51945 (14)	0.0499 (6)
H4	−0.0600 (17)	0.266 (2)	0.5582 (12)	0.045 (6)*
C5	0.1498 (2)	0.3786 (2)	0.60032 (13)	0.0517 (6)
H5	0.1227 (18)	0.354 (2)	0.6371 (12)	0.045 (6)*
C6	0.2566 (3)	0.4322 (3)	0.60668 (15)	0.0577 (7)
H6	0.298 (2)	0.451 (2)	0.6527 (14)	0.065 (8)*
C7	0.3015 (2)	0.4597 (3)	0.54364 (15)	0.0564 (6)
H7	0.378 (2)	0.497 (2)	0.5490 (13)	0.062 (7)*
C8	0.2401 (2)	0.4334 (2)	0.47476 (15)	0.0497 (6)
H8	0.2675 (18)	0.452 (2)	0.4336 (12)	0.052 (7)*
C9	0.12943 (18)	0.3769 (2)	0.46786 (11)	0.0394 (5)
C10	0.08235 (19)	0.3489 (2)	0.53011 (11)	0.0409 (5)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Zn1	0.0363 (2)	0.0478 (2)	0.0381 (2)	0.000	0.00961 (15)	0.000
Cl1	0.0557 (4)	0.0696 (4)	0.0524 (4)	0.0195 (3)	0.0048 (3)	0.0048 (3)
Cl2	0.0517 (4)	0.0730 (4)	0.0660 (4)	−0.0035 (3)	0.0192 (3)	0.0241 (3)
O1	0.0566 (13)	0.0834 (17)	0.0489 (11)	−0.0079 (11)	0.0155 (9)	−0.0028 (11)
N1	0.0594 (13)	0.0482 (12)	0.0348 (10)	0.0056 (10)	0.0146 (10)	0.0051 (9)
C2	0.0599 (16)	0.0510 (15)	0.0440 (14)	0.0009 (12)	−0.0011 (12)	0.0009 (11)
C3	0.0480 (14)	0.0556 (16)	0.0602 (17)	−0.0069 (12)	0.0082 (13)	0.0051 (12)
C4	0.0564 (15)	0.0505 (15)	0.0459 (14)	−0.0011 (11)	0.0179 (12)	0.0045 (11)
C5	0.0694 (18)	0.0519 (15)	0.0356 (13)	0.0008 (12)	0.0144 (12)	−0.0010 (11)
C6	0.0666 (18)	0.0522 (16)	0.0486 (15)	0.0007 (13)	−0.0024 (14)	−0.0061 (12)
C7	0.0474 (15)	0.0514 (15)	0.0681 (18)	−0.0015 (12)	0.0061 (13)	−0.0017 (13)
C8	0.0520 (15)	0.0476 (14)	0.0539 (15)	0.0034 (11)	0.0211 (12)	0.0043 (11)
C9	0.0482 (13)	0.0336 (11)	0.0371 (11)	0.0075 (9)	0.0101 (9)	0.0027 (8)
C10	0.0496 (12)	0.0370 (11)	0.0373 (11)	0.0054 (10)	0.0117 (10)	0.0021 (9)

Geometric parameters (Å, º)

Zn1—Cl2	2.2425 (6)	C4—C10	1.403 (3)
Zn1—Cl2^i	2.2425 (6)	C4—H4	0.91 (2)
Zn1—Cl1^i	2.2728 (6)	C5—C6	1.355 (4)
Zn1—Cl1	2.2728 (6)	C5—C10	1.410 (3)
O1—H1A	0.72 (4)	C5—H5	0.84 (2)
O1—H1B	0.78 (4)	C6—C7	1.395 (4)
N1—C2	1.312 (3)	C6—H6	0.91 (2)
N1—C9	1.371 (3)	C7—C8	1.357 (3)
N1—H1	0.77 (2)	C7—H7	0.97 (2)
C2—C3	1.377 (3)	C8—C9	1.406 (3)
C2—H2	0.96 (2)	C8—H8	0.90 (2)
C3—C4	1.355 (3)	C9—C10	1.398 (3)
C3—H3	0.94 (2)
Cl2—Zn1—Cl2^i	112.34 (4)	C6—C5—C10	120.7 (2)
Cl2—Zn1—Cl1^i	111.08 (2)	C6—C5—H5	122.8 (15)
Cl2^i—Zn1—Cl1^i	106.33 (2)	C10—C5—H5	116.2 (15)
Cl2—Zn1—Cl1	106.33 (2)	C5—C6—C7	120.4 (2)
Cl2^i—Zn1—Cl1	111.08 (2)	C5—C6—H6	118.9 (16)
Cl1^i—Zn1—Cl1	109.71 (4)	C7—C6—H6	120.7 (16)
H1A—O1—H1B	106 (4)	C8—C7—C6	121.3 (3)
C2—N1—C9	123.3 (2)	C8—C7—H7	119.1 (14)
C2—N1—H1	124.1 (17)	C6—C7—H7	119.5 (14)
C9—N1—H1	112.6 (17)	C7—C8—C9	118.6 (2)
N1—C2—C3	120.3 (2)	C7—C8—H8	122.2 (14)
N1—C2—H2	114.3 (12)	C9—C8—H8	119.2 (14)
C3—C2—H2	125.4 (12)	N1—C9—C10	117.9 (2)
C4—C3—C2	119.5 (2)	N1—C9—C8	120.9 (2)
C4—C3—H3	122.9 (13)	C10—C9—C8	121.2 (2)
C2—C3—H3	117.6 (13)	C9—C10—C4	118.4 (2)
C3—C4—C10	120.6 (2)	C9—C10—C5	117.8 (2)
C3—C4—H4	117.7 (14)	C4—C10—C5	123.8 (2)
C10—C4—H4	121.5 (14)

Symmetry code: (i) −x, y, −z+1/2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1	0.77 (2)	1.98 (2)	2.747 (3)	171 (2)
O1—H1B···Cl2^ii	0.78 (4)	2.65 (4)	3.288 (2)	140 (3)
O1—H1A···Cl1	0.72 (4)	2.46 (4)	3.181 (3)	178 (4)

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