Hexaaqua­cobalt(II) bis­(6-hydroxy­pyridine-3-carboxyl­ate)

In the title compound, [Co(H₂O)₆](C₆H₄NO₃)₂, the Co^II atom lies on a special position of 2/m site symmetry in an octa­hedron made up of water mol­ecules. The anions show orientational disorder over mirror planes and are linked together by a pair of N—H...O hydrogen bonds into a dianion. The complex cations and dianions are connected through O—H...O hydrogen bonds to form a three-dimensional network.

Key indicators

• Single-crystal X-ray study
• T = 295 K
• Mean [sigma](o-O) = 0.004 Å
• Disorder in main residue
• R factor = 0.054
• wR factor = 0.159
• Data-to-parameter ratio = 8.6

checkCIF/PLATON results

No syntax errors found



Alert level A
PLAT029_ALERT_3_A _diffrn_measured_fraction_theta_full Low .......       0.93

Author Response: The fraction is low at 55\% but is 96% at 50\%.

Alert level B
ABSTM02_ALERT_3_B  The ratio of expected to reported Tmax/Tmin(RR') is < 0.75
            Tmin and Tmax reported:      0.499     0.920
            Tmin' and Tmax expected:      0.692     0.918
            RR' =      0.720
            Please check that your absorption correction is appropriate.
PLAT061_ALERT_3_B Tmax/Tmin Range Test RR' too Large .............       0.71
PLAT242_ALERT_2_B Check Low       Ueq as Compared to Neighbors for        Co1
PLAT301_ALERT_3_B Main Residue  Disorder .........................      29.00 Perc.
PLAT731_ALERT_1_B Bond    Calc     0.85(5), Rep   0.850(10) ......       5.00 su-Rat
              O2W  -H2W2    1.555   1.555
PLAT735_ALERT_1_B D-H     Calc     0.85(5), Rep   0.850(10) ......       5.00 su-Rat
              O2W  -H4#     1.555   1.555
PLAT735_ALERT_1_B D-H     Calc     0.85(5), Rep   0.850(10) ......       5.00 su-Rat
              O2W  -H4#     1.555   1.555

Alert level C
REFLT03_ALERT_3_C  Reflection count < 95% complete
           From the CIF: _diffrn_reflns_theta_max           27.40
           From the CIF: _diffrn_reflns_theta_full          27.40
           From the CIF: _reflns_number_total                968
           TEST2: Reflns within _diffrn_reflns_theta_max
           Count of symmetry unique reflns         1041
           Completeness (_total/calc)             92.99%
PLAT022_ALERT_3_C Ratio Unique / Expected Reflections too Low ....       0.93
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT088_ALERT_3_C Poor Data / Parameter Ratio ....................       8.57
PLAT152_ALERT_1_C Supplied and Calc Volume s.u. Inconsistent .....          ?
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.05
PLAT720_ALERT_4_C Number of Unusual/Non-Standard Label(s) ........          4
PLAT731_ALERT_1_C Bond    Calc     0.85(3), Rep   0.850(10) ......       3.00 su-Rat
              O1W  -H1W1    1.555   1.555
PLAT731_ALERT_1_C Bond    Calc     0.84(3), Rep   0.840(10) ......       3.00 su-Rat
              O1W  -H1W2    1.555   1.555
PLAT731_ALERT_1_C Bond    Calc     0.85(4), Rep   0.850(10) ......       4.00 su-Rat
              O2W  -H2W1    1.555   1.555
PLAT732_ALERT_1_C Angle   Calc      110(5), Rep      110(2) ......       2.50 su-Rat
              H2W1 -O2W  -H2W2    1.555   1.555   1.555
PLAT735_ALERT_1_C D-H     Calc     0.85(3), Rep   0.850(10) ......       3.00 su-Rat
              O1W  -H1#     1.555   1.555
PLAT735_ALERT_1_C D-H     Calc     0.84(3), Rep   0.840(10) ......       3.00 su-Rat
              O1W  -H2#     1.555   1.555
PLAT735_ALERT_1_C D-H     Calc     0.85(4), Rep   0.850(10) ......       4.00 su-Rat
              O2W  -H3#     1.555   1.555
PLAT735_ALERT_1_C D-H     Calc     0.85(4), Rep   0.850(10) ......       4.00 su-Rat
              O2W  -H3#     1.555   1.555
PLAT736_ALERT_1_C H...A   Calc     1.87(3), Rep   1.870(10) ......       3.00 su-Rat
              H2#  -O1      1.555   7.666
PLAT764_ALERT_4_C Overcomplete CIF Bond List Detected (Rep/Expd) .       1.13 Ratio

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

  14 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   2 ALERT type 2 Indicator that the structure model may be wrong or deficient
   7 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, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT; program(s) used to solve structure: atomic coordinates taken from the isostructural Zn analogue (Zhang et al., 2005); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97.

Hexaaquacobalt(II) bis(6-hydroxypyridine-3-carboxylate)

Crystal data

[Co(H2O)6](C6H4NO3)2	F(000) = 458
Mr = 443.23	Dx = 1.707 Mg m^−3
Monoclinic, C2/m	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 1422 reflections
a = 11.609 (1) Å	θ = 2.7–27.4°
b = 9.754 (1) Å	µ = 1.07 mm^−1
c = 7.6157 (8) Å	T = 295 K
β = 91.448 (2)°	Plate, red
V = 862.1 (2) Å^3	0.34 × 0.20 × 0.08 mm
Z = 2

Data collection

Bruker APEX area-detector diffractometer	968 independent reflections
Radiation source: fine-focus sealed tube	956 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.020
φ and ω scans	θmax = 27.4°, θmin = 2.7°
Absorption correction: multi-scan (SADABS; Bruker, 2002)	h = −14→15
Tmin = 0.499, Tmax = 0.920	k = −12→12
2296 measured reflections	l = −9→8

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)] = 0.054	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.159	H atoms treated by a mixture of independent and constrained refinement
S = 1.19	w = 1/[σ^2(Fo^2) + (0.053P)^2 + 7.1943P] where P = (Fo^2 + 2Fc^2)/3
968 reflections	(Δ/σ)max = 0.001
113 parameters	Δρmax = 0.54 e Å^−3
14 restraints	Δρmin = −0.50 e Å^−3

Special details

Refinement. A dimensionless value, 2µ*r (r = equivalent radius of crystal) of 0.23, was used in the absorption correction step.

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

	x	y	z	Uiso*/Ueq	Occ. (<1)
Co1	0.5000	0.5000	0.5000	0.0214 (3)
O1	0.8314 (3)	0.6134 (4)	0.6609 (5)	0.048 (1)
O2	1.3222 (5)	0.5756 (7)	0.9709 (9)	0.038 (2)	0.50
O1W	0.6265 (3)	0.6455 (4)	0.5021 (6)	0.055 (1)
O2W	0.4893 (5)	0.5000	0.2226 (7)	0.065 (2)
N1	1.1453 (5)	0.6558 (8)	0.888 (1)	0.035 (2)	0.50
C1	1.0373 (7)	0.640 (1)	0.8183 (9)	0.030 (2)	0.50
C2	0.9997 (6)	0.513 (1)	0.7604 (9)	0.030 (2)	0.50
C3	1.0756 (7)	0.404 (1)	0.776 (1)	0.033 (2)	0.50
C4	1.1858 (7)	0.420 (1)	0.847 (1)	0.034 (2)	0.50
C5	1.2225 (8)	0.5505 (9)	0.904 (1)	0.030 (2)	0.50
C6	0.8778 (5)	0.5000	0.6882 (8)	0.029 (1)
H2O	1.3299	0.6615	0.9859	0.045*	0.50
H1W1	0.688 (2)	0.625 (4)	0.559 (5)	0.03 (1)*
H1W2	0.632 (4)	0.723 (3)	0.454 (6)	0.04 (2)*
H2W1	0.426 (3)	0.5000	0.164 (8)	0.04 (2)*
H2W2	0.545 (4)	0.5000	0.153 (7)	0.08 (3)*
H1	0.9882	0.7152	0.8096	0.037*	0.50
H3	1.0519	0.3180	0.7379	0.040*	0.50
H4	1.2352	0.3451	0.8563	0.041*	0.50

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Co1	0.0131 (5)	0.0250 (6)	0.0258 (6)	0.000	−0.0039 (4)	0.000
O1	0.044 (2)	0.034 (2)	0.066 (3)	0.002 (2)	−0.024 (2)	0.007 (2)
O2	0.024 (3)	0.047 (4)	0.042 (4)	0.002 (3)	−0.009 (3)	−0.004 (3)
O1W	0.029 (2)	0.042 (2)	0.093 (3)	−0.012 (2)	−0.025 (2)	0.030 (2)
O2W	0.032 (3)	0.133 (6)	0.029 (3)	0.000	−0.007 (2)	0.000
N1	0.028 (4)	0.032 (4)	0.043 (5)	0.002 (3)	−0.016 (3)	0.000 (4)
C1	0.025 (5)	0.032 (5)	0.033 (5)	0.003 (4)	−0.010 (4)	0.001 (4)
C2	0.023 (3)	0.041 (6)	0.025 (3)	0.013 (7)	−0.004 (2)	0.002 (6)
C3	0.034 (6)	0.033 (6)	0.033 (5)	0.009 (5)	−0.001 (4)	−0.007 (4)
C4	0.033 (6)	0.026 (6)	0.043 (7)	0.005 (4)	−0.003 (5)	−0.005 (5)
C5	0.027 (5)	0.034 (5)	0.029 (5)	0.009 (3)	−0.005 (4)	0.003 (3)
C6	0.030 (3)	0.031 (3)	0.027 (3)	0.000	−0.008 (2)	0.000

Geometric parameters (Å, º)

Co1—O1W	2.042 (3)	C3—C4	1.385 (9)
Co1—O1W^i	2.042 (3)	C4—C5	1.408 (8)
Co1—O1W^ii	2.042 (3)	C6—O1^iii	1.245 (4)
Co1—O1W^iii	2.042 (3)	C6—C2^iii	1.510 (9)
Co1—O2W	2.113 (5)	O2—H2O	0.85
Co1—O2W^ii	2.113 (5)	O1W—H1W1	0.85 (1)
O1—C6	1.245 (4)	O1W—H1W2	0.84 (1)
O2—C5	1.28 (1)	O2W—H2W1	0.85 (1)
N1—C1	1.358 (9)	O2W—H2W2	0.85 (1)
N1—C5	1.366 (8)	C1—H1	0.93
C1—C2	1.383 (9)	C3—H3	0.93
C2—C3	1.381 (9)	C4—H4	0.93
C2—C6	1.510 (9)
O1W^ii—Co1—O1W	180.0	C3—C4—C5	119.3 (9)
O1W^ii—Co1—O1W^i	88.1 (2)	O2—C5—N1	118.6 (8)
O1W—Co1—O1W^i	91.9 (2)	O2—C5—C4	124.1 (7)
O1W^ii—Co1—O1W^iii	91.9 (2)	N1—C5—C4	117.3 (8)
O1W—Co1—O1W^iii	88.1 (2)	O1^iii—C6—O1	125.2 (6)
O1W^i—Co1—O1W^iii	180	O1^iii—C6—C2	122.1 (6)
O1W^ii—Co1—O2W^ii	91.9 (2)	O1—C6—C2	112.6 (6)
O1W—Co1—O2W^ii	88.2 (2)	O1^iii—C6—C2^iii	112.6 (6)
O1W^i—Co1—O2W^ii	91.9 (2)	O1—C6—C2^iii	122.1 (6)
O1W^iii—Co1—O2W^ii	88.2 (2)	Co1—O1W—H1W1	116 (3)
O1W^ii—Co1—O2W	88.2 (2)	Co1—O1W—H1W2	133 (3)
O1W—Co1—O2W	91.9 (2)	H1W1—O1W—H1W2	111 (2)
O1W^i—Co1—O2W	88.2 (2)	Co1—O2W—H2W1	123 (5)
O1W^iii—Co1—O2W	91.9 (2)	Co1—O2W—H2W2	127 (5)
O2W^ii—Co1—O2W	180	H2W1—O2W—H2W2	110 (2)
C1—N1—C5	123.2 (9)	N1—C1—H1	119.8
N1—C1—C2	120.4 (8)	C2—C1—H1	119.8
C3—C2—C1	117.7 (8)	C2—C3—H3	119.0
C3—C2—C6	123.9 (9)	C4—C3—H3	119.0
C1—C2—C6	118.4 (9)	C3—C4—H4	120.3
C2—C3—C4	122.0 (9)	C5—C4—H4	120.3
C5—N1—C1—C2	0.1 (3)	C3—C4—C5—O2	−179.9 (8)
N1—C1—C2—C3	0.1 (3)	C3—C4—C5—N1	0.4 (8)
N1—C1—C2—C6	178.6 (6)	C3—C2—C6—O1^iii	10.6 (9)
C1—C2—C3—C4	0.0 (6)	C1—C2—C6—O1^iii	−167.8 (5)
C6—C2—C3—C4	−178.5 (7)	C3—C2—C6—O1	−169.5 (6)
C2—C3—C4—C5	−0.2 (8)	C1—C2—C6—O1	12.0 (7)
C1—N1—C5—O2	179.9 (7)	C3—C2—C6—C2^iii	10.6 (5)
C1—N1—C5—C4	−0.4 (6)	C1—C2—C6—C2^iii	−167.9 (4)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1W1···O1	0.85 (1)	1.83 (2)	2.659 (4)	168 (4)
O1W—H1W2···O1^iv	0.84 (1)	1.87 (1)	2.710 (5)	171 (5)
O2W—H2W1···O2^v	0.85 (1)	2.02 (3)	2.791 (8)	151 (4)
O2W—H2W1···O2^v	0.85 (1)	2.02 (3)	2.791 (8)	151 (4)
O2W—H2W2···O2^vi	0.85 (1)	1.97 (1)	2.769 (9)	157 (2)
O2W—H2W2···O2^vii	0.85 (1)	1.97 (1)	2.769 (9)	157 (2)
O2—H2O···N1^viii	0.85	2.04	2.86 (1)	159

Symmetry codes: (iv) −x+3/2, −y+3/2, −z+1; (v) x−1, y, z−1; (vi) −x+2, −y+1, −z+1; (vii) −x+2, y, −z+1; (viii) −x+5/2, −y+3/2, −z+2.