Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807031169/hb2446sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536807031169/hb2446Isup2.hkl |
CCDC reference: 648383
Commercial CoSO4.7H2O, freshly prepared H2oxado (Nenwa, 2004), and K3[Co(C2O4)3].3H2O (Bailar & Jones, 1939), were mixed together in a ratio of 0.56 g (2 mmol):0.95 g (8 mmol):0.99 g (2 mmol) in water (120 ml) with stirring at room temperature. The resulting red-brown precipitate was discarded by filtration. Concentration of the filtrate by slow evaporation in the hood over three weeks yielded dark-red prisms of (I) that were filtered off and dried in air at room temperature.
The non-water H atoms were positioned geometrically (O—H = 0.84 Å, N—H = 0.86 Å) and refined as riding with Uiso(H) = 1.2 Ueq(N) or 1.5Ueq(O). All the water H atoms were first located in a difference Fourier map and then refined with distance restraints of O–H = 0.85 (3) Å and H···H = 1.39 (3) Å, and with equal Uiso(H). The highest peak and deepest hole in the final difference map are 0.55 Å from atom H6A and 0.29 Å from O5A, respectively.
Due to the disorder observed for the two oxygen sites (O5 and O6), no hydrogen atoms could be located for these O atoms.
Water clusters, encapsulated as crystal hydrates in various solid networks, were recently introduced as a new field of considerable scientific relevance, both in theoretical and in experimental studies (Ludwig, 2001; Infantes & Motherwell, 2002; Mascal et al., 2006). The point at stake relates to the need for a comprehensive analysis of hydrogen-bonded water clusters, (H2O)n, where n > 1. Infantes and Motherwell (2002) have selected the cluster patterns and sorted their structures into five broad classes designated D, R, C, T and L.
We describe here compound (I) as a salt of the rare complex cation, [Co(H2oxado)3]3+ (Bekaroglu et al., 1978; Bélombé et al., 1993; Nenwa, 2004). It is a transition metal complex system that crystallizes in a nanochannelled lattice encapsulating infinite tapes of cyclic water hexamers, and it provides, therefore, another well documented example to be added to category T of the aforementioned classification.
The constituent parts of (I) are depicted in Fig. 1. The pseudo-octahedral coordination in the complex cation is similar to the chiral geometries, and the bond lengths and angles compare within experimental error with those reported previously (Nenwa, 2004; Bekaroglu et al., 1978; Bélombé et al., 1993). The host lattice of the structure is realised by the ionic partners which are linked together via a three dimensional network of O–H···O and N–H···O hydrogen bonds. The ions of each kind pile up in an eclipsed sequence to generate the corresponding charged stacks. The electrically neutral scaffold thus constructed is characterized by infinite channels (ca 6.4 Å wide) oriented parallel to [100], and encapsulating twelve water molecules of crystallization per unit cell.
The projection of a unit cell of (I) in Fig. 2 shows the positioning of the water molecules within the channels, reminiscent of the structure of a silver salt reported recently (Bélombé et al., 2007). The oxalate ion is centrosymmetric. Thus, only one oxalate ion is present in the unit cell, the other species being represented twice. A short segment of a water tape in (I) viewed down [010] is shown in Fig. 3. One distinguishes, from the ellipsoid size, two types of water molecules per asymmetric unit. Those containing atoms O1, O2 and O3, positioned close to the periphery of the channels – due to their involvement in H-bonding to the ionic building blocks of the host lattice – may be dubbed "peripheral" waters. The reduced ellipsoid size of these O atoms reveals that they are well ordered. The water molecules with the atoms O4, O5A and O6A may be referred to as "central" waters, as they are located around the central axis of the channel. The ellipsoid extent of these O atoms indicates their high disorder, probably due to their increased mobility since they are less strongly bonded than their "peripheral" congeners.
Table 2 summarizes the three categories of H-bonds that are effective in this structure. O–H···O and N–H···O bridges interconnect the ionic partners amongst themselves into the three dimensional host lattice. Note that these bridges represent the most efficient ones, with the shortest O···O separation of 2.584 (4)Å linking an oxamide dioxime to an oxalate O atom, viz. O15···O43x (see Table 2 for symmetry code). Then, O–H···O and N–H···O bridges of medium efficiency interlink the "peripheral" water molecules to the ionic partners. Finally, O–H···O bridges weakly interconnect water molecules amongst themselves within the nanochannels.
For related literature, see: Bélombé et al. (1993, 2007); Bailar & Jones (1939); Bekaroglu et al. (1978); Infantes & Motherwell (2002); Ludwig (2001); Mascal et al. (2006); Nenwa (2004).
Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: WinGX (Farrugia, 1999).
[Co(C2H6N4O2)3]2(C2O4)(SO4)2·12H2O | Z = 1 |
Mr = 1314.78 | F(000) = 678 |
Triclinic, P1 | Dx = 1.698 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 9.4298 (10) Å | Cell parameters from 20047 reflections |
b = 11.7820 (12) Å | θ = 1.8–30.0° |
c = 12.8118 (13) Å | µ = 0.85 mm−1 |
α = 65.494 (2)° | T = 193 K |
β = 83.088 (2)° | Prism, red |
γ = 86.735 (2)° | 0.25 × 0.15 × 0.10 mm |
V = 1285.7 (2) Å3 |
Bruker APEX CCD diffractometer | 7453 independent reflections |
Radiation source: fine-focus sealed tube | 5173 reflections with I > 2s(I) |
Graphite monochromator | Rint = 0.056 |
ω scans | θmax = 30.0°, θmin = 1.8° |
Absorption correction: multi-scan (SADABS; Bruker, 2001) | h = −13→13 |
Tmin = 0.816, Tmax = 0.919 | k = −16→16 |
20047 measured reflections | l = −18→18 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.062 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.158 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.10 | w = 1/[σ2(Fo2) + (0.0654P)2 + 0.8468P] where P = (Fo2 + 2Fc2)/3 |
7453 reflections | (Δ/σ)max < 0.001 |
381 parameters | Δρmax = 0.91 e Å−3 |
12 restraints | Δρmin = −0.53 e Å−3 |
[Co(C2H6N4O2)3]2(C2O4)(SO4)2·12H2O | γ = 86.735 (2)° |
Mr = 1314.78 | V = 1285.7 (2) Å3 |
Triclinic, P1 | Z = 1 |
a = 9.4298 (10) Å | Mo Kα radiation |
b = 11.7820 (12) Å | µ = 0.85 mm−1 |
c = 12.8118 (13) Å | T = 193 K |
α = 65.494 (2)° | 0.25 × 0.15 × 0.10 mm |
β = 83.088 (2)° |
Bruker APEX CCD diffractometer | 7453 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2001) | 5173 reflections with I > 2s(I) |
Tmin = 0.816, Tmax = 0.919 | Rint = 0.056 |
20047 measured reflections |
R[F2 > 2σ(F2)] = 0.062 | 12 restraints |
wR(F2) = 0.158 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.10 | Δρmax = 0.91 e Å−3 |
7453 reflections | Δρmin = −0.53 e Å−3 |
381 parameters |
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. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
Co | 0.72701 (5) | 0.84049 (4) | 0.30836 (4) | 0.01529 (12) | |
N24 | 0.6030 (3) | 0.8386 (3) | 0.4406 (2) | 0.0171 (6) | |
N31 | 0.5850 (3) | 0.7379 (3) | 0.2960 (3) | 0.0189 (6) | |
N14 | 0.8825 (3) | 0.9315 (3) | 0.3172 (2) | 0.0178 (6) | |
N11 | 0.8492 (3) | 0.8491 (3) | 0.1742 (2) | 0.0189 (6) | |
N34 | 0.8108 (3) | 0.6788 (3) | 0.3867 (3) | 0.0202 (6) | |
N21 | 0.6281 (3) | 0.9941 (3) | 0.2389 (2) | 0.0189 (6) | |
C23 | 0.4943 (3) | 0.9156 (3) | 0.4158 (3) | 0.0174 (6) | |
C12 | 0.9796 (3) | 0.8860 (3) | 0.1652 (3) | 0.0181 (7) | |
C22 | 0.5210 (3) | 1.0192 (3) | 0.2997 (3) | 0.0191 (7) | |
C13 | 0.9951 (3) | 0.9473 (3) | 0.2431 (3) | 0.0180 (7) | |
C32 | 0.6064 (4) | 0.6183 (3) | 0.3411 (3) | 0.0207 (7) | |
C33 | 0.7511 (4) | 0.5856 (3) | 0.3794 (3) | 0.0215 (7) | |
N27 | 0.3745 (3) | 0.9059 (3) | 0.4837 (3) | 0.0241 (7) | |
H27B | 0.3629 | 0.8434 | 0.5522 | 0.029* | |
H27A | 0.3062 | 0.9620 | 0.4604 | 0.029* | |
N16 | 1.0876 (3) | 0.8716 (3) | 0.0946 (3) | 0.0262 (7) | |
H16A | 1.0736 | 0.8348 | 0.0494 | 0.031* | |
H16B | 1.1731 | 0.8989 | 0.0931 | 0.031* | |
N17 | 1.1079 (3) | 1.0139 (3) | 0.2339 (3) | 0.0261 (7) | |
H17B | 1.1107 | 1.0519 | 0.2800 | 0.031* | |
H17A | 1.1803 | 1.0203 | 0.1815 | 0.031* | |
N36 | 0.5106 (4) | 0.5328 (3) | 0.3572 (3) | 0.0321 (8) | |
H36A | 0.4242 | 0.5558 | 0.3366 | 0.039* | |
H36B | 0.5334 | 0.4531 | 0.3886 | 0.039* | |
N26 | 0.4420 (3) | 1.1219 (3) | 0.2664 (3) | 0.0265 (7) | |
H26A | 0.4604 | 1.1814 | 0.1969 | 0.032* | |
H26B | 0.3711 | 1.1307 | 0.3139 | 0.032* | |
N37 | 0.8072 (4) | 0.4730 (3) | 0.4041 (3) | 0.0344 (8) | |
H37B | 0.8927 | 0.4556 | 0.4280 | 0.041* | |
H37A | 0.7589 | 0.4155 | 0.3967 | 0.041* | |
O28 | 0.5724 (3) | 0.7321 (2) | 0.5422 (2) | 0.0207 (5) | |
H28 | 0.6444 | 0.7116 | 0.5790 | 0.031* | |
O35 | 0.4425 (2) | 0.7706 (2) | 0.2803 (2) | 0.0227 (5) | |
H35 | 0.4373 | 0.8282 | 0.2145 | 0.034* | |
O15 | 0.8358 (3) | 0.7791 (3) | 0.1115 (2) | 0.0252 (6) | |
H15 | 0.7532 | 0.7885 | 0.0908 | 0.038* | |
O38 | 0.9540 (3) | 0.6557 (3) | 0.4085 (2) | 0.0253 (6) | |
H38 | 0.9732 | 0.6906 | 0.4504 | 0.038* | |
O18 | 0.8796 (3) | 1.0069 (2) | 0.3777 (2) | 0.0227 (5) | |
H18 | 0.8734 | 0.9618 | 0.4488 | 0.034* | |
O25 | 0.6574 (3) | 1.0865 (2) | 0.1272 (2) | 0.0235 (5) | |
H25 | 0.7287 | 1.1276 | 0.1244 | 0.035* | |
S | 0.09424 (9) | 0.24928 (9) | 0.35902 (8) | 0.0222 (2) | |
O54 | 0.1647 (3) | 0.1248 (2) | 0.3908 (2) | 0.0251 (6) | |
O53 | 0.0244 (3) | 0.2839 (3) | 0.2537 (2) | 0.0303 (6) | |
O51 | 0.2052 (3) | 0.3409 (3) | 0.3414 (3) | 0.0377 (7) | |
O52 | −0.0110 (3) | 0.2428 (3) | 0.4557 (3) | 0.0329 (7) | |
C41 | 0.5668 (3) | 0.9661 (4) | 0.9842 (3) | 0.0222 (7) | |
O42 | 0.6460 (3) | 1.0302 (3) | 0.8951 (2) | 0.0261 (6) | |
O43 | 0.5845 (3) | 0.8550 (3) | 1.0492 (2) | 0.0274 (6) | |
O1 | 0.8832 (3) | 0.2297 (3) | 0.0879 (3) | 0.0339 (7) | |
O2 | 0.7212 (3) | 0.3062 (3) | 0.3112 (2) | 0.0296 (6) | |
O3 | 0.2201 (4) | 0.5849 (4) | 0.2797 (4) | 0.0605 (11) | |
O4 | 0.4136 (7) | 0.6487 (6) | 0.0773 (5) | 0.110 (2) | |
O5A | 0.8644 (7) | 0.4954 (6) | −0.0420 (6) | 0.0863 (19)* | 0.786 (7) |
O5B | 0.989 (3) | 0.449 (2) | −0.092 (2) | 0.0863 (19)* | 0.214 (7) |
O6A | 0.5585 (8) | 0.3823 (8) | 0.1243 (6) | 0.0709 (17)* | 0.637 (8) |
O6B | 0.6096 (14) | 0.4563 (13) | 0.1069 (11) | 0.0709 (17)* | 0.363 (8) |
H1O | 0.874 (7) | 0.299 (3) | 0.042 (4) | 0.094 (9)* | |
H2O | 0.936 (6) | 0.227 (6) | 0.133 (4) | 0.094 (9)* | |
H3O | 0.804 (3) | 0.289 (6) | 0.292 (5) | 0.094 (9)* | |
H4O | 0.685 (6) | 0.334 (6) | 0.247 (4) | 0.094 (9)* | |
H5O | 0.234 (8) | 0.616 (5) | 0.207 (2) | 0.094 (9)* | |
H6O | 0.191 (7) | 0.513 (3) | 0.296 (5) | 0.094 (9)* | |
H7O | 0.480 (6) | 0.657 (6) | 0.006 (4) | 0.094 (9)* | |
H8O | 0.366 (6) | 0.594 (5) | 0.069 (6) | 0.094 (9)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Co | 0.0097 (2) | 0.0186 (2) | 0.0200 (2) | 0.00156 (16) | −0.00084 (16) | −0.01075 (18) |
N24 | 0.0145 (13) | 0.0192 (14) | 0.0173 (14) | 0.0002 (11) | −0.0005 (11) | −0.0076 (11) |
N31 | 0.0127 (13) | 0.0198 (15) | 0.0249 (15) | 0.0013 (11) | −0.0013 (11) | −0.0103 (12) |
N14 | 0.0132 (13) | 0.0215 (15) | 0.0239 (15) | 0.0004 (11) | 0.0001 (11) | −0.0152 (13) |
N11 | 0.0162 (13) | 0.0250 (15) | 0.0209 (15) | −0.0005 (11) | −0.0022 (11) | −0.0147 (13) |
N34 | 0.0161 (14) | 0.0233 (15) | 0.0242 (15) | 0.0058 (11) | −0.0059 (11) | −0.0123 (13) |
N21 | 0.0152 (13) | 0.0212 (15) | 0.0187 (14) | −0.0010 (11) | −0.0010 (11) | −0.0068 (12) |
C23 | 0.0133 (15) | 0.0219 (17) | 0.0209 (17) | 0.0023 (12) | −0.0022 (12) | −0.0127 (14) |
C12 | 0.0144 (15) | 0.0211 (17) | 0.0202 (16) | 0.0016 (12) | −0.0018 (12) | −0.0102 (14) |
C22 | 0.0134 (15) | 0.0216 (17) | 0.0245 (18) | 0.0003 (12) | −0.0044 (13) | −0.0111 (14) |
C13 | 0.0136 (15) | 0.0207 (17) | 0.0219 (17) | 0.0040 (12) | −0.0035 (12) | −0.0110 (14) |
C32 | 0.0203 (17) | 0.0244 (18) | 0.0188 (17) | 0.0002 (13) | −0.0007 (13) | −0.0107 (14) |
C33 | 0.0201 (17) | 0.0228 (18) | 0.0250 (18) | 0.0050 (13) | −0.0061 (14) | −0.0128 (15) |
N27 | 0.0159 (14) | 0.0283 (17) | 0.0256 (16) | 0.0050 (12) | 0.0021 (12) | −0.0105 (13) |
N16 | 0.0123 (13) | 0.043 (2) | 0.0336 (18) | −0.0032 (13) | 0.0039 (12) | −0.0273 (16) |
N17 | 0.0149 (14) | 0.0404 (19) | 0.0333 (18) | −0.0059 (13) | 0.0038 (12) | −0.0264 (16) |
N36 | 0.0270 (17) | 0.0210 (16) | 0.047 (2) | −0.0032 (13) | −0.0104 (15) | −0.0103 (15) |
N26 | 0.0236 (16) | 0.0239 (16) | 0.0265 (17) | 0.0089 (13) | −0.0015 (13) | −0.0064 (13) |
N37 | 0.0310 (18) | 0.0237 (17) | 0.054 (2) | 0.0104 (14) | −0.0170 (17) | −0.0198 (17) |
O28 | 0.0161 (11) | 0.0223 (13) | 0.0199 (12) | 0.0009 (10) | −0.0023 (9) | −0.0049 (10) |
O35 | 0.0122 (11) | 0.0242 (13) | 0.0287 (14) | −0.0004 (9) | −0.0037 (10) | −0.0074 (11) |
O15 | 0.0138 (11) | 0.0390 (16) | 0.0359 (15) | 0.0017 (11) | −0.0035 (11) | −0.0285 (13) |
O38 | 0.0155 (12) | 0.0331 (15) | 0.0365 (15) | 0.0089 (10) | −0.0098 (11) | −0.0227 (13) |
O18 | 0.0224 (12) | 0.0263 (13) | 0.0261 (13) | −0.0015 (10) | 0.0020 (11) | −0.0184 (11) |
O25 | 0.0217 (13) | 0.0248 (13) | 0.0194 (13) | −0.0037 (10) | −0.0016 (10) | −0.0040 (10) |
S | 0.0178 (4) | 0.0249 (5) | 0.0301 (5) | 0.0048 (3) | −0.0093 (3) | −0.0163 (4) |
O54 | 0.0202 (12) | 0.0260 (14) | 0.0330 (15) | 0.0061 (10) | −0.0061 (11) | −0.0158 (12) |
O53 | 0.0246 (14) | 0.0374 (16) | 0.0311 (15) | 0.0051 (12) | −0.0116 (11) | −0.0147 (13) |
O51 | 0.0317 (16) | 0.0261 (15) | 0.055 (2) | −0.0019 (12) | −0.0212 (14) | −0.0120 (14) |
O52 | 0.0243 (14) | 0.0493 (18) | 0.0365 (16) | 0.0101 (13) | −0.0081 (12) | −0.0290 (15) |
C41 | 0.0110 (15) | 0.038 (2) | 0.0225 (18) | −0.0025 (14) | −0.0052 (13) | −0.0156 (16) |
O42 | 0.0152 (12) | 0.0383 (16) | 0.0249 (14) | −0.0030 (11) | 0.0046 (10) | −0.0143 (12) |
O43 | 0.0189 (13) | 0.0346 (15) | 0.0282 (14) | −0.0003 (11) | −0.0052 (11) | −0.0118 (12) |
O1 | 0.0319 (16) | 0.0387 (17) | 0.0354 (17) | −0.0066 (13) | −0.0050 (13) | −0.0183 (14) |
O2 | 0.0196 (13) | 0.0339 (16) | 0.0347 (16) | 0.0010 (11) | 0.0004 (11) | −0.0147 (13) |
O3 | 0.047 (2) | 0.038 (2) | 0.098 (3) | −0.0035 (17) | −0.010 (2) | −0.029 (2) |
O4 | 0.139 (5) | 0.105 (5) | 0.084 (4) | −0.056 (4) | −0.030 (4) | −0.024 (3) |
Co—N21 | 1.900 (3) | N17—H17B | 0.8800 |
Co—N14 | 1.906 (3) | N17—H17A | 0.8800 |
Co—N31 | 1.917 (3) | N36—H36A | 0.8800 |
Co—N11 | 1.920 (3) | N36—H36B | 0.8800 |
Co—N34 | 1.922 (3) | N26—H26A | 0.8800 |
Co—N24 | 1.932 (3) | N26—H26B | 0.8800 |
N24—C23 | 1.307 (4) | N37—H37B | 0.8800 |
N24—O28 | 1.396 (4) | N37—H37A | 0.8800 |
N31—C32 | 1.297 (4) | O28—H28 | 0.8400 |
N31—O35 | 1.391 (3) | O35—H35 | 0.8400 |
N14—C13 | 1.302 (4) | O15—H15 | 0.8400 |
N14—O18 | 1.398 (3) | O38—H38 | 0.8400 |
N11—C12 | 1.303 (4) | O18—H18 | 0.8400 |
N11—O15 | 1.388 (4) | O25—H25 | 0.8400 |
N34—C33 | 1.303 (4) | S—O53 | 1.465 (3) |
N34—O38 | 1.400 (3) | S—O52 | 1.469 (3) |
N21—C22 | 1.297 (4) | S—O51 | 1.477 (3) |
N21—O25 | 1.398 (4) | S—O54 | 1.489 (3) |
C23—N27 | 1.319 (4) | C41—O43 | 1.241 (5) |
C23—C22 | 1.485 (5) | C41—O42 | 1.255 (4) |
C12—N16 | 1.330 (4) | C41—C41i | 1.555 (7) |
C12—C13 | 1.478 (5) | O1—H1O | 0.79 (3) |
C22—N26 | 1.321 (4) | O1—H2O | 0.80 (3) |
C13—N17 | 1.323 (4) | O2—H3O | 0.83 (3) |
C32—N36 | 1.327 (5) | O2—H4O | 0.85 (3) |
C32—C33 | 1.482 (5) | O3—H5O | 0.84 (3) |
C33—N37 | 1.324 (5) | O3—H6O | 0.84 (3) |
N27—H27B | 0.8800 | O4—H7O | 1.01 (3) |
N27—H27A | 0.8800 | O4—H8O | 0.85 (3) |
N16—H16A | 0.8800 | O5A—O5B | 1.45 (2) |
N16—H16B | 0.8800 | O6A—O6B | 0.950 (13) |
N21—Co—N14 | 88.61 (12) | N17—C13—C12 | 123.1 (3) |
N21—Co—N31 | 96.04 (12) | N31—C32—N36 | 125.4 (3) |
N14—Co—N31 | 174.13 (12) | N31—C32—C33 | 111.9 (3) |
N21—Co—N11 | 97.98 (12) | N36—C32—C33 | 122.6 (3) |
N14—Co—N11 | 79.99 (12) | N34—C33—N37 | 126.2 (3) |
N31—Co—N11 | 95.78 (12) | N34—C33—C32 | 111.9 (3) |
N21—Co—N34 | 174.77 (12) | N37—C33—C32 | 121.9 (3) |
N14—Co—N34 | 95.29 (12) | C23—N27—H27B | 120.0 |
N31—Co—N34 | 80.29 (12) | C23—N27—H27A | 120.0 |
N11—Co—N34 | 86.15 (13) | H27B—N27—H27A | 120.0 |
N21—Co—N24 | 79.98 (12) | C12—N16—H16A | 120.0 |
N14—Co—N24 | 99.14 (12) | C12—N16—H16B | 120.0 |
N31—Co—N24 | 85.24 (12) | H16A—N16—H16B | 120.0 |
N11—Co—N24 | 177.82 (13) | C13—N17—H17B | 120.0 |
N34—Co—N24 | 95.93 (12) | C13—N17—H17A | 120.0 |
C23—N24—O28 | 112.3 (3) | H17B—N17—H17A | 120.0 |
C23—N24—Co | 114.8 (2) | C32—N36—H36A | 120.0 |
O28—N24—Co | 124.3 (2) | C32—N36—H36B | 120.0 |
C32—N31—O35 | 113.0 (3) | H36A—N36—H36B | 120.0 |
C32—N31—Co | 117.3 (2) | C22—N26—H26A | 120.0 |
O35—N31—Co | 125.9 (2) | C22—N26—H26B | 120.0 |
C13—N14—O18 | 113.8 (3) | H26A—N26—H26B | 120.0 |
C13—N14—Co | 117.9 (2) | C33—N37—H37B | 120.0 |
O18—N14—Co | 126.8 (2) | C33—N37—H37A | 120.0 |
C12—N11—O15 | 112.9 (3) | H37B—N37—H37A | 120.0 |
C12—N11—Co | 116.3 (2) | N24—O28—H28 | 109.5 |
O15—N11—Co | 126.0 (2) | N31—O35—H35 | 109.5 |
C33—N34—O38 | 113.0 (3) | N11—O15—H15 | 109.5 |
C33—N34—Co | 116.2 (2) | N34—O38—H38 | 109.5 |
O38—N34—Co | 125.5 (2) | N14—O18—H18 | 109.5 |
C22—N21—O25 | 114.6 (3) | N21—O25—H25 | 109.5 |
C22—N21—Co | 118.1 (2) | O53—S—O52 | 110.50 (16) |
O25—N21—Co | 127.3 (2) | O53—S—O51 | 110.43 (18) |
N24—C23—N27 | 125.7 (3) | O52—S—O51 | 109.38 (18) |
N24—C23—C22 | 111.6 (3) | O53—S—O54 | 110.55 (16) |
N27—C23—C22 | 122.7 (3) | O52—S—O54 | 108.07 (17) |
N11—C12—N16 | 124.9 (3) | O51—S—O54 | 107.84 (16) |
N11—C12—C13 | 112.0 (3) | O43—C41—O42 | 126.7 (3) |
N16—C12—C13 | 123.0 (3) | O43—C41—C41i | 117.1 (4) |
N21—C22—N26 | 126.4 (3) | O42—C41—C41i | 116.2 (4) |
N21—C22—C23 | 111.4 (3) | H1O—O1—H2O | 111 (4) |
N26—C22—C23 | 122.2 (3) | H3O—O2—H4O | 101 (4) |
N14—C13—N17 | 125.2 (3) | H5O—O3—H6O | 103 (4) |
N14—C13—C12 | 111.7 (3) | H7O—O4—H8O | 90 (3) |
Symmetry code: (i) −x+1, −y+2, −z+2. |
D—H···A | D—H | H···A | D···A | D—H···A |
N16—H16B···O42ii | 0.88 | 1.99 | 2.864 (4) | 172 |
N17—H17B···O54iii | 0.88 | 2.06 | 2.926 (4) | 167 |
N17—H17A···O42ii | 0.88 | 2.00 | 2.835 (4) | 159 |
N27—H27A···O54iv | 0.88 | 2.20 | 3.069 (4) | 170 |
N26—H26B···O54iv | 0.88 | 2.06 | 2.900 (4) | 158 |
N36—H36B···O28v | 0.88 | 2.23 | 2.952 (4) | 139 |
N37—H37B···O52vi | 0.88 | 2.51 | 2.998 (4) | 115 |
N37—H37B···O38vii | 0.88 | 2.54 | 3.321 (4) | 149 |
O15—H15···O43viii | 0.84 | 1.77 | 2.584 (4) | 162 |
O18—H18···O54v | 0.84 | 1.88 | 2.709 (4) | 172 |
O18—H18···O52v | 0.84 | 2.56 | 3.124 (4) | 125 |
O28—H28···O51v | 0.84 | 1.78 | 2.617 (4) | 177 |
O35—H35···O42ix | 0.84 | 1.88 | 2.667 (4) | 155 |
O35—H35···O43viii | 0.84 | 2.30 | 2.881 (4) | 127 |
O38—H38···O52v | 0.84 | 1.76 | 2.602 (4) | 177 |
N16—H16A···O1x | 0.88 | 2.18 | 3.016 (4) | 159 |
N27—H27B···O2v | 0.88 | 2.02 | 2.865 (4) | 162 |
N36—H36A···O3 | 0.88 | 2.10 | 2.971 (5) | 170 |
N37—H37A···O2 | 0.88 | 2.07 | 2.879 (5) | 152 |
O25—H25···O1iv | 0.84 | 1.83 | 2.662 (4) | 169 |
O1—H2O···O53vi | 0.80 (3) | 2.19 (4) | 2.931 (4) | 156 (6) |
O2—H3O···O53vi | 0.83 (3) | 2.08 (3) | 2.890 (4) | 165 (6) |
O3—H6O···O51 | 0.84 (3) | 1.87 (4) | 2.653 (5) | 157 (7) |
O1—H1O···O5A | 0.79 (3) | 2.11 (3) | 2.879 (7) | 164 (6) |
O2—H4O···O6A | 0.85 (3) | 1.96 (3) | 2.799 (8) | 166 (6) |
O3—H5O···O4 | 0.84 (3) | 2.16 (6) | 2.831 (8) | 137 (7) |
O4—H7O···O6Axi | 1.01 (3) | 1.99 (6) | 2.736 (9) | 128 (5) |
O4—H8O···O5Axi | 0.85 (3) | 2.59 (4) | 3.375 (8) | 153 (6) |
Symmetry codes: (ii) −x+2, −y+2, −z+1; (iii) x+1, y+1, z; (iv) x, y+1, z; (v) −x+1, −y+1, −z+1; (vi) x+1, y, z; (vii) −x+2, −y+1, −z+1; (viii) x, y, z−1; (ix) −x+1, −y+2, −z+1; (x) −x+2, −y+1, −z; (xi) −x+1, −y+1, −z. |
Experimental details
Crystal data | |
Chemical formula | [Co(C2H6N4O2)3]2(C2O4)(SO4)2·12H2O |
Mr | 1314.78 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 193 |
a, b, c (Å) | 9.4298 (10), 11.7820 (12), 12.8118 (13) |
α, β, γ (°) | 65.494 (2), 83.088 (2), 86.735 (2) |
V (Å3) | 1285.7 (2) |
Z | 1 |
Radiation type | Mo Kα |
µ (mm−1) | 0.85 |
Crystal size (mm) | 0.25 × 0.15 × 0.10 |
Data collection | |
Diffractometer | Bruker APEX CCD |
Absorption correction | Multi-scan (SADABS; Bruker, 2001) |
Tmin, Tmax | 0.816, 0.919 |
No. of measured, independent and observed [I > 2s(I)] reflections | 20047, 7453, 5173 |
Rint | 0.056 |
(sin θ/λ)max (Å−1) | 0.704 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.062, 0.158, 1.10 |
No. of reflections | 7453 |
No. of parameters | 381 |
No. of restraints | 12 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.91, −0.53 |
Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 2000), SAINT, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), DIAMOND (Brandenburg, 1999), WinGX (Farrugia, 1999).
Co—N21 | 1.900 (3) | Co—N11 | 1.920 (3) |
Co—N14 | 1.906 (3) | Co—N34 | 1.922 (3) |
Co—N31 | 1.917 (3) | Co—N24 | 1.932 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
N16—H16B···O42i | 0.88 | 1.99 | 2.864 (4) | 172 |
N17—H17B···O54ii | 0.88 | 2.06 | 2.926 (4) | 167 |
N17—H17A···O42i | 0.88 | 2.00 | 2.835 (4) | 159 |
N27—H27A···O54iii | 0.88 | 2.20 | 3.069 (4) | 170 |
N26—H26B···O54iii | 0.88 | 2.06 | 2.900 (4) | 158 |
N36—H36B···O28iv | 0.88 | 2.23 | 2.952 (4) | 139 |
N37—H37B···O52v | 0.88 | 2.51 | 2.998 (4) | 115 |
N37—H37B···O38vi | 0.88 | 2.54 | 3.321 (4) | 149 |
O15—H15···O43vii | 0.84 | 1.77 | 2.584 (4) | 162 |
O18—H18···O54iv | 0.84 | 1.88 | 2.709 (4) | 172 |
O18—H18···O52iv | 0.84 | 2.56 | 3.124 (4) | 125 |
O28—H28···O51iv | 0.84 | 1.78 | 2.617 (4) | 177 |
O35—H35···O42viii | 0.84 | 1.88 | 2.667 (4) | 155 |
O35—H35···O43vii | 0.84 | 2.30 | 2.881 (4) | 127 |
O38—H38···O52iv | 0.84 | 1.76 | 2.602 (4) | 177 |
N16—H16A···O1ix | 0.88 | 2.18 | 3.016 (4) | 159 |
N27—H27B···O2iv | 0.88 | 2.02 | 2.865 (4) | 162 |
N36—H36A···O3 | 0.88 | 2.10 | 2.971 (5) | 170 |
N37—H37A···O2 | 0.88 | 2.07 | 2.879 (5) | 152 |
O25—H25···O1iii | 0.84 | 1.83 | 2.662 (4) | 169 |
O1—H2O···O53v | 0.80 (3) | 2.19 (4) | 2.931 (4) | 156 (6) |
O2—H3O···O53v | 0.83 (3) | 2.08 (3) | 2.890 (4) | 165 (6) |
O3—H6O···O51 | 0.84 (3) | 1.87 (4) | 2.653 (5) | 157 (7) |
O1—H1O···O5A | 0.79 (3) | 2.11 (3) | 2.879 (7) | 164 (6) |
O2—H4O···O6A | 0.85 (3) | 1.96 (3) | 2.799 (8) | 166 (6) |
O3—H5O···O4 | 0.84 (3) | 2.16 (6) | 2.831 (8) | 137 (7) |
O4—H7O···O6Ax | 1.01 (3) | 1.99 (6) | 2.736 (9) | 128 (5) |
O4—H8O···O5Ax | 0.85 (3) | 2.59 (4) | 3.375 (8) | 153 (6) |
Symmetry codes: (i) −x+2, −y+2, −z+1; (ii) x+1, y+1, z; (iii) x, y+1, z; (iv) −x+1, −y+1, −z+1; (v) x+1, y, z; (vi) −x+2, −y+1, −z+1; (vii) x, y, z−1; (viii) −x+1, −y+2, −z+1; (ix) −x+2, −y+1, −z; (x) −x+1, −y+1, −z. |
Water clusters, encapsulated as crystal hydrates in various solid networks, were recently introduced as a new field of considerable scientific relevance, both in theoretical and in experimental studies (Ludwig, 2001; Infantes & Motherwell, 2002; Mascal et al., 2006). The point at stake relates to the need for a comprehensive analysis of hydrogen-bonded water clusters, (H2O)n, where n > 1. Infantes and Motherwell (2002) have selected the cluster patterns and sorted their structures into five broad classes designated D, R, C, T and L.
We describe here compound (I) as a salt of the rare complex cation, [Co(H2oxado)3]3+ (Bekaroglu et al., 1978; Bélombé et al., 1993; Nenwa, 2004). It is a transition metal complex system that crystallizes in a nanochannelled lattice encapsulating infinite tapes of cyclic water hexamers, and it provides, therefore, another well documented example to be added to category T of the aforementioned classification.
The constituent parts of (I) are depicted in Fig. 1. The pseudo-octahedral coordination in the complex cation is similar to the chiral geometries, and the bond lengths and angles compare within experimental error with those reported previously (Nenwa, 2004; Bekaroglu et al., 1978; Bélombé et al., 1993). The host lattice of the structure is realised by the ionic partners which are linked together via a three dimensional network of O–H···O and N–H···O hydrogen bonds. The ions of each kind pile up in an eclipsed sequence to generate the corresponding charged stacks. The electrically neutral scaffold thus constructed is characterized by infinite channels (ca 6.4 Å wide) oriented parallel to [100], and encapsulating twelve water molecules of crystallization per unit cell.
The projection of a unit cell of (I) in Fig. 2 shows the positioning of the water molecules within the channels, reminiscent of the structure of a silver salt reported recently (Bélombé et al., 2007). The oxalate ion is centrosymmetric. Thus, only one oxalate ion is present in the unit cell, the other species being represented twice. A short segment of a water tape in (I) viewed down [010] is shown in Fig. 3. One distinguishes, from the ellipsoid size, two types of water molecules per asymmetric unit. Those containing atoms O1, O2 and O3, positioned close to the periphery of the channels – due to their involvement in H-bonding to the ionic building blocks of the host lattice – may be dubbed "peripheral" waters. The reduced ellipsoid size of these O atoms reveals that they are well ordered. The water molecules with the atoms O4, O5A and O6A may be referred to as "central" waters, as they are located around the central axis of the channel. The ellipsoid extent of these O atoms indicates their high disorder, probably due to their increased mobility since they are less strongly bonded than their "peripheral" congeners.
Table 2 summarizes the three categories of H-bonds that are effective in this structure. O–H···O and N–H···O bridges interconnect the ionic partners amongst themselves into the three dimensional host lattice. Note that these bridges represent the most efficient ones, with the shortest O···O separation of 2.584 (4)Å linking an oxamide dioxime to an oxalate O atom, viz. O15···O43x (see Table 2 for symmetry code). Then, O–H···O and N–H···O bridges of medium efficiency interlink the "peripheral" water molecules to the ionic partners. Finally, O–H···O bridges weakly interconnect water molecules amongst themselves within the nanochannels.