Hexaquacobalt(II) bis­(isonicotinate N-oxide): a redetermination and analysis of the hydrogen-bonding interactions

In the crystal structure of the title complex, [Co(H₂O)₆](L)₂ (L = isonicotinate N-oxide, C₆H₄NO₃), the Co^II center, on a special position with site symmetry 2/m, is in an elongated octahedral environment composed of six coord­inated water mol­ecules. Each water ligand forms two strong O—H...O hydrogen bonds with the adjacent isonicotinate N-oxide counter-ions, which lie on mirror planes, forming a three-dimensional hydrogen-bonding supramolecular architecture.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.036
• wR factor = 0.082
• Data-to-parameter ratio = 15.1

checkCIF/PLATON results

No syntax errors found



Alert level A
PLAT242_ALERT_2_A Check Low    U(eq) as Compared to Neighbors ....        Co1

Alert level B
PLAT213_ALERT_2_B Atom O2      has ADP max/min Ratio .............       4.30 prolat
PLAT250_ALERT_2_B Large U3/U1 Ratio for Average U(i,j) Tensor ....       4.62

Alert level C
PLAT213_ALERT_2_C Atom O3      has ADP max/min Ratio .............       3.10 prolat
PLAT213_ALERT_2_C Atom O4      has ADP max/min Ratio .............       3.40 prolat
PLAT220_ALERT_2_C Large Non-Solvent    C     Ueq(max)/Ueq(min) ...       2.55 Ratio
PLAT241_ALERT_2_C Check High   U(eq) as Compared to Neighbors ....         C1
PLAT242_ALERT_2_C Check Low    U(eq) as Compared to Neighbors ....         N1
PLAT242_ALERT_2_C Check Low    U(eq) as Compared to Neighbors ....         C3
PLAT480_ALERT_4_C Long H...A H-Bond Reported H4B    ..  N1      ..       2.67 Ang.
PLAT764_ALERT_4_C Overcomplete CIF Bond List Detected (Rep/Expd) .       1.15 Ratio

Alert level G
REFLT03_ALERT_1_G ALERT: Expected hkl max differ from CIF values
           From the CIF: _diffrn_reflns_theta_max           28.03
           From the CIF: _reflns_number_total               1086
           From the CIF: _diffrn_reflns_limit_ max hkl   13.    9.    9.
           From the CIF: _diffrn_reflns_limit_ min hkl   -8.  -11.   -9.
           TEST1: Expected hkl limits for theta max
           Calculated maximum hkl   15.   12.   10.
           Calculated minimum hkl  -15.  -12.  -10.

   1 ALERT level A = In general: serious problem
   2 ALERT level B = Potentially serious problem
   8 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
   9 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: SMART (Bruker, 1998); cell refinement: SMART; data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Brandenburg & Berndt, 1999); software used to prepare material for publication: SHELXL97.

(I)

Crystal data

[Co(H2O)6](C6H4NO3)2	F(000) = 458
Mr = 443.23	Dx = 1.705 Mg m^−3
Monoclinic, C2/m	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2y	Cell parameters from 756 reflections
a = 11.425 (4) Å	θ = 2.7–28.0°
b = 9.780 (4) Å	µ = 1.06 mm^−1
c = 7.726 (3) Å	T = 293 K
β = 90.967 (6)°	Block, pink
V = 863.2 (6) Å^3	0.28 × 0.20 × 0.12 mm
Z = 2

Data collection

Bruker SMART CCD area-detector diffractometer	1086 independent reflections
Radiation source: fine-focus sealed tube	1061 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.019
φ and ω scans	θmax = 28.0°, θmin = 2.6°
Absorption correction: multi-scan (SADABS; Sheldrick, 1997)	h = −8→13
Tmin = 0.688, Tmax = 0.880	k = −11→9
2775 measured reflections	l = −9→9

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)] = 0.036	H-atom parameters constrained
wR(F^2) = 0.082	w = 1/[σ^2(Fo^2) + (0.0203P)^2 + 2.5192P] where P = (Fo^2 + 2Fc^2)/3
S = 1.01	(Δ/σ)max < 0.001
1086 reflections	Δρmax = 0.56 e Å^−3
72 parameters	Δρmin = −0.41 e Å^−3
2 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: 0.0032 (9)

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
Co1	0.5000	0.5000	0.5000	0.02533 (18)
C1	0.8275 (3)	0.6162 (4)	0.1438 (5)	0.0842 (12)
H1	0.7884	0.6982	0.1233	0.101*
C2	0.9402 (2)	0.6183 (3)	0.2079 (4)	0.0681 (9)
H2	0.9770	0.7016	0.2292	0.082*
C3	0.9983 (2)	0.5000	0.2403 (4)	0.0336 (6)
C4	1.1224 (2)	0.5000	0.3097 (4)	0.0330 (6)
N1	0.7740 (2)	0.5000	0.1112 (4)	0.0649 (12)
O1	1.16996 (14)	0.38743 (18)	0.3336 (3)	0.0533 (5)
O2	0.6669 (2)	0.5000	0.0443 (3)	0.1031 (16)
O3	0.63001 (15)	0.6422 (2)	0.4881 (3)	0.0761 (8)
H3A	0.6927	0.6311	0.5465	0.114*
H3B	0.6330	0.7173	0.4352	0.114*
O4	0.5190 (2)	0.5000	0.7654 (3)	0.0975 (15)
H4A	0.5770	0.5000	0.8359	0.146*
H4B	0.4545	0.5000	0.8187	0.146*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Co1	0.0175 (3)	0.0266 (3)	0.0317 (3)	0.000	−0.00609 (18)	0.000
C1	0.0472 (16)	0.105 (3)	0.099 (3)	0.0381 (18)	−0.0328 (17)	−0.022 (2)
C2	0.0453 (15)	0.0605 (18)	0.097 (2)	0.0203 (13)	−0.0331 (15)	−0.0225 (17)
C3	0.0239 (13)	0.0481 (18)	0.0287 (14)	0.000	−0.0049 (10)	0.000
C4	0.0245 (13)	0.0407 (16)	0.0336 (14)	0.000	−0.0079 (11)	0.000
N1	0.0203 (13)	0.146 (4)	0.0279 (14)	0.000	−0.0060 (10)	0.000
O1	0.0354 (8)	0.0388 (9)	0.0850 (13)	−0.0024 (7)	−0.0247 (8)	0.0169 (9)
O2	0.0191 (11)	0.254 (5)	0.0356 (14)	0.000	−0.0108 (10)	0.000
O3	0.0404 (10)	0.0561 (12)	0.1302 (19)	−0.0250 (9)	−0.0475 (11)	0.0491 (13)
O4	0.0277 (13)	0.233 (5)	0.0313 (13)	0.000	−0.0084 (10)	0.000

Geometric parameters (Å, º)

Co1—O3^i	2.0378 (18)	C3—C2^ii	1.356 (3)
Co1—O3	2.0378 (18)	C3—C4	1.507 (4)
Co1—O3^ii	2.0378 (18)	C4—O1^ii	1.240 (2)
Co1—O3^iii	2.0378 (18)	C4—O1	1.240 (2)
Co1—O4^i	2.059 (3)	N1—C1^ii	1.313 (4)
Co1—O4	2.059 (3)	N1—O2	1.320 (3)
C1—N1	1.313 (4)	O3—H3A	0.8470
C1—C2	1.372 (4)	O3—H3B	0.8413
C1—H1	0.9300	O4—H4A	0.8500
C2—C3	1.356 (3)	O4—H4B	0.8500
C2—H2	0.9300
O3^i—Co1—O3	180.00 (8)	C3—C2—C1	120.5 (3)
O3^i—Co1—O3^ii	93.95 (13)	C3—C2—H2	119.8
O3—Co1—O3^ii	86.05 (13)	C1—C2—H2	119.8
O3^i—Co1—O3^iii	86.05 (13)	C2^ii—C3—C2	117.2 (3)
O3—Co1—O3^iii	93.95 (13)	C2^ii—C3—C4	121.39 (16)
O3^ii—Co1—O3^iii	180.0	C2—C3—C4	121.39 (16)
O3^i—Co1—O4^i	88.87 (9)	O1^ii—C4—O1	125.2 (3)
O3—Co1—O4^i	91.13 (9)	O1^ii—C4—C3	117.40 (13)
O3^ii—Co1—O4^i	91.13 (9)	O1—C4—C3	117.40 (13)
O3^iii—Co1—O4^i	88.87 (9)	C1—N1—C1^ii	119.9 (3)
O3^i—Co1—O4	91.13 (9)	C1—N1—O2	120.06 (16)
O3—Co1—O4	88.87 (9)	C1^ii—N1—O2	120.06 (16)
O3^ii—Co1—O4	88.87 (9)	Co1—O3—H3A	119.9
O3^iii—Co1—O4	91.13 (9)	Co1—O3—H3B	130.7
O4^i—Co1—O4	180.0	H3A—O3—H3B	109.3
N1—C1—C2	120.9 (3)	Co1—O4—H4A	134.9
N1—C1—H1	119.5	Co1—O4—H4B	113.9
C2—C1—H1	119.5	H4A—O4—H4B	111.2
N1—C1—C2—C3	−0.6 (6)	C2^ii—C3—C4—O1	1.1 (5)
C1—C2—C3—C2^ii	−0.4 (6)	C2—C3—C4—O1	−179.0 (3)
C1—C2—C3—C4	179.7 (3)	C2—C1—N1—C1^ii	1.7 (7)
C2^ii—C3—C4—O1^ii	179.0 (3)	C2—C1—N1—O2	−177.8 (3)
C2—C3—C4—O1^ii	−1.1 (5)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O4—H4B···N1^i	0.85	2.67	3.495 (4)	163
O4—H4B···O2^i	0.85	1.76	2.603 (4)	172
O4—H4A···O2^iv	0.85	1.90	2.715 (4)	161
O3—H3B···O1^v	0.84	1.89	2.721 (3)	169
O3—H3A···O1^vi	0.85	1.82	2.664 (2)	178

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