Hexa­aqua­nickel(II) bis­[(4-oxo-4H-pyridin-1-yl)­acetate] dihydrate

The title complex, [Ni(H₂O)₆](C₇H₆NO₃)₂·2H₂O, was synth­esized by the reaction of Ni(CH₃COO)₂·4H₂O and (4-oxo-4H-pyrindin-1-yl)­acetic acid in an aqueous solution. The nickel^II ion, which lies on a center of symmetry, is coordinated by six water mol­ecules to form an octahedron [Ni-O = 2.047 (1)-2.057 (1) Å]. A three-dimensional supramolecular framework is formed via hydrogen bonds between the anions and cations.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.029
• wR factor = 0.078
• Data-to-parameter ratio = 14.5

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  Ni1    -   O3W     ..       7.94 su
PLAT720_ALERT_4_C Number of Unusual/Non-Standard Label(s) ........          8

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

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 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
   1 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: RAPID-AUTO (Rigaku Corporation, 1998); cell refinement: RAPID-AUTO; data reduction: CrystalStructure (Rigaku/MSC and Rigaku Corporation, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97.

'Hexaaquanickel(II) bis[(4-oxo-4H-pyridin-1-yl)acetate] dihydrate'

Crystal data

[Ni(H2O)6](C7H6NO3)2·2H2O	F(000) = 532
Mr = 507.07	Dx = 1.585 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 6398 reflections
a = 12.387 (3) Å	θ = 3.6–27.4°
b = 12.816 (3) Å	µ = 0.99 mm^−1
c = 6.766 (1) Å	T = 293 K
β = 98.42 (3)°	Prism, green
V = 1062.6 (4) Å^3	0.36 × 0.25 × 0.18 mm
Z = 2

Data collection

Rigaku RAXIS-RAPID diffractometer	2423 independent reflections
Radiation source: fine-focus sealed tube	2237 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.027
Detector resolution: 10 pixels mm^-1	θmax = 27.5°, θmin = 3.2°
ω scans	h = −16→16
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	k = −16→16
Tmin = 0.718, Tmax = 0.842	l = −8→8
10195 measured reflections

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)] = 0.029	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.078	w = 1/[σ^2(Fo^2) + (0.0539P)^2 + 0.226P] where P = (Fo^2 + 2Fc^2)/3
S = 1.04	(Δ/σ)max < 0.001
2423 reflections	Δρmax = 0.35 e Å^−3
167 parameters	Δρmin = −0.77 e Å^−3
12 restraints	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.37 (1)

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
Ni1	0.0000	0.5000	0.0000	0.0216 (1)
O1	0.25666 (8)	0.79125 (8)	0.5949 (2)	0.0325 (2)
O2	0.10136 (8)	0.69862 (8)	0.5417 (2)	0.0306 (2)
O3	0.71588 (9)	0.61907 (9)	0.6729 (2)	0.0400 (3)
O1W	−0.02773 (9)	0.56660 (9)	0.2646 (2)	0.0361 (3)
H1W1	−0.0878 (9)	0.597 (2)	0.269 (3)	0.054*
H1W2	0.023 (1)	0.600 (2)	0.338 (3)	0.054*
O2W	0.16549 (9)	0.51745 (9)	0.0696 (2)	0.0337 (3)
H2W1	0.196 (2)	0.5762 (8)	0.086 (3)	0.051*
H2W2	0.204 (2)	0.472 (1)	0.136 (3)	0.051*
O3W	0.01496 (8)	0.35815 (8)	0.1413 (2)	0.0293 (2)
H3W1	−0.008 (2)	0.362 (2)	0.253 (2)	0.044*
H3W2	−0.021 (1)	0.311 (1)	0.070 (2)	0.044*
O4W	0.2171 (1)	0.1663 (1)	0.1937 (2)	0.0555 (4)
H4W1	0.221 (2)	0.155 (2)	0.070 (2)	0.083*
H4W2	0.223 (2)	0.2316 (9)	0.214 (4)	0.083*
N1	0.3835 (1)	0.61411 (9)	0.6404 (2)	0.0272 (3)
C1	0.2036 (1)	0.7086 (1)	0.5826 (2)	0.0234 (3)
C2	0.2642 (1)	0.6049 (1)	0.6221 (2)	0.0298 (3)
H2A	0.2455	0.5749	0.7443	0.036*
H2B	0.2390	0.5572	0.5139	0.036*
C3	0.4301 (1)	0.6318 (1)	0.4744 (2)	0.0314 (3)
H3	0.3855	0.6415	0.3527	0.038*
C4	0.5401 (1)	0.6357 (1)	0.4808 (2)	0.0318 (3)
H4	0.5692	0.6482	0.3639	0.038*
C5	0.6121 (1)	0.6208 (1)	0.6643 (2)	0.0290 (3)
C6	0.5594 (1)	0.6080 (1)	0.8362 (2)	0.0346 (3)
H6	0.6013	0.6016	0.9615	0.041*
C7	0.4486 (1)	0.6048 (1)	0.8195 (2)	0.0333 (3)
H7	0.4164	0.5960	0.9342	0.040*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Ni1	0.0204 (2)	0.0195 (2)	0.0243 (2)	−0.00179 (7)	0.00113 (9)	−0.00067 (7)
O1	0.0278 (5)	0.0235 (5)	0.0446 (6)	0.0010 (4)	−0.0003 (4)	−0.0021 (4)
O2	0.0229 (5)	0.0306 (5)	0.0376 (6)	0.0022 (4)	0.0020 (4)	0.0008 (4)
O3	0.0250 (5)	0.0441 (6)	0.0499 (7)	0.0040 (4)	0.0018 (5)	0.0085 (5)
O1W	0.0319 (6)	0.0420 (6)	0.0337 (6)	0.0013 (5)	0.0028 (4)	−0.0134 (5)
O2W	0.0233 (5)	0.0260 (5)	0.0487 (7)	−0.0036 (4)	−0.0050 (5)	0.0063 (4)
O3W	0.0317 (5)	0.0250 (5)	0.0312 (5)	−0.0031 (4)	0.0043 (4)	0.0017 (4)
O4W	0.0575 (8)	0.0474 (8)	0.0682 (9)	−0.0129 (6)	0.0312 (7)	−0.0079 (6)
N1	0.0253 (6)	0.0242 (6)	0.0322 (6)	0.0059 (4)	0.0040 (5)	0.0032 (4)
C1	0.0248 (6)	0.0240 (6)	0.0213 (6)	0.0035 (5)	0.0032 (5)	−0.0007 (4)
C2	0.0257 (7)	0.0234 (6)	0.0406 (8)	0.0024 (5)	0.0062 (6)	0.0024 (5)
C3	0.0313 (7)	0.0330 (7)	0.0289 (7)	0.0049 (6)	0.0010 (6)	0.0063 (5)
C4	0.0307 (7)	0.0338 (7)	0.0313 (7)	0.0038 (6)	0.0056 (6)	0.0073 (6)
C5	0.0271 (7)	0.0218 (6)	0.0373 (8)	0.0027 (5)	0.0020 (6)	0.0021 (5)
C6	0.0346 (8)	0.0398 (8)	0.0275 (7)	0.0049 (6)	−0.0016 (6)	0.0004 (6)
C7	0.0361 (8)	0.0364 (7)	0.0279 (7)	0.0070 (6)	0.0066 (6)	0.0018 (6)

Geometric parameters (Å, º)

Ni1—O2W	2.047 (1)	O4W—H4W2	0.850 (9)
Ni1—O2W^i	2.047 (1)	N1—C3	1.355 (2)
Ni1—O3W	2.050 (1)	N1—C7	1.358 (2)
Ni1—O3W^i	2.050 (1)	N1—C2	1.470 (2)
Ni1—O1W^i	2.057 (1)	C1—C2	1.530 (2)
Ni1—O1W	2.057 (1)	C2—H2A	0.9700
O1—C1	1.243 (2)	C2—H2B	0.9700
O2—C1	1.263 (2)	C3—C4	1.358 (2)
O3—C5	1.278 (2)	C3—H3	0.9300
O1W—H1W1	0.841 (9)	C4—C5	1.431 (2)
O1W—H1W2	0.856 (19)	C4—H4	0.9300
O2W—H2W1	0.843 (9)	C5—C6	1.425 (2)
O2W—H2W2	0.840 (19)	C6—C7	1.362 (2)
O3W—H3W1	0.847 (9)	C6—H6	0.9300
O3W—H3W2	0.850 (9)	C7—H7	0.9300
O4W—H4W1	0.857 (9)
O2W—Ni1—O2W^i	180.00 (2)	C3—N1—C2	119.2 (1)
O2W—Ni1—O3W	88.31 (4)	C7—N1—C2	121.7 (1)
O2W^i—Ni1—O3W	91.69 (4)	O1—C1—O2	127.2 (1)
O2W—Ni1—O3W^i	91.69 (4)	O1—C1—C2	119.2 (1)
O2W^i—Ni1—O3W^i	88.31 (4)	O2—C1—C2	113.6 (1)
O3W—Ni1—O3W^i	180.00 (3)	N1—C2—C1	114.0 (1)
O2W—Ni1—O1W^i	87.50 (6)	N1—C2—H2A	108.8
O2W^i—Ni1—O1W^i	92.50 (5)	C1—C2—H2A	108.8
O3W—Ni1—O1W^i	91.29 (5)	N1—C2—H2B	108.8
O3W^i—Ni1—O1W^i	88.71 (5)	C1—C2—H2B	108.8
O2W—Ni1—O1W	92.50 (6)	H2A—C2—H2B	107.6
O2W^i—Ni1—O1W	87.50 (6)	N1—C3—C4	121.8 (1)
O3W—Ni1—O1W	88.71 (5)	N1—C3—H3	119.1
O3W^i—Ni1—O1W	91.29 (5)	C4—C3—H3	119.1
O1W^i—Ni1—O1W	180.00 (6)	C3—C4—C5	121.2 (1)
Ni1—O1W—H1W1	118 (1)	C3—C4—H4	119.4
Ni1—O1W—H1W2	121 (1)	C5—C4—H4	119.4
H1W1—O1W—H1W2	109 (1)	O3—C5—C6	122.6 (1)
Ni1—O2W—H2W1	123 (1)	O3—C5—C4	122.5 (1)
Ni1—O2W—H2W2	121 (1)	C6—C5—C4	115.0 (1)
H2W1—O2W—H2W2	110 (1)	C7—C6—C5	120.8 (1)
Ni1—O3W—H3W1	111 (1)	C7—C6—H6	119.6
Ni1—O3W—H3W2	111 (1)	C5—C6—H6	119.6
H3W1—O3W—H3W2	109 (1)	N1—C7—C6	122.1 (1)
H4W1—O4W—H4W2	108 (2)	N1—C7—H7	119.0
C3—N1—C7	119.0 (1)	C6—C7—H7	119.0
C3—N1—C2—C1	−73.2 (2)	C3—C4—C5—O3	176.6 (1)
C7—N1—C2—C1	107.2 (2)	C3—C4—C5—C6	−3.4 (2)
O1—C1—C2—N1	−9.2 (2)	O3—C5—C6—C7	−176.6 (1)
O2—C1—C2—N1	171.4 (1)	C4—C5—C6—C7	3.4 (2)
C7—N1—C3—C4	3.1 (2)	C3—N1—C7—C6	−3.1 (2)
C2—N1—C3—C4	−176.6 (1)	C2—N1—C7—C6	176.6 (1)
N1—C3—C4—C5	0.2 (2)	C5—C6—C7—N1	−0.3 (2)

Symmetry code: (i) −x, −y+1, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1W2···O2	0.86 (2)	2.02 (1)	2.839 (2)	162 (2)
O1W—H1W1···O4W^ii	0.84 (1)	1.88 (1)	2.722 (2)	174 (2)
O2W—H2W1···O1^iii	0.84 (1)	1.85 (1)	2.694 (2)	174 (2)
O2W—H2W2···O3^iv	0.84 (2)	1.90 (1)	2.739 (2)	170 (2)
O3W—H3W1···O2^v	0.85 (1)	2.08 (1)	2.848 (2)	150 (2)
O3W—H3W2···O2^vi	0.85 (1)	1.86 (1)	2.696 (2)	170 (2)
O4W—H4W1···O3^vii	0.86 (1)	1.98 (1)	2.795 (2)	159 (3)
O4W—H4W2···O3^iv	0.85 (1)	2.16 (1)	2.975 (2)	162 (3)

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