Synthesis, crystal structure and thermal properties of catena-poly[[[bis­(2,3-di­methyl­pyrazine-κN¹)cadmium(II)]-di-μ-chlorido] monohydrate]

In the crystal structure of the title compound, the cadmium cations are linked by μ-1,1 bridging chloride anions into chains that are additionally connected by O—H⋯N hydrogen bonding via the water mol­ecules of crystallization into layers.

Abstract

The title compound, {[CdCl₂(C₆H₈N₂)₂]·H₂O}_n (C₆H₈N₂ = 2,3-di­methyl­pyrazine) was prepared by the reaction of cadmium chloride with 2,3-di­methyl­pyrazine in water. The asymmetric unit consists of two crystallographically independent cadmium cations that are situated on a twofold rotation axis, two crystallographically independent chloride anions and 2,3-di­methyl­pyrazine ligands as well as one water mol­ecule that are all located in general positions. The cadmium cations are octa­hedrally coordinated by two terminally N-bonded 2,3-di­methyl­pyrazine ligands and four chloride anions and are linked by pairs of μ-1,1 bridging chloride anions into chains that propagate in the crystallographic b-axis direction. These chains are connected into layers via the water mol­ecule of crystallization by inter­chain O—H⋯N hydrogen bonding. Powder X-ray diffraction (PXRD) indicates that a pure phase has been obtained. Thermogravimetry (TG) coupled to differential thermal analysis (DTA) indicates that the water mol­ecules are removed in the first step and that the 2,3-di­methyl­pyrazine ligands are lost in the subsequent two steps, leading to a compound with the composition [CdCl₂(C₆H₈N₂)].

1. Chemical context

The crystal structures of transition-metal halide and pseudohalide coordination compounds are characterized by a large structural variability because the metal cations can be linked by bridging halide anions into metal-halide substructures of different dimensionality (Kromp & Sheldrick, 1999 ▸; Peng et al., 2010 ▸; Li et al., 2005 ▸; Näther et al., 2002 ▸). This also leads to compounds of different stoichiometry in which the ratio between the metal halide and the coligand is different. In this context, thermal decomposition of coligand-rich compounds are useful to detect possible coligand-deficient compounds as inter­mediates because in several cases the coligands were removed in separate steps before a transformation into the pure metal halides is observed (Näther et al., 2001 ▸; Näther & Jess, 2001 ▸).

In the course of our systematic work, we reported new cadmium halide coordination compounds with 2,3-di­methyl­pyrazine (C₆H₈N₂) as ligand. With CdI₂ we obtained two compounds with the compositions CdI₂(C₆H₈N₂)₂ and CdI₂(C₆H₈N₂) (Näther, 2026a ▸). In both compounds the cadmium cations are tetra­hedrally coordinated, leading to discrete complexes in the 2,3-di­methyl­pyrazine-rich compound and which are linked into chains by the coligands in the 2,3-di­methyl­pyrazine-deficient compound. This is surprising because, in most cases, cadmium prefers an octa­hedral coordination and in this case one would expect the formation of CdI₂ chains built up of CdI₄N₂ octa­hedra linked by common iodide edges. This is the case, for example, in CdI₂(pyrazine), in which the cadmium cations are linked by pairs of μ-1,1 bridging halide anions into chains that are further connected into layers by the pyrazine ligands [CSD refcodes RINSOW, (Bailey & Pennington, 1997 ▸) and RINSOW01 (Pickardt & Staub, 1997 ▸)]. Starting from these results, we prepared the corresponding compounds with cadmium bromide and obtained a compound with the composition CdBr₂(C₆H₈N₂)(H₂O)·C₆H₈N₂·0.5H₂O that consists of octa­hedrally coordinated cadmium cations that are linked into chains via pairs of bromide anions (Näther, 2026b ▸). In further work, CdBr₂(C₆H₈N₂) was structurally characterized. This compound exhibits the same ratio between the cadmium halide and the coligand as CdI₂(C₆H₈N₂) (Näther, 2026c ▸). In contrast to the latter compound, where the cadmium cations adopt a tetra­hedral coordination, for the bromide compound an octa­hedral coordination with a chain structure was observed. To complete these investigations, we became inter­ested in the corresponding compounds with CdCl₂ and obtained crystals of the title compound, CdCl₂(C₆H₈N₂)₂·H₂O (I), which were characterized by single-crystal X-ray diffraction.

2. Structural commentary

The asymmetric unit of (I) is built up of two crystallographically independent cadmium cations that are both located on crystallographic twofold rotation axes, two crystallographically independent chloride anions and two distinct 2,3-di­methyl­pyrazine ligands as well as one water mol­ecule, all of them located in general positions. The cadmium cations are surrounded by four chloride anions and two terminally bonded 2,3-di­methyl­pyrazine ligands (Fig. 1 ▸). The bond angles show small deviations from the ideal octa­hedral values and there are no significant structural differences between the two crystallographically independent Cd centers (Table 1 ▸). The cadmium cations are linked by pairs of μ-1,1 bridging chloride anions into linear chains that propagate in the b-axis direction (Fig. 2 ▸).

Figure 1.

Crystal structure of (I) with labeling and displacement ellipsoids drawn at the 50% probability level. Symmetry codes: (i) −x + 1, y + 1, −z + ; (ii) x, y + 1, z; (iii) −x + 1, y, −z + .

Table 1. Selected geometric parameters (Å, °).

Cd1—N1	2.493 (3)	Cd2—N11	2.491 (3)
Cd1—Cl1	2.5773 (9)	Cd2—Cl2	2.5815 (9)
Cd1—Cl2i	2.5958 (9)	Cd2—Cl1	2.5930 (9)
Cd1—Cl2ii	2.5958 (9)
N1—Cd1—N1iii	176.45 (11)	N11—Cd2—Cl2	88.11 (7)
N1—Cd1—Cl1iii	95.65 (7)	N11iii—Cd2—Cl2	94.93 (7)
N1—Cd1—Cl1	86.91 (7)	Cl2—Cd2—Cl2iii	88.64 (4)
Cl1iii—Cd1—Cl1	88.14 (4)	N11—Cd2—Cl1	89.88 (7)
N1—Cd1—Cl2i	86.33 (7)	N11iii—Cd2—Cl1	87.06 (7)
N1iii—Cd1—Cl2i	91.11 (7)	Cl2—Cd2—Cl1	177.93 (2)
Cl1iii—Cd1—Cl2i	178.02 (2)	Cl2iii—Cd2—Cl1	91.98 (3)
Cl1—Cd1—Cl2i	91.95 (3)	Cl2iii—Cd2—Cl1iii	177.93 (2)
Cl1—Cd1—Cl2ii	178.02 (2)	Cl1—Cd2—Cl1iii	87.47 (4)
Cl2i—Cd1—Cl2ii	88.03 (4)	Cd1—Cl1—Cd2	92.20 (3)
N11—Cd2—N11iii	175.76 (11)	Cd2—Cl2—Cd1iv	91.66 (3)

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) .

Figure 2.

View of a part of a chain in the extended structure of (I).

This structure is therefore similar to that of CdBr₂(C₆H₈N₂), in which linear CdX chains are also found (Näther, 2026c ▸). The major difference is that the 2,3-di­methyl­pyrazine ligands are only terminally bonded in the title compound, whereas they act as bridging ligands in the bromide compound and this is also reflected in the different ratio between CdX₂ and the 2,3-di­methyl­pyrazine coligand, which is 1:2 in the title compound and 1:1 in the bromide compound. Moreover, these findings also show that in cadmium halide coordination compounds with 2,3-di­methyl­pyrazine, chloride and bromide anions behave in a similar way with an octa­hedral Cd coordination and the presence of chains, whereas for the corresponding iodide compounds a tetra­hedral coordination is observed (Näther, 2026a ▸). At first glance one would assume that the reason why the iodide compound shows a tetra­hedral coordination might originate from steric repulsion between the larger iodide anions, which is lower in a tetra­hedral coordination, but this would not explain why in CdI₂(pyrazine) an octa­hedral coordination is observed. One may therefore suggest that repulsion between the large iodide anions and the methyl group that is adjacent to the coordinating N atom is responsible for all these findings.

3. Supra­molecular features

In the extended structure of (I), the chains are linked via the water mol­ecules of crystallization into layers by O—H⋯N hydrogen bonds to the second N atom of the 2,3-di­methyl­pyrazine ligand that is not involved in the metal coordination (Fig. 3 ▸). These layers lie parallel to the ab plane (Fig. 3 ▸). The O—H⋯N bond angles are close to linear, indicating that this is a relatively strong inter­action (Table 2 ▸). There are also a number of C—H⋯Cl contacts, but most of them exhibit long distances and angles far from 180°, indicating only very weak inter­actions (Table 2 ▸). However, two of these contacts are relatively short with angles of 154 and 160°, indicating intra­chain hydrogen bonding (Table 2 ▸).

Figure 3.

Crystal structure of (I) in a view along the crystallographic a-axis direction.

Table 2. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1A⋯N12v	1.00 (7)	2.00 (7)	2.965 (4)	164 (5)
O1—H1B⋯N2	0.94 (6)	2.02 (7)	2.939 (5)	165 (5)
C3—H3⋯O1vi	0.95	2.61	3.282 (5)	128
C4—H4⋯Cl1	0.95	2.93	3.490 (4)	119
C4—H4⋯Cl2i	0.95	2.97	3.420 (4)	110
C5—H5B⋯Cl1vii	0.98	2.88	3.747 (3)	147
C5—H5C⋯Cl1iii	0.98	2.71	3.650 (4)	160
C5—H5C⋯Cl2ii	0.98	2.97	3.451 (4)	112
C13—H13⋯Cl1vii	0.95	2.98	3.786 (4)	143
C14—H14⋯Cl1iii	0.95	2.95	3.419 (4)	112
C14—H14⋯Cl2	0.95	2.94	3.510 (4)	120
C15—H15A⋯Cl1	0.98	2.90	3.470 (4)	118
C15—H15A⋯Cl2iii	0.98	2.76	3.670 (4)	154

Symmetry codes: (i) ; (ii) ; (iii) ; (v) ; (vi) ; (vii) .

4. Additional characterization

The purity of the title compound was investigated by powder X-ray diffraction (PXRD) and comparison of the experimental PXRD pattern with that calculated from the results of the single crystal structure determination indicate that a pure phase has been obtained. However, some reflections are slightly shifted to higher Bragg angles in the calculated pattern, because of the different temperature and the pattern shows unusually strong preferred orientation (Fig. 4 ▸).

Figure 4.

Experimental (top) and calculated powder patterns (bottom) for (I).

The thermal behavior of the title compound was investigated by thermogravimetry (TG) coupled to differential thermal analysis (DTA) to check if 2,3-di­methyl­pyrazine-deficient phases can be detected, as is frequently observed in such compounds. Upon heating three mass losses are observed, which are accompanied by endothermic events in the DTA curve (Fig. 5 ▸). The experimental mass loss in the first step of 4.23% is in very good agreement with that calculated for the removal of the water mol­ecules (4.31%) and the mass loss in the second step corresponds to the removal of 1.5 of the 2,3-di­methyl­pyrazine mol­ecules (Δm_calc. = 38.8%). Based on these results, one can expect that in the first step, a compound with the composition CdCl₂(C₆H₈N₂)₂ is formed, which transforms into (CdCl₂)₂(C₆H₈N₂) upon further heating.

Figure 5.

DTG, TG and DTA curves for (I).

The residues obtained after the first and second mass losses were investigated by PXRD. Comparison of the pattern of the residue with that of the pristine compound shows only very minor differences in the intensity and practically no shift in the reflection positions (Fig. S1). Two such experiments were performed with identical results. At first glance one would assume that this reaction might be topotactic, but at least some shift in peak positions would be expected. It is very unlikely that the title compound immediately decomposes on storage and that the anhydrate was measured because several TG-DTA experiments were performed using the same batch and in all of them the mass loss associated with removal of the water mol­ecules remain constant. On the other hand, we cannot exclude the possibility that the anhydrate is extremely hygroscopic and immediately transforms back to the title compound. The powder pattern of the residue obtained after the second mass loss is completely different from that of the title compound and shows that a powder of low crystallinity has formed (Fig. S2). The composition assumed for this residue seems to be a bit unusual and points to a more condensed CdCl₂ substructure. In this context it is noted that, for the corresponding copper(I) chloride–2,3-di­methyl­pyrazine coordination compounds, a number of different compounds with varying ratios between CuCl and 2,3-di­methyl­pyrazine have been reported. These include (CuCl)₄(C₆H₈N₂)₉ with a ratio of 4:9, CuCl(C₆H₈N₂) with a ratio of 1:1, (CuCl)₃(C₆H₈N₂)₂ with a ratio of 3:2 and (CuCl)₂(C₆H₈N₂) with a ratio of 2:1 (Jess & Näther, 2006 ▸).

5. Database survey

As mentioned above, several compounds with cadmium halides and 2,3-di­methyl­pyrazine have already been reported and this formed the basis for this work. This includes the iodide compounds CdI₂(C₆H₈N₂)₂ and CdI₂(C₆H₈N₂) (Näther, 2026a ▸), as well as the bromide compounds CdBr₂(C₆H₈N₂)(H₂O)·C₆H₈N₂·0.5H₂O and CdBr₂(C₆H₈N₂) (Näther, 2026b ▸,c ▸).

A search in the CSD (Version 5.43, 2025; Groom et al., 2016 ▸) using CONQUEST (Bruno et al., 2002 ▸) revealed that in several other compounds with pyrazine or pyridine and its derivatives, similar CdCl₂ chains and an octa­hedral coordination is found. This is the case, for example, in CdCl₂(pyridine)₂, which shows the same chain structure as the title compound but contains no water of crystallization [CSD refcodes CDPYCL01 (Paulus, 1969 ▸), CDPYCL03 (Satoh et al., 2001 ▸) and CDPYCL04 (Hu et al., 2003 ▸)]. The same structure is also found in CdCl₂(4-methyl­pyridine)₂ (BASQUI; Satoh et al., 2001 ▸), CdCl₂(3-methyl­pyridine)₂ [BASQOC (Satoh et al., 2001 ▸), BASQOC01 (Hu et al., 2003 ▸)]. CdCl₂(pyrazine) [TISSUJ (Pickardt & Staub, 1996 ▸), TISSUJ01 (Bailey & Pennington, 1997 ▸)] is an additional example but in contrast to the pyridine compounds, the CdCl₂ chains are linked into layers.

6. Synthesis, crystallization and experimental details

Cadmium chloride and 2,3-di­methyl­pyrazine were purchased from Sigma-Aldrich. To prepare (I), 1.00 mmol (183.3 mg) of CdCl₂ and 1.00 mmol (108.2 mg) of 2,3-di­methyl­pyrazine were reacted in 2 ml of water for 3 d at room temperature, which led to the formation of crystals suitable for single-crystal structure analysis.

The PXRD measurements were performed with Cu Kα₁ radiation (λ = 1.540598 Å) using a Stoe Transmission Powder Diffraction System (STADI P) equipped with a MYTHEN 1K detector and a Johansson-type Ge(111) monochromator.

Thermogravimetry and differential thermal analysis (TG-DTA) measurements were performed in a dynamic air atmosphere in Al₂O₃ crucibles using a STA-PT 1000 thermobalance from Linseis. The instrument was calibrated using standard reference materials.

7. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 3 ▸. The C—H hydrogen atoms were positioned with idealized geometry (methyl H atoms allowed to rotate but not to tip) and were refined isotropically with U_iso(H) = 1.2U_eq(C) (1.5 for methyl H atoms). The O-bound H atoms were located in difference maps and refined isotropically without restraints.

Table 3. Experimental details.

Crystal data
Chemical formula	[CdCl2(C6H8N2)2]·H2O
M r	417.60
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	170
a, b, c (Å)	30.6316 (15), 7.4391 (3), 16.3857 (8)
β (°)	121.538 (3)
V (Å3)	3182.3 (3)
Z	8
Radiation type	Mo Kα
μ (mm−1)	1.71
Crystal size (mm)	0.14 × 0.12 × 0.09
Data collection
Diffractometer	IPDS2
Absorption correction	Numerical (X-RED and X-SHAPE; Stoe, 2002 ▸)
Tmin, Tmax	0.719, 0.812
No. of measured, independent and observed [I > 2σ(I)] reflections	24424, 3836, 2792
R int	0.111
(sin θ/λ)max (Å−1)	0.661
Refinement
R[F2 > 2σ(F2)], wR(F2), S	0.047, 0.143, 1.03
No. of reflections	3836
No. of parameters	195
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)	1.03, −1.76

Computer programs: X-AREA (Stoe, 2002 ▸), SHELXT2014/4 (Sheldrick, 2015a ▸), SHELXL2016/6 (Sheldrick, 2015b ▸), DIAMOND (Brandenburg, 1999 ▸), XP in SHELXTL-PC (Sheldrick, 2008 ▸) and publCIF (Westrip, 2010 ▸).

Supplementary Material

CCDC reference: 2590645

Additional supporting information: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

catena-Poly[[[bis(2,3-dimethylpyrazine-κN¹)cadmium(II)]-di-µ-chlorido] monohydrate] . Crystal data

[CdCl2(C6H8N2)2]·H2O	F(000) = 1664
Mr = 417.60	Dx = 1.743 Mg m−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
a = 30.6316 (15) Å	Cell parameters from 22970 reflections
b = 7.4391 (3) Å	θ = 1.5–28.9°
c = 16.3857 (8) Å	µ = 1.71 mm−1
β = 121.538 (3)°	T = 170 K
V = 3182.3 (3) Å3	Block, colorless
Z = 8	0.14 × 0.12 × 0.09 mm

catena-Poly[[[bis(2,3-dimethylpyrazine-κN¹)cadmium(II)]-di-µ-chlorido] monohydrate] . Data collection

IPDS-2 diffractometer	2792 reflections with I > 2σ(I)
ω scans	Rint = 0.111
Absorption correction: numerical (X-Red and X-Shape; Stoe, 2002)	θmax = 28.0°, θmin = 1.6°
Tmin = 0.719, Tmax = 0.812	h = −40→40
24424 measured reflections	k = −8→9
3836 independent reflections	l = −21→21

catena-Poly[[[bis(2,3-dimethylpyrazine-κN¹)cadmium(II)]-di-µ-chlorido] monohydrate] . Refinement

Refinement on F2	Hydrogen site location: mixed
Least-squares matrix: full	H atoms treated by a mixture of independent and constrained refinement
R[F2 > 2σ(F2)] = 0.047	w = 1/[σ2(Fo2) + (0.0824P)2] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.143	(Δ/σ)max = 0.001
S = 1.03	Δρmax = 1.03 e Å−3
3836 reflections	Δρmin = −1.76 e Å−3
195 parameters	Extinction correction: SHELXL2016/6 (Sheldrick, 2015b), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 restraints	Extinction coefficient: 0.00097 (15)

catena-Poly[[[bis(2,3-dimethylpyrazine-κN¹)cadmium(II)]-di-µ-chlorido] monohydrate] . Special details

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

catena-Poly[[[bis(2,3-dimethylpyrazine-κN¹)cadmium(II)]-di-µ-chlorido] monohydrate] . Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Cd1	0.500000	0.73731 (5)	0.250000	0.03384 (15)
Cd2	0.500000	0.23652 (5)	0.250000	0.03428 (15)
Cl1	0.53794 (4)	0.48838 (10)	0.19592 (7)	0.0374 (2)
Cl2	0.46474 (4)	−0.01175 (10)	0.31017 (7)	0.0374 (2)
N1	0.58483 (13)	0.7477 (3)	0.4026 (2)	0.0375 (7)
C1	0.59557 (14)	0.7695 (4)	0.4922 (2)	0.0373 (7)
C2	0.64592 (14)	0.8044 (6)	0.5672 (2)	0.0467 (8)
N2	0.68450 (12)	0.8149 (5)	0.5519 (2)	0.0536 (8)
C3	0.67300 (14)	0.7877 (5)	0.4618 (3)	0.0469 (8)
H3	0.699816	0.790312	0.448839	0.056*
C4	0.62419 (15)	0.7566 (4)	0.3882 (3)	0.0413 (8)
H4	0.617810	0.740743	0.325322	0.050*
C5	0.55300 (15)	0.7540 (4)	0.5117 (3)	0.0417 (9)
H5A	0.545233	0.873110	0.526423	0.063*
H5B	0.563519	0.673542	0.566231	0.063*
H5C	0.522444	0.705258	0.455015	0.063*
C6	0.65882 (17)	0.8313 (7)	0.6686 (3)	0.0669 (12)
H6A	0.660295	0.714319	0.697424	0.100*
H6B	0.632439	0.905913	0.668492	0.100*
H6C	0.692140	0.891136	0.705752	0.100*
N11	0.57755 (12)	0.2489 (3)	0.4142 (2)	0.0368 (7)
C11	0.62713 (14)	0.2707 (4)	0.4435 (2)	0.0384 (8)
C12	0.66333 (13)	0.3077 (6)	0.5407 (2)	0.0449 (8)
N12	0.65036 (12)	0.3168 (5)	0.6062 (2)	0.0503 (7)
C13	0.60089 (15)	0.2888 (5)	0.5756 (2)	0.0470 (8)
H13	0.590506	0.289731	0.620968	0.056*
C14	0.56478 (16)	0.2589 (5)	0.4813 (3)	0.0431 (9)
H14	0.529946	0.244861	0.462766	0.052*
C15	0.64336 (14)	0.2545 (4)	0.3723 (3)	0.0423 (8)
H15A	0.614010	0.217636	0.310243	0.064*
H15B	0.670571	0.164260	0.394365	0.064*
H15C	0.656145	0.370793	0.365481	0.064*
C16	0.71882 (14)	0.3366 (7)	0.5745 (3)	0.0619 (11)
H16A	0.734999	0.408587	0.633216	0.093*
H16B	0.721521	0.399934	0.524842	0.093*
H16C	0.736137	0.220025	0.587352	0.093*
O1	0.79443 (13)	0.8800 (6)	0.6842 (2)	0.0899 (13)
H1A	0.806 (2)	0.853 (9)	0.752 (5)	0.12 (2)*
H1B	0.759 (2)	0.864 (8)	0.651 (4)	0.108 (19)*

catena-Poly[[[bis(2,3-dimethylpyrazine-κN¹)cadmium(II)]-di-µ-chlorido] monohydrate] . Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Cd1	0.0430 (2)	0.0296 (2)	0.0362 (2)	0.000	0.02573 (18)	0.000
Cd2	0.0436 (3)	0.0299 (2)	0.0362 (2)	0.000	0.02563 (19)	0.000
Cl1	0.0490 (5)	0.0325 (5)	0.0419 (5)	−0.0010 (3)	0.0315 (4)	−0.0015 (3)
Cl2	0.0484 (5)	0.0323 (5)	0.0417 (5)	−0.0006 (3)	0.0307 (4)	−0.0013 (3)
N1	0.0498 (18)	0.0335 (17)	0.0373 (16)	0.0001 (11)	0.0284 (14)	−0.0009 (10)
C1	0.0463 (19)	0.0342 (19)	0.0381 (17)	0.0016 (13)	0.0267 (16)	0.0032 (12)
C2	0.053 (2)	0.053 (2)	0.0357 (16)	0.0010 (17)	0.0245 (15)	0.0019 (16)
N2	0.0452 (16)	0.072 (2)	0.0395 (15)	−0.0004 (17)	0.0194 (13)	0.0003 (16)
C3	0.0452 (19)	0.054 (2)	0.0474 (19)	0.0022 (16)	0.0285 (17)	0.0023 (16)
C4	0.049 (2)	0.044 (2)	0.0389 (18)	0.0022 (13)	0.0281 (17)	0.0020 (13)
C5	0.055 (2)	0.046 (2)	0.0363 (17)	0.0021 (14)	0.0320 (17)	0.0028 (12)
C6	0.066 (3)	0.094 (4)	0.0358 (18)	−0.001 (2)	0.0232 (18)	−0.005 (2)
N11	0.0425 (16)	0.0355 (18)	0.0387 (16)	0.0018 (10)	0.0257 (14)	0.0027 (10)
C11	0.0457 (19)	0.0344 (19)	0.0364 (17)	0.0019 (13)	0.0225 (15)	0.0010 (12)
C12	0.0425 (18)	0.050 (2)	0.0426 (17)	0.0039 (16)	0.0223 (15)	0.0005 (16)
N12	0.0491 (16)	0.062 (2)	0.0381 (15)	0.0037 (15)	0.0213 (13)	−0.0010 (15)
C13	0.054 (2)	0.055 (2)	0.0370 (17)	0.0032 (17)	0.0274 (16)	−0.0001 (15)
C14	0.048 (2)	0.045 (2)	0.044 (2)	0.0037 (14)	0.0300 (18)	0.0020 (13)
C15	0.0422 (19)	0.045 (2)	0.048 (2)	0.0013 (13)	0.0294 (18)	0.0007 (13)
C16	0.045 (2)	0.086 (3)	0.049 (2)	0.000 (2)	0.0210 (17)	−0.005 (2)
O1	0.0568 (19)	0.168 (4)	0.0464 (16)	−0.017 (2)	0.0282 (15)	0.002 (2)

catena-Poly[[[bis(2,3-dimethylpyrazine-κN¹)cadmium(II)]-di-µ-chlorido] monohydrate] . Geometric parameters (Å, º)

Cd1—N1	2.493 (3)	C5—H5B	0.9800
Cd1—N1i	2.493 (3)	C5—H5C	0.9800
Cd1—Cl1i	2.5773 (9)	C6—H6A	0.9800
Cd1—Cl1	2.5773 (9)	C6—H6B	0.9800
Cd1—Cl2ii	2.5958 (9)	C6—H6C	0.9800
Cd1—Cl2iii	2.5958 (9)	N11—C11	1.342 (5)
Cd2—N11	2.491 (3)	N11—C14	1.348 (5)
Cd2—N11i	2.491 (3)	C11—C12	1.412 (5)
Cd2—Cl2	2.5815 (9)	C11—C15	1.494 (5)
Cd2—Cl2i	2.5815 (9)	C12—N12	1.328 (4)
Cd2—Cl1	2.5930 (9)	C12—C16	1.503 (5)
Cd2—Cl1i	2.5930 (9)	N12—C13	1.340 (5)
N1—C1	1.337 (4)	C13—C14	1.367 (5)
N1—C4	1.346 (5)	C13—H13	0.9500
C1—C2	1.404 (5)	C14—H14	0.9500
C1—C5	1.500 (5)	C15—H15A	0.9800
C2—N2	1.332 (5)	C15—H15B	0.9800
C2—C6	1.506 (4)	C15—H15C	0.9800
N2—C3	1.342 (5)	C16—H16A	0.9800
C3—C4	1.363 (5)	C16—H16B	0.9800
C3—H3	0.9500	C16—H16C	0.9800
C4—H4	0.9500	O1—H1A	1.00 (7)
C5—H5A	0.9800	O1—H1B	0.94 (6)
N1—Cd1—N1i	176.45 (11)	N1—C4—C3	121.5 (3)
N1—Cd1—Cl1i	95.65 (7)	N1—C4—H4	119.3
N1i—Cd1—Cl1i	86.91 (7)	C3—C4—H4	119.3
N1—Cd1—Cl1	86.91 (7)	C1—C5—H5A	109.5
N1i—Cd1—Cl1	95.65 (7)	C1—C5—H5B	109.5
Cl1i—Cd1—Cl1	88.14 (4)	H5A—C5—H5B	109.5
N1—Cd1—Cl2ii	86.33 (7)	C1—C5—H5C	109.5
N1i—Cd1—Cl2ii	91.11 (7)	H5A—C5—H5C	109.5
Cl1i—Cd1—Cl2ii	178.02 (2)	H5B—C5—H5C	109.5
Cl1—Cd1—Cl2ii	91.95 (3)	C2—C6—H6A	109.5
N1—Cd1—Cl2iii	91.11 (7)	C2—C6—H6B	109.5
N1i—Cd1—Cl2iii	86.33 (7)	H6A—C6—H6B	109.5
Cl1i—Cd1—Cl2iii	91.95 (3)	C2—C6—H6C	109.5
Cl1—Cd1—Cl2iii	178.02 (2)	H6A—C6—H6C	109.5
Cl2ii—Cd1—Cl2iii	88.03 (4)	H6B—C6—H6C	109.5
N11—Cd2—N11i	175.76 (11)	C11—N11—C14	117.3 (3)
N11—Cd2—Cl2	88.11 (7)	C11—N11—Cd2	130.7 (2)
N11i—Cd2—Cl2	94.93 (7)	C14—N11—Cd2	111.3 (3)
N11—Cd2—Cl2i	94.93 (7)	N11—C11—C12	120.1 (3)
N11i—Cd2—Cl2i	88.11 (7)	N11—C11—C15	119.2 (3)
Cl2—Cd2—Cl2i	88.64 (4)	C12—C11—C15	120.7 (3)
N11—Cd2—Cl1	89.88 (7)	N12—C12—C11	122.1 (3)
N11i—Cd2—Cl1	87.06 (7)	N12—C12—C16	117.0 (3)
Cl2—Cd2—Cl1	177.93 (2)	C11—C12—C16	120.9 (3)
Cl2i—Cd2—Cl1	91.98 (3)	C12—N12—C13	116.5 (3)
N11—Cd2—Cl1i	87.06 (7)	N12—C13—C14	122.5 (3)
N11i—Cd2—Cl1i	89.87 (7)	N12—C13—H13	118.8
Cl2—Cd2—Cl1i	91.98 (3)	C14—C13—H13	118.8
Cl2i—Cd2—Cl1i	177.93 (2)	N11—C14—C13	121.4 (4)
Cl1—Cd2—Cl1i	87.47 (4)	N11—C14—H14	119.3
Cd1—Cl1—Cd2	92.20 (3)	C13—C14—H14	119.3
Cd2—Cl2—Cd1iv	91.66 (3)	C11—C15—H15A	109.5
C1—N1—C4	117.3 (3)	C11—C15—H15B	109.5
C1—N1—Cd1	129.4 (3)	H15A—C15—H15B	109.5
C4—N1—Cd1	112.7 (2)	C11—C15—H15C	109.5
N1—C1—C2	120.6 (3)	H15A—C15—H15C	109.5
N1—C1—C5	118.8 (3)	H15B—C15—H15C	109.5
C2—C1—C5	120.5 (3)	C12—C16—H16A	109.5
N2—C2—C1	121.5 (3)	C12—C16—H16B	109.5
N2—C2—C6	116.9 (3)	H16A—C16—H16B	109.5
C1—C2—C6	121.6 (3)	C12—C16—H16C	109.5
C2—N2—C3	116.7 (3)	H16A—C16—H16C	109.5
N2—C3—C4	122.3 (3)	H16B—C16—H16C	109.5
N2—C3—H3	118.8	H1A—O1—H1B	104 (4)
C4—C3—H3	118.8
C4—N1—C1—C2	1.4 (5)	C14—N11—C11—C12	−1.8 (5)
Cd1—N1—C1—C2	−168.3 (3)	Cd2—N11—C11—C12	167.8 (2)
C4—N1—C1—C5	−177.9 (3)	C14—N11—C11—C15	177.9 (3)
Cd1—N1—C1—C5	12.4 (4)	Cd2—N11—C11—C15	−12.5 (4)
N1—C1—C2—N2	−0.7 (6)	N11—C11—C12—N12	2.0 (6)
C5—C1—C2—N2	178.5 (4)	C15—C11—C12—N12	−177.6 (4)
N1—C1—C2—C6	179.4 (4)	N11—C11—C12—C16	−178.6 (4)
C5—C1—C2—C6	−1.3 (6)	C15—C11—C12—C16	1.7 (6)
C1—C2—N2—C3	−1.0 (6)	C11—C12—N12—C13	0.1 (6)
C6—C2—N2—C3	178.9 (4)	C16—C12—N12—C13	−179.2 (4)
C2—N2—C3—C4	2.1 (6)	C12—N12—C13—C14	−2.4 (6)
C1—N1—C4—C3	−0.4 (5)	C11—N11—C14—C13	−0.4 (5)
Cd1—N1—C4—C3	171.0 (3)	Cd2—N11—C14—C13	−172.0 (3)
N2—C3—C4—N1	−1.4 (6)	N12—C13—C14—N11	2.7 (6)

Symmetry codes: (i) −x+1, y, −z+1/2; (ii) −x+1, y+1, −z+1/2; (iii) x, y+1, z; (iv) x, y−1, z.

catena-Poly[[[bis(2,3-dimethylpyrazine-κN¹)cadmium(II)]-di-µ-chlorido] monohydrate] . Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1A···N12v	1.00 (7)	2.00 (7)	2.965 (4)	164 (5)
O1—H1B···N2	0.94 (6)	2.02 (7)	2.939 (5)	165 (5)
C3—H3···O1vi	0.95	2.61	3.282 (5)	128
C4—H4···Cl1	0.95	2.93	3.490 (4)	119
C4—H4···Cl2ii	0.95	2.97	3.420 (4)	110
C5—H5B···Cl1vii	0.98	2.88	3.747 (3)	147
C5—H5C···Cl1i	0.98	2.71	3.650 (4)	160
C5—H5C···Cl2iii	0.98	2.97	3.451 (4)	112
C13—H13···Cl1vii	0.95	2.98	3.786 (4)	143
C14—H14···Cl1i	0.95	2.95	3.419 (4)	112
C14—H14···Cl2	0.95	2.94	3.510 (4)	120
C15—H15A···Cl1	0.98	2.90	3.470 (4)	118
C15—H15A···Cl2i	0.98	2.76	3.670 (4)	154

Symmetry codes: (i) −x+1, y, −z+1/2; (ii) −x+1, y+1, −z+1/2; (iii) x, y+1, z; (v) −x+3/2, y+1/2, −z+3/2; (vi) −x+3/2, −y+3/2, −z+1; (vii) x, −y+1, z+1/2.