(Acetato-κO)aqua­(1H-imidazole-κN³)(picolinato-κ²N,O)copper(II) 0.87-hy­drate: a Z′ > 1 structure

The crystal structure of the title compound, [Cu(C₆H₄NO₂)(C₂H₃O₂)(C₃H₄N₂)(H₂O)]·0.87H₂O, has a square-pyramidal-coordinated Cu^II centre (the imidazole is trans to the picolinate N atom, the acetate is trans to the picolinate –CO₂ group and the aqua ligand is in a Jahn–Teller-elongated apical position) and has two symmetry-independent mol­ecules in the unit cell (Z′ = 2), which are connected through complementary imidazole–picolinate N—H...O hydrogen bonding. The two partially occupied solvent water mol­ecules are each disordered over two positions. The disordered solvent water mol­ecules, together with pseudo­symmetry elements, support the notion that a crystal structure with multiple identical chemical formula units in the structural asymmetric unit (Z′ > 1) can represent a crystal `on the way', that is, a kinetic intermediate form which has not yet reached its thermodynamic minimum. Neighbouring mol­ecules form π–π stacks between their imidazole and picolinate N-hetero­cycles, with centroid–centroid distances in the range 3.582 (2)–3.764 (2) Å.

S1. Comment

The asymmetric unit of the title complex, (I), has two identical chemical formula units (Z' = 2), i.e. two symmetry-independent molecules including the partially occupied and disordered solvent water (Fig. 1a). The two independent molecules have similar structural data, hence there is no immediately apparent significant conformational difference (Fig. 1b). The Cu atom is in a square-pyramidal environment with trans N and trans O donor atoms, respectively, and long apical Cu—OH₂ bonds due to the Jahn–Teller effect.

Bond lengths and angles in (I) are as expected. The crystal packing is governed by O—H···O and N—H···O hydrogen bonding (Table 1, Fig. 2), the geometric parameters of which are within the normal range (Habib & Janiak, 2008; Wisser & Janiak, 2007a,b). Complementary N—H···O bonds are formed between the two symmetry-independent complex molecules from their imidazole N—H to the uncoordinated picolinate carboxylate O atom (Fig. 1a). The aqua ligand forms hydrogen bonds to both uncoordinated carboxylate O atoms of the picolinate and acetate ligands (Fig. 2). Together, these hydrogen bonds give a two-dimensional hydrogen-bonded double layer parallel to the ab plane (Fig. 2). Furthermore, the partially occupied solvent water atoms O6A and O26A form hydrogen bonds between acetate atoms O1 and O2, and O21 and O22, respectively, of two adjacent molecules along b (not shown, H atoms could not be found). π–π interactions between the picolinate and imidazole rings add to the supramolecular two-dimensional double layer parallel to the ab plane (Fig. 3). The π–π stacking interactions can be viewed as strong because of the rather short centroid-to-centroid contacts (3.582–3.764 Å), small slip angles (23–28°) and short interplanar separations (3.1–3.4 Å), which translate into a sizeable overlap of the nearly parallel aromatic planes (interplanar angle 4.83 or 9.78°) (Janiak, 2000).

There is ongoing discussion of the origin of crystal structures with multiple identical molecules, i.e. formula units in the structural asymmetric unit or so-called Z' > 1 structures (Gavezotti, 2008; van Eijck & Kroon, 2000). These can be regarded as a `fossil relic' of a more stable form (Steed, 2003), as strong and special supramolecular interactions between the symmetry-independent units (Althoff et al., 2006; Babu & Nangia, 2007; Hao et al., 2005) or as a crystal `on the way' (Desiraju, 2007; Nichol & Clegg, 2007; Ruiz et al., 2008). The impossibility of packing chiral molecules in a centrosymmetric structure can also lead to the presence of two independent molecules (Anderson & Steed, 2007). A Z' > 1 structure is also obtained when the molecule has different quasi-energetic conformations, with these conformations co-existing in the crystal structure (Hosseini Monfared et al., 2009; Roy et al., 2006).

Two X-ray data sets were collected on two crystals of the title compound from two different batches to ascertain the Z' = 2 phenomenon. One crystal was structurally investigated after drying and the other was taken directly from the mother liquor. Both data sets refined to the identical Z' = 2 structure, including the same disordered and partially occupied solvent water molecules. The complementary N—H···O hydrogen-bonding interaction between the molecules containing atoms Cu1 and Cu2 may be viewed as a special supramolecular interaction which creates a `dimer' and thereby gives a Z' = 2 structure. However, the two independent molecules are superficially related by a pseudo C<sub>2</sub> axis at (1/2, y, 1/4) (Fig. 1a) or a pseudo n-glide plane at (0, 1/2, 0), thus leading to a possible refinement in C2/c (see Supplementary material, _refine_special_details section). The only atoms with no symmetry-related counterpart are C8, C9, C28 and C29 from the aromatic ring of the picolinate group (Fig. 1a). It is here where the two molecules deviate most in their overlay and where a tilt disorder occurs upon refinement in C2/c. Then the Z' = 2 structure would be due to quasi-energetic conformations co-existing in the crystal. However, we view both the `dimer' and the slight conformational difference, and hence the Z' = 2 structure of (I), as consequences of partial crystal water loss, which apparently takes place when the compound is still in its mother liquor, thereby representing a `crystal on the way' (Desiraju, 2007; Ruiz et al., 2008).

S2. Experimental

A methanol solution (10 ml) of Cu(CH₃COO)₂.H₂O (0.40 g, 2.0 mmol) was mixed with a methanol solution (5 ml) of 2-picolinic acid (0.25 g, 2.0 mmol), followed by the addition of imidazole (0.14 g, 2.0 mmol) dissolved in methanol (5 ml). The resulting dark-blue solution was left to stand at room temperature. Dark-blue [Green in CIF tables - please check] single crystals suitable for X-ray diffraction were obtained by slow evaporation of the solvent after several days (yield 82%). Elemental analysis: C₁₁H_14.76CuN₃O_5.88 (346.55), calculated: C 38.11, H 4.29, N 12.12; found: C 38.31, H 3.55, N 12.29%. IR (KBr, ν, cm^-1): 3432 (OH), 3135 (NH), 2939 (CH), 1623 (CO and CC), 1387 (CH).

S3. Refinement

H atoms for aromatic CH and methyl CH₃ groups were positioned geometrically (C—H = 0.94 Å for aromatic and C—H = 0.97 Å for methyl H atoms) and refined using a riding model, with U_iso(H) = 1.2U_eq(CH) or 1.5U_eq(methyl C). H atoms on the aqua ligand and on the imidazole N atom were found and refined with U_iso(H) = 1.5U_eq(O,N). The O—H bond distance of one H atom on each aqua ligand had to be controlled through a DFIX restraint (SHELXL97; Sheldrick, 2008), with O—H = 0.90 (5) Å. [Sandy: The solvent water H atoms don't seem to have been included in the _sum formula]

Computing details

Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2009); software used to prepare material for publication: publCIF (Westrip, 2009).

Figures

	Fig. 1. (a). The asymmetric unit of (I), with the atom-numbering scheme, showing the two identical chemical formula units, i.e. the two symmetry-independent molecules with their complementary hydrogen bonds (dashed lines; details in Table 1) and the disordered solvent water O atoms. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as small spheres of arbitrary radii. Only positions O6A/O26A, O6A/O26B and O26A/O6B can be occupied simultaneously, but not O6A and O6B, O26A and O26B, or O6B and O26B. Occupation factors refined to about 0.63 (2) for the A and 0.24 (2) for the B positions, giving an occupancy of about 0.87 for each water molecule. (b) An overlay of the two symmetry-independent molecules in (I), by specifying Cu1/Cu2, acetate-O1/O21 and picolinate-N3/23 as pairs (r.m.s. deviation 0.00464 Å). Molecule 1 (black) is that with atom Cu1 and molecule 2 (grey) that with atom Cu2.
	Fig. 2. A packing diagram for (I), with the hydrogen-bonding interactions (dashed lines) as given in Table 1. C atoms are depicted in stick mode for clarity.
	Fig. 3. A packing diagram for (I) in wire-frame mode, with the π–π stacking interactions in the supramolecular double-layer parallel to the ab plane. Centroid-to-centroid contacts are indicated as thick dashed lines with their distances given. [Symmetry codes: (iv) 1 - x, 1/2 + y, 3/2 - z; (v) -x, 1/2 + y, 3/2 - z; (vi) 1 + x, y, z.]

(Acetato-κO)aqua(1H-imidazole-κN³)(picolinato- κ²N,O)copper(II) 0.87-hydrate

Crystal data

[Cu(C6H4NO2)(C2H3O2)(C3H4N2)(H2O)]·0.87H2O	F(000) = 1422
Mr = 346.44	Dx = 1.639 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 4430 reflections
a = 15.5708 (13) Å	θ = 2.8–25.0°
b = 6.5334 (5) Å	µ = 1.59 mm^−1
c = 29.437 (2) Å	T = 203 K
β = 110.333 (5)°	Isometric, blue
V = 2808.0 (4) Å^3	0.21 × 0.15 × 0.04 mm
Z = 8

Data collection

Bruker APEXII CCD area-detector diffractometer	5430 independent reflections
Radiation source: sealed tube	3948 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.049
ω scans	θmax = 25.9°, θmin = 1.4°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −19→19
Tmin = 0.731, Tmax = 0.941	k = −8→8
30383 measured reflections	l = −36→36

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)] = 0.035	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.096	H atoms treated by a mixture of independent and constrained refinement
S = 1.08	w = 1/[σ^2(Fo^2) + (0.0449P)^2 + 0.4344P] where P = (Fo^2 + 2Fc^2)/3
5430 reflections	(Δ/σ)max = 0.002
421 parameters	Δρmax = 0.36 e Å^−3
2 restraints	Δρmin = −0.46 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.

The crystal water molecules O6 and O26 are only partially occupied and disordered over two positions A and B, each. Occupation factors were refined individually to about 0.63 (2) for the A and 0.24 (2) for the B positions giving an occupancy of about 0.87 for each water molecule. This disorder leads to ALERT levels A and B because of apparent short O···O contacts, in particular a short O6B···O26B contact as ALERT level A. However, only the positions O6A - O26A, O6A - O26B and O26A - O6B can be occupied simultaneously, but not O6A and O6B, O26A and O26B and the noted O6B and O26B. Taking this disorder into account resolves the ALERT level A. ALERT level B concerns apparent short O···O contacts where no hydrogen bonds are present. H atoms of the disordered crystal water molecules were neither found nor refined and could not be calculated. Yet, the short inter O···O contacts are all within a hydrogen-bonding range.

Pseudo-symmetry elements were detected with ADDSYM by Chester CHECKCIF routines (ALERT level B) and by PLATON. Refinement could also be carried out in the space group C2/c. Yet, a large number of 4678 systematic absence violations including some stronger reflections were then noted. Also, a tilt disorder would then occur in the aromatic ring of the picolinato group.

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

	x	y	z	Uiso*/Ueq	Occ. (<1)
Cu1	0.01495 (2)	0.13836 (5)	0.641748 (10)	0.02639 (11)
O1	−0.04407 (13)	0.1499 (3)	0.57198 (7)	0.0363 (5)
O2	−0.05073 (16)	0.4855 (3)	0.57431 (8)	0.0578 (6)
C1	−0.1058 (3)	0.3207 (6)	0.49728 (12)	0.0691 (11)
H1A	−0.1317	0.4539	0.4856	0.104*
H1B	−0.1538	0.2180	0.4874	0.104*
H1C	−0.0589	0.2876	0.4838	0.104*
C2	−0.0639 (2)	0.3249 (5)	0.55212 (10)	0.0395 (7)
O3	0.02970 (15)	−0.2227 (3)	0.64563 (7)	0.0359 (5)
H3A	0.003 (2)	−0.299 (5)	0.6239 (12)	0.054*
H3B	0.022 (2)	−0.273 (5)	0.6670 (11)	0.054*
N1	0.13653 (15)	0.1873 (3)	0.63853 (8)	0.0280 (5)
N2	0.28613 (16)	0.2162 (4)	0.66223 (9)	0.0332 (6)
H2	0.339 (2)	0.225 (5)	0.6789 (11)	0.050*
C3	0.16382 (19)	0.1784 (4)	0.59854 (10)	0.0315 (6)
H3	0.1245	0.1626	0.5663	0.038*
C4	0.25605 (19)	0.1960 (4)	0.61322 (10)	0.0348 (6)
H4	0.2922	0.1946	0.5934	0.042*
C5	0.21322 (17)	0.2117 (4)	0.67618 (10)	0.0300 (6)
H5	0.2159	0.2242	0.7085	0.036*
N3	−0.10355 (14)	0.1332 (3)	0.65406 (8)	0.0276 (5)
C6	−0.18899 (18)	0.1295 (4)	0.62210 (10)	0.0318 (6)
H6	−0.1979	0.1352	0.5889	0.038*
C7	−0.26473 (18)	0.1176 (4)	0.63618 (11)	0.0338 (6)
H7	−0.3241	0.1181	0.6129	0.041*
C8	−0.25204 (19)	0.1050 (4)	0.68468 (10)	0.0363 (7)
H8	−0.3026	0.0952	0.6950	0.044*
C9	−0.16380 (18)	0.1069 (4)	0.71813 (10)	0.0324 (6)
H9	−0.1534	0.0972	0.7515	0.039*
C10	−0.09148 (17)	0.1234 (4)	0.70156 (9)	0.0269 (6)
C11	0.00731 (17)	0.1286 (4)	0.73458 (9)	0.0268 (6)
O4	0.06603 (12)	0.1380 (3)	0.71380 (6)	0.0304 (4)
O5	0.02501 (12)	0.1231 (3)	0.77895 (6)	0.0333 (4)
Cu2	0.47722 (2)	0.13803 (5)	0.861393 (10)	0.02570 (11)
O21	0.53677 (13)	0.1507 (3)	0.93119 (6)	0.0353 (5)
O22	0.5378 (2)	0.4847 (4)	0.92529 (8)	0.0727 (8)
C21	0.6055 (3)	0.3344 (6)	1.00374 (12)	0.0740 (12)
H21A	0.6358	0.4655	1.0129	0.111*
H21B	0.6506	0.2256	1.0132	0.111*
H21C	0.5614	0.3159	1.0199	0.111*
C22	0.5561 (2)	0.3282 (5)	0.94892 (11)	0.0443 (8)
O23	0.47744 (16)	−0.2188 (3)	0.85283 (8)	0.0406 (5)
H23A	0.501 (2)	−0.301 (6)	0.8730 (13)	0.061*
H23B	0.491 (2)	−0.261 (5)	0.8317 (11)	0.061*
N21	0.35402 (14)	0.1320 (3)	0.86523 (7)	0.0266 (5)
N22	0.20452 (15)	0.1181 (3)	0.84211 (9)	0.0313 (5)
H22	0.151 (2)	0.117 (4)	0.8255 (11)	0.047*
C23	0.32837 (19)	0.1359 (4)	0.90557 (10)	0.0306 (6)
H23	0.3687	0.1427	0.9378	0.037*
C24	0.23612 (19)	0.1283 (4)	0.89140 (10)	0.0322 (6)
H24	0.2007	0.1299	0.9116	0.039*
C25	0.27660 (18)	0.1209 (4)	0.82773 (10)	0.0302 (6)
H25	0.2730	0.1156	0.7952	0.036*
N23	0.59503 (14)	0.1762 (3)	0.84896 (8)	0.0267 (5)
C26	0.68096 (18)	0.1712 (4)	0.88060 (10)	0.0310 (6)
H26	0.6905	0.1466	0.9135	0.037*
C27	0.75568 (18)	0.2008 (4)	0.86681 (10)	0.0335 (6)
H27	0.8152	0.1958	0.8898	0.040*
C28	0.74218 (18)	0.2377 (4)	0.81882 (10)	0.0329 (6)
H28	0.7924	0.2594	0.8087	0.040*
C29	0.65364 (17)	0.2426 (4)	0.78565 (10)	0.0304 (6)
H29	0.6427	0.2678	0.7527	0.036*
C30	0.58178 (17)	0.2096 (4)	0.80209 (9)	0.0256 (6)
C31	0.48344 (17)	0.2066 (4)	0.76946 (9)	0.0273 (6)
O24	0.42492 (12)	0.1806 (3)	0.78998 (6)	0.0311 (4)
O25	0.46485 (12)	0.2296 (3)	0.72527 (6)	0.0342 (5)
O6A	−0.1358 (10)	−0.1813 (8)	0.5179 (2)	0.093 (4)	0.625 (18)
O6B	−0.2045 (18)	−0.131 (3)	0.5055 (6)	0.102 (8)	0.236 (18)
O26A	0.6386 (11)	−0.1825 (9)	0.9762 (2)	0.089 (4)	0.64 (2)
O26B	0.703 (2)	−0.136 (4)	0.9874 (7)	0.085 (7)	0.23 (2)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu1	0.02498 (19)	0.0327 (2)	0.01962 (18)	−0.00169 (13)	0.00546 (14)	0.00012 (13)
O1	0.0376 (11)	0.0452 (12)	0.0221 (10)	−0.0082 (9)	0.0052 (9)	0.0013 (9)
O2	0.0714 (16)	0.0472 (14)	0.0465 (13)	−0.0046 (12)	0.0101 (12)	−0.0057 (12)
C1	0.084 (3)	0.077 (3)	0.0309 (19)	−0.015 (2)	−0.0001 (19)	0.0092 (18)
C2	0.0341 (16)	0.051 (2)	0.0281 (16)	−0.0070 (14)	0.0043 (13)	0.0062 (14)
O3	0.0428 (12)	0.0351 (12)	0.0320 (12)	−0.0045 (9)	0.0158 (10)	−0.0006 (9)
N1	0.0301 (12)	0.0292 (12)	0.0238 (12)	−0.0009 (9)	0.0082 (10)	0.0018 (9)
N2	0.0240 (12)	0.0363 (13)	0.0378 (14)	−0.0009 (11)	0.0088 (11)	0.0038 (11)
C3	0.0361 (16)	0.0345 (16)	0.0243 (14)	−0.0025 (12)	0.0109 (12)	0.0012 (11)
C4	0.0371 (17)	0.0360 (15)	0.0351 (16)	−0.0025 (13)	0.0175 (14)	0.0013 (13)
C5	0.0302 (15)	0.0306 (14)	0.0287 (15)	−0.0021 (12)	0.0095 (12)	0.0021 (12)
N3	0.0277 (12)	0.0278 (12)	0.0246 (12)	0.0013 (9)	0.0057 (10)	0.0008 (9)
C6	0.0296 (15)	0.0318 (15)	0.0283 (15)	0.0012 (12)	0.0028 (12)	0.0002 (12)
C7	0.0248 (14)	0.0298 (15)	0.0411 (17)	0.0017 (11)	0.0042 (13)	−0.0029 (13)
C8	0.0285 (15)	0.0400 (17)	0.0415 (17)	0.0020 (12)	0.0133 (13)	−0.0048 (13)
C9	0.0303 (15)	0.0401 (17)	0.0288 (14)	0.0030 (12)	0.0128 (12)	−0.0052 (12)
C10	0.0295 (14)	0.0225 (13)	0.0276 (14)	0.0022 (11)	0.0085 (12)	−0.0021 (11)
C11	0.0273 (14)	0.0257 (14)	0.0266 (14)	0.0017 (11)	0.0082 (12)	−0.0036 (11)
O4	0.0246 (10)	0.0442 (11)	0.0219 (9)	−0.0002 (8)	0.0075 (8)	−0.0018 (8)
O5	0.0310 (10)	0.0481 (12)	0.0202 (10)	0.0012 (9)	0.0081 (8)	−0.0032 (8)
Cu2	0.02388 (19)	0.0333 (2)	0.01921 (18)	0.00230 (13)	0.00662 (14)	0.00069 (13)
O21	0.0347 (11)	0.0484 (13)	0.0213 (10)	0.0060 (9)	0.0076 (8)	0.0001 (9)
O22	0.123 (2)	0.0447 (15)	0.0449 (14)	0.0208 (15)	0.0223 (15)	0.0053 (12)
C21	0.092 (3)	0.077 (3)	0.0317 (19)	0.017 (2)	−0.004 (2)	−0.0132 (18)
C22	0.0447 (19)	0.052 (2)	0.0327 (17)	0.0127 (15)	0.0089 (15)	−0.0071 (15)
O23	0.0564 (14)	0.0368 (12)	0.0364 (12)	0.0089 (10)	0.0261 (11)	0.0012 (9)
N21	0.0278 (12)	0.0307 (12)	0.0225 (11)	0.0032 (9)	0.0103 (10)	0.0014 (9)
N22	0.0225 (12)	0.0345 (13)	0.0359 (14)	0.0004 (10)	0.0087 (11)	0.0013 (10)
C23	0.0371 (16)	0.0312 (15)	0.0259 (14)	0.0006 (12)	0.0142 (12)	0.0019 (11)
C24	0.0368 (16)	0.0320 (15)	0.0333 (15)	0.0012 (12)	0.0191 (13)	0.0034 (12)
C25	0.0306 (15)	0.0339 (15)	0.0282 (14)	0.0026 (12)	0.0128 (12)	0.0002 (12)
N23	0.0262 (12)	0.0298 (12)	0.0233 (12)	0.0008 (9)	0.0075 (10)	−0.0008 (9)
C26	0.0285 (15)	0.0351 (16)	0.0247 (14)	0.0016 (11)	0.0032 (12)	−0.0027 (11)
C27	0.0254 (15)	0.0325 (15)	0.0390 (17)	−0.0004 (12)	0.0065 (13)	−0.0051 (13)
C28	0.0287 (15)	0.0315 (16)	0.0421 (17)	−0.0008 (12)	0.0166 (13)	−0.0056 (13)
C29	0.0305 (15)	0.0315 (16)	0.0307 (15)	−0.0024 (11)	0.0125 (12)	−0.0034 (12)
C30	0.0258 (14)	0.0232 (13)	0.0277 (14)	−0.0014 (11)	0.0091 (11)	−0.0023 (11)
C31	0.0284 (14)	0.0250 (13)	0.0281 (15)	−0.0009 (11)	0.0095 (12)	0.0005 (11)
O24	0.0239 (10)	0.0484 (12)	0.0217 (10)	−0.0027 (8)	0.0087 (8)	0.0026 (8)
O25	0.0302 (10)	0.0526 (12)	0.0203 (10)	−0.0045 (9)	0.0095 (8)	0.0034 (9)
O6A	0.151 (10)	0.058 (3)	0.052 (3)	−0.016 (4)	0.012 (4)	−0.001 (2)
O6B	0.077 (15)	0.172 (18)	0.051 (9)	0.008 (12)	0.012 (9)	0.008 (9)
O26A	0.130 (11)	0.066 (3)	0.053 (3)	0.016 (4)	0.008 (4)	0.003 (2)
O26B	0.063 (15)	0.130 (14)	0.052 (9)	0.015 (11)	0.006 (9)	−0.001 (8)

Geometric parameters (Å, º)

Cu1—O1	1.9381 (18)	Cu2—O21	1.9401 (18)
Cu1—N1	1.954 (2)	Cu2—N21	1.961 (2)
Cu1—O4	1.9897 (18)	Cu2—O24	1.9923 (17)
Cu1—N3	2.000 (2)	Cu2—N23	2.007 (2)
Cu1—O3	2.369 (2)	Cu2—O23	2.345 (2)
O1—C2	1.272 (3)	O21—C22	1.265 (4)
O2—C2	1.215 (4)	O22—C22	1.213 (4)
C1—C2	1.517 (4)	C21—C22	1.528 (4)
C1—H1A	0.9700	C21—H21A	0.9700
C1—H1B	0.9700	C21—H21B	0.9700
C1—H1C	0.9700	C21—H21C	0.9700
O3—H3A	0.80 (3)	O23—H23A	0.79 (4)
O3—H3B	0.76 (3)	O23—H23B	0.78 (3)
N1—C5	1.327 (3)	N21—C25	1.324 (3)
N1—C3	1.385 (3)	N21—C23	1.379 (3)
N2—C5	1.335 (3)	N22—C25	1.330 (3)
N2—C4	1.360 (3)	N22—C24	1.362 (3)
N2—H2	0.81 (3)	N22—H22	0.81 (3)
C3—C4	1.353 (4)	C23—C24	1.350 (4)
C3—H3	0.9400	C23—H23	0.9400
C4—H4	0.9400	C24—H24	0.9400
C5—H5	0.9400	C25—H25	0.9400
N3—C6	1.336 (3)	N23—C26	1.339 (3)
N3—C10	1.346 (3)	N23—C30	1.340 (3)
C6—C7	1.381 (4)	C26—C27	1.373 (4)
C6—H6	0.9400	C26—H26	0.9400
C7—C8	1.374 (4)	C27—C28	1.375 (4)
C7—H7	0.9400	C27—H27	0.9400
C8—C9	1.385 (4)	C28—C29	1.386 (4)
C8—H8	0.9400	C28—H28	0.9400
C9—C10	1.378 (4)	C29—C30	1.382 (3)
C9—H9	0.9400	C29—H29	0.9400
C10—C11	1.508 (3)	C30—C31	1.499 (3)
C11—O5	1.238 (3)	C31—O25	1.240 (3)
C11—O4	1.266 (3)	C31—O24	1.268 (3)
O1—Cu1—N1	93.03 (8)	O21—Cu2—N21	93.27 (8)
O1—Cu1—O4	175.09 (8)	O21—Cu2—O24	168.85 (8)
N1—Cu1—O4	90.96 (8)	N21—Cu2—O24	90.81 (8)
O1—Cu1—N3	93.73 (8)	O21—Cu2—N23	93.27 (8)
N1—Cu1—N3	168.96 (9)	N21—Cu2—N23	170.93 (8)
O4—Cu1—N3	81.90 (8)	O24—Cu2—N23	81.64 (8)
O1—Cu1—O3	95.29 (8)	O21—Cu2—O23	97.94 (8)
N1—Cu1—O3	94.94 (8)	N21—Cu2—O23	91.39 (8)
O4—Cu1—O3	87.21 (7)	O24—Cu2—O23	92.33 (8)
N3—Cu1—O3	93.12 (8)	N23—Cu2—O23	93.91 (8)
C2—O1—Cu1	118.17 (18)	C22—O21—Cu2	115.70 (19)
C2—C1—H1A	109.5	C22—C21—H21A	109.5
C2—C1—H1B	109.5	C22—C21—H21B	109.5
H1A—C1—H1B	109.5	H21A—C21—H21B	109.5
C2—C1—H1C	109.5	C22—C21—H21C	109.5
H1A—C1—H1C	109.5	H21A—C21—H21C	109.5
H1B—C1—H1C	109.5	H21B—C21—H21C	109.5
O2—C2—O1	124.1 (3)	O22—C22—O21	124.1 (3)
O2—C2—C1	121.2 (3)	O22—C22—C21	121.0 (3)
O1—C2—C1	114.8 (3)	O21—C22—C21	114.8 (3)
Cu1—O3—H3A	124 (3)	Cu2—O23—H23A	128 (3)
Cu1—O3—H3B	115 (3)	Cu2—O23—H23B	117 (3)
H3A—O3—H3B	102 (4)	H23A—O23—H23B	100 (4)
C5—N1—C3	105.2 (2)	C25—N21—C23	105.5 (2)
C5—N1—Cu1	125.80 (18)	C25—N21—Cu2	125.37 (18)
C3—N1—Cu1	128.53 (18)	C23—N21—Cu2	129.15 (19)
C5—N2—C4	107.9 (2)	C25—N22—C24	107.8 (2)
C5—N2—H2	128 (2)	C25—N22—H22	128 (2)
C4—N2—H2	124 (2)	C24—N22—H22	124 (2)
C4—C3—N1	109.3 (2)	C24—C23—N21	109.2 (2)
C4—C3—H3	125.4	C24—C23—H23	125.4
N1—C3—H3	125.4	N21—C23—H23	125.4
C3—C4—N2	106.4 (2)	C23—C24—N22	106.4 (2)
C3—C4—H4	126.8	C23—C24—H24	126.8
N2—C4—H4	126.8	N22—C24—H24	126.8
N1—C5—N2	111.1 (2)	N21—C25—N22	111.1 (2)
N1—C5—H5	124.4	N21—C25—H25	124.4
N2—C5—H5	124.4	N22—C25—H25	124.4
C6—N3—C10	118.4 (2)	C26—N23—C30	118.6 (2)
C6—N3—Cu1	128.90 (19)	C26—N23—Cu2	128.74 (19)
C10—N3—Cu1	112.60 (17)	C30—N23—Cu2	112.62 (17)
N3—C6—C7	122.3 (3)	N23—C26—C27	122.4 (3)
N3—C6—H6	118.8	N23—C26—H26	118.8
C7—C6—H6	118.8	C27—C26—H26	118.8
C8—C7—C6	119.0 (3)	C26—C27—C28	119.1 (3)
C8—C7—H7	120.5	C26—C27—H27	120.5
C6—C7—H7	120.5	C28—C27—H27	120.5
C7—C8—C9	119.2 (3)	C27—C28—C29	119.2 (3)
C7—C8—H8	120.4	C27—C28—H28	120.4
C9—C8—H8	120.4	C29—C28—H28	120.4
C10—C9—C8	118.7 (3)	C30—C29—C28	118.6 (2)
C10—C9—H9	120.7	C30—C29—H29	120.7
C8—C9—H9	120.7	C28—C29—H29	120.7
N3—C10—C9	122.3 (2)	N23—C30—C29	122.2 (2)
N3—C10—C11	114.3 (2)	N23—C30—C31	114.5 (2)
C9—C10—C11	123.3 (2)	C29—C30—C31	123.3 (2)
O5—C11—O4	125.3 (2)	O25—C31—O24	124.9 (2)
O5—C11—C10	118.9 (2)	O25—C31—C30	119.0 (2)
O4—C11—C10	115.8 (2)	O24—C31—C30	116.1 (2)
C11—O4—Cu1	115.26 (16)	C31—O24—Cu2	115.06 (16)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3A···O2^i	0.80 (3)	1.99 (3)	2.790 (3)	173 (4)
O3—H3B···O5^ii	0.76 (3)	2.08 (3)	2.826 (3)	168 (4)
N2—H2···O25	0.81 (3)	1.96 (3)	2.758 (3)	173 (3)
O23—H23A···O22^i	0.79 (4)	2.01 (4)	2.792 (3)	169 (4)
O23—H23B···O25^iii	0.78 (3)	2.02 (3)	2.765 (3)	161 (4)
N22—H22···O5	0.81 (3)	1.96 (3)	2.767 (3)	173 (3)

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