Hexa­aqua­nickel(II) 3-carboxy-4-hydroxy­benzene­sulfonate tetrahydrate

In the title compound, [Ni(H₂O)₆]L₂·4H₂O, where HL = 3-carboxy-4-hydroxy­benzene­sulfonic acid (C₇H₆O₆S), each Ni^II cation lies on an inversion center and is octahedrally coordinated by six water mol­ecules. The L^- anions do not coordinate to nickel, but act as counter-anions. The crystal structure is composed of alternating layers of [Ni(H₂O)₆]²⁺ cations and sulfonate anions. The [Ni(H₂O)₆]²⁺ cations, water mol­ecules and L^- anions are connected through a complex pattern of hydrogen-bonding interactions.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.038
• wR factor = 0.101
• Data-to-parameter ratio = 12.5

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S1. Comment

The crystal structures of five transition metal (Mn, Co, Ni, Cu and Zn) 3-carboxy-4-hydroxybenzenesulfonates have been determined. The structures of the manganese (Ma et al., 2003a) and cobalt compound (Ma et al., 2003b) have been reported in the preceding papers. The crystal structure of the nickel compound, (I), is presented here. The crystal structures of the other two related compounds are reported in the following papers.

The Ni^II atom is located on an inversion center, and all other atoms are in general positions. Selected bond lengths and angles are given in Table 1. Fig. 1 shows the asymmetric unit, together with the complete coordination environment of the Ni^II cation. Compound (I) is isostructural with the cobalt compound (Ma et al., 2003b). The N—O distances range from 2.030 (2) to 2.057 (2) Å. The average Ni—O distance of 2.047 Å is similar to the values in other nickel compounds (Gunderman et al., 1997; Kosnic et al., 1992).

The alternating layers of [Ni(H₂O)₆]²⁺ cations and sulfonate anions in (I) are shown in Fig.2. Selected hydrogen-bond parameters are listed in Table 2.

S2. Experimental

A mixture of 3-carboxy-4-hydroxybenzenesulfonic acid (0.44 g, 2 mmol) and NiCO₃ (0.12 g, 1 mmol) in water (10 ml) was stirred at room temperature for 30 min. Green crystals of compound (I) were obtained after leaving the solution to stand at room temperature for several days. Analysis calculated for C₁₄H₃₀NiO₂₂S₂: C 24.98, H 4.49%; found: C 24.82, H 4.47%.

S3. Refinement

All H atoms on C atoms were positioned geometrically and refined as riding atoms, with C—H = 0.93 Å and U_iso(H) = 1.2U_eq(C). The H atoms of the carboxyl group and hydroxyl group were also positioned geometrically and refined as riding atoms, with O—H = 0.82 Å and U_iso(H) = 1.5U_eq(O). The water H atoms were located in a difference Fourier map and refined with U_iso(H) = 1.5U_eq(O).

Computing details

Data collection: XSCANS (Siemens, 1994); cell refinement: XSCANS; data reduction: XSCANS; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL-Plus (Sheldrick, 1990); software used to prepare material for publication: SHELXL97.

Figures

	Fig. 1. View of the asymmetric unit, expanded to show the complete coordination of Ni^II, with the atomic numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. View of the alternating layers of cations and anions, along the a axis.

(I)

Crystal data

[Ni(H2O)6](C7H5O6S)2·4H2O	Z = 1
Mr = 673.21	F(000) = 350
Triclinic, P1	Dx = 1.686 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 6.5380 (9) Å	Cell parameters from 20 reflections
b = 7.2199 (10) Å	θ = 5.9–9.7°
c = 14.534 (4) Å	µ = 0.99 mm^−1
α = 92.931 (16)°	T = 293 K
β = 96.494 (16)°	Block, green
γ = 102.727 (12)°	0.36 × 0.24 × 0.15 mm
V = 662.9 (2) Å^3

Data collection

Siemens P4 diffractometer	2145 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.026
Graphite monochromator	θmax = 26.0°, θmin = 2.8°
ω scans	h = −1→8
Absorption correction: ψ scan (North et al., 1968)	k = −8→8
Tmin = 0.687, Tmax = 0.863	l = −17→17
3424 measured reflections	3 standard reflections every 97 reflections
2599 independent reflections	intensity decay: none

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)] = 0.038	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.101	H atoms treated by a mixture of independent and constrained refinement
S = 1.09	w = 1/[σ^2(Fo^2) + (0.0506P)^2 + 0.1374P] where P = (Fo^2 + 2Fc^2)/3
2599 reflections	(Δ/σ)max < 0.001
208 parameters	Δρmax = 0.58 e Å^−3
10 restraints	Δρmin = −0.47 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.

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

	x	y	z	Uiso*/Ueq
C1	0.3984 (4)	0.1628 (3)	0.35573 (17)	0.0278 (5)
C2	0.3124 (4)	0.1629 (3)	0.43782 (17)	0.0279 (5)
H2	0.1687	0.1125	0.4380	0.033*
C3	0.4391 (4)	0.2378 (3)	0.52047 (17)	0.0273 (5)
C4	0.6558 (4)	0.3165 (4)	0.51950 (18)	0.0295 (6)
C5	0.7410 (4)	0.3130 (4)	0.43618 (19)	0.0355 (6)
H5	0.8848	0.3617	0.4355	0.043*
C6	0.6144 (4)	0.2382 (4)	0.35461 (19)	0.0343 (6)
H6	0.6722	0.2378	0.2990	0.041*
C7	0.3473 (4)	0.2389 (4)	0.60864 (18)	0.0316 (6)
O1	0.0942 (4)	0.2087 (3)	0.23422 (16)	0.0517 (6)
O2	0.3624 (3)	0.0621 (3)	0.17979 (14)	0.0482 (6)
O3	0.1033 (3)	−0.1100 (3)	0.26806 (13)	0.0381 (5)
O4	0.1434 (3)	0.1633 (3)	0.59849 (14)	0.0474 (6)
H4	0.0996	0.1669	0.6491	0.071*
O5	0.4502 (3)	0.3030 (3)	0.68376 (13)	0.0438 (5)
O6	0.7848 (3)	0.3981 (3)	0.59650 (14)	0.0432 (5)
H6A	0.7175	0.3916	0.6410	0.065*
OW1	0.7004 (4)	0.3312 (3)	0.97347 (16)	0.0486 (6)
OW2	0.7265 (3)	0.7363 (3)	0.97940 (14)	0.0395 (5)
OW3	0.6189 (3)	0.5222 (3)	1.13815 (13)	0.0406 (5)
OW4	0.7348 (3)	0.0508 (3)	0.09873 (15)	0.0427 (5)
OW5	0.0476 (4)	0.5520 (3)	0.16465 (15)	0.0440 (5)
S1	0.23022 (10)	0.07503 (9)	0.25133 (4)	0.02897 (18)
Ni1	0.5000	0.5000	1.0000	0.02897 (16)
H1A	0.750 (5)	0.253 (4)	1.0117 (19)	0.043*
H1B	0.803 (4)	0.374 (4)	0.940 (2)	0.043*
H2A	0.721 (5)	0.787 (4)	0.9240 (15)	0.043*
H2B	0.743 (5)	0.835 (3)	1.0213 (18)	0.043*
H3A	0.589 (5)	0.595 (4)	1.1831 (18)	0.043*
H3B	0.756 (3)	0.523 (4)	1.153 (2)	0.043*
H4A	0.834 (4)	0.097 (4)	0.1467 (17)	0.043*
H4B	0.610 (4)	0.028 (4)	0.122 (2)	0.043*
H5A	0.086 (5)	0.463 (4)	0.196 (2)	0.043*
H5B	0.093 (5)	0.658 (3)	0.2035 (19)	0.043*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0303 (13)	0.0270 (12)	0.0263 (12)	0.0074 (10)	0.0026 (10)	0.0035 (10)
C2	0.0257 (12)	0.0296 (13)	0.0290 (13)	0.0062 (10)	0.0054 (10)	0.0034 (10)
C3	0.0282 (13)	0.0272 (13)	0.0287 (13)	0.0087 (10)	0.0072 (10)	0.0035 (10)
C4	0.0284 (13)	0.0279 (13)	0.0313 (13)	0.0058 (10)	0.0012 (11)	0.0012 (10)
C5	0.0248 (13)	0.0400 (15)	0.0393 (15)	0.0005 (11)	0.0073 (11)	0.0038 (12)
C6	0.0333 (14)	0.0377 (15)	0.0330 (14)	0.0044 (12)	0.0138 (12)	0.0063 (11)
C7	0.0334 (14)	0.0327 (14)	0.0302 (14)	0.0099 (11)	0.0064 (11)	0.0020 (11)
O1	0.0559 (14)	0.0447 (12)	0.0537 (13)	0.0218 (11)	−0.0148 (11)	−0.0005 (10)
O2	0.0407 (12)	0.0726 (15)	0.0281 (10)	0.0032 (11)	0.0123 (9)	0.0001 (10)
O3	0.0450 (11)	0.0347 (10)	0.0304 (10)	−0.0024 (9)	0.0118 (9)	−0.0015 (8)
O4	0.0347 (11)	0.0699 (15)	0.0324 (11)	−0.0017 (10)	0.0144 (9)	−0.0077 (10)
O5	0.0399 (11)	0.0624 (14)	0.0275 (10)	0.0110 (10)	0.0031 (9)	−0.0053 (9)
O6	0.0315 (10)	0.0584 (13)	0.0343 (11)	0.0037 (9)	−0.0023 (8)	−0.0029 (9)
OW1	0.0572 (14)	0.0538 (14)	0.0489 (13)	0.0319 (12)	0.0238 (11)	0.0145 (11)
OW2	0.0507 (12)	0.0374 (11)	0.0297 (10)	0.0062 (10)	0.0090 (9)	0.0049 (8)
OW3	0.0433 (12)	0.0544 (13)	0.0261 (10)	0.0160 (10)	0.0047 (9)	−0.0010 (9)
OW4	0.0349 (11)	0.0509 (13)	0.0411 (11)	0.0097 (10)	0.0022 (9)	−0.0018 (10)
OW5	0.0520 (13)	0.0351 (11)	0.0455 (12)	0.0135 (10)	0.0037 (10)	−0.0023 (9)
S1	0.0312 (3)	0.0316 (3)	0.0238 (3)	0.0055 (3)	0.0045 (3)	0.0042 (2)
Ni1	0.0345 (3)	0.0309 (3)	0.0238 (2)	0.0106 (2)	0.00686 (19)	0.00235 (18)

Geometric parameters (Å, º)

C1—C2	1.375 (4)	O6—H6A	0.820
C1—C6	1.399 (4)	OW1—Ni1	2.030 (2)
C1—S1	1.769 (3)	OW1—H1A	0.898 (18)
C2—C3	1.390 (4)	OW1—H1B	0.883 (18)
C2—H2	0.930	OW2—Ni1	2.057 (2)
C3—C4	1.407 (4)	OW2—H2A	0.902 (18)
C3—C7	1.476 (3)	OW2—H2B	0.893 (18)
C4—O6	1.346 (3)	OW3—Ni1	2.054 (2)
C4—C5	1.390 (4)	OW3—H3A	0.882 (18)
C5—C6	1.378 (4)	OW3—H3B	0.894 (18)
C5—H5	0.930	OW4—H4A	0.894 (18)
C6—H6	0.930	OW4—H4B	0.902 (18)
C7—O5	1.226 (3)	OW5—H5A	0.872 (18)
C7—O4	1.313 (3)	OW5—H5B	0.902 (18)
O1—S1	1.462 (2)	Ni1—OW1^i	2.030 (2)
O2—S1	1.437 (2)	Ni1—OW3^i	2.054 (2)
O3—S1	1.4569 (19)	Ni1—OW2^i	2.057 (2)
O4—H4	0.820
C2—C1—C6	120.3 (2)	H2A—OW2—H2B	105 (3)
C2—C1—S1	119.0 (2)	Ni1—OW3—H3A	127 (2)
C6—C1—S1	120.7 (2)	Ni1—OW3—H3B	118 (2)
C1—C2—C3	120.4 (2)	H3A—OW3—H3B	105 (3)
C1—C2—H2	119.8	H4A—OW4—H4B	106 (3)
C3—C2—H2	119.8	H5A—OW5—H5B	104 (3)
C2—C3—C4	119.6 (2)	O2—S1—O3	112.45 (13)
C2—C3—C7	120.5 (2)	O2—S1—O1	113.34 (15)
C4—C3—C7	119.9 (2)	O3—S1—O1	109.89 (14)
O6—C4—C5	118.2 (2)	O2—S1—C1	107.45 (12)
O6—C4—C3	122.4 (2)	O3—S1—C1	106.75 (12)
C5—C4—C3	119.4 (2)	O1—S1—C1	106.54 (12)
C6—C5—C4	120.6 (2)	OW1—Ni1—OW1^i	180.0
C6—C5—H5	119.7	OW1—Ni1—OW3^i	91.04 (9)
C4—C5—H5	119.7	OW1^i—Ni1—OW3^i	88.96 (9)
C5—C6—C1	119.7 (3)	OW1—Ni1—OW3	88.96 (9)
C5—C6—H6	120.1	OW1^i—Ni1—OW3	91.04 (9)
C1—C6—H6	120.1	OW3^i—Ni1—OW3	180.0
O5—C7—O4	123.3 (3)	OW1—Ni1—OW2^i	90.08 (10)
O5—C7—C3	123.7 (3)	OW1^i—Ni1—OW2^i	89.92 (10)
O4—C7—C3	113.0 (2)	OW3^i—Ni1—OW2^i	90.05 (9)
C7—O4—H4	109.5	OW3—Ni1—OW2^i	89.95 (9)
C4—O6—H6A	109.5	OW1—Ni1—OW2	89.92 (10)
Ni1—OW1—H1A	127 (2)	OW1^i—Ni1—OW2	90.08 (10)
Ni1—OW1—H1B	118 (2)	OW3^i—Ni1—OW2	89.95 (9)
H1A—OW1—H1B	106 (3)	OW3—Ni1—OW2	90.05 (9)
Ni1—OW2—H2A	120 (2)	OW2^i—Ni1—OW2	180.0
Ni1—OW2—H2B	115 (2)
C6—C1—C2—C3	0.0 (4)	S1—C1—C6—C5	177.3 (2)
S1—C1—C2—C3	−177.46 (19)	C2—C3—C7—O5	−179.9 (3)
C1—C2—C3—C4	1.0 (4)	C4—C3—C7—O5	−1.2 (4)
C1—C2—C3—C7	179.7 (2)	C2—C3—C7—O4	0.3 (4)
C2—C3—C4—O6	177.3 (2)	C4—C3—C7—O4	179.1 (2)
C7—C3—C4—O6	−1.5 (4)	C2—C1—S1—O2	−170.8 (2)
C2—C3—C4—C5	−1.9 (4)	C6—C1—S1—O2	11.8 (3)
C7—C3—C4—C5	179.4 (2)	C2—C1—S1—O3	−49.9 (2)
O6—C4—C5—C6	−177.4 (2)	C6—C1—S1—O3	132.6 (2)
C3—C4—C5—C6	1.8 (4)	C2—C1—S1—O1	67.4 (2)
C4—C5—C6—C1	−0.8 (4)	C6—C1—S1—O1	−110.0 (2)
C2—C1—C6—C5	−0.1 (4)

Symmetry code: (i) −x+1, −y+1, −z+2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
OW1—H1A···OW4^ii	0.90 (2)	1.97 (2)	2.820 (3)	156 (3)
OW1—H1B···OW5^iii	0.88 (2)	1.93 (2)	2.786 (3)	162 (3)
OW2—H2A···O2^iii	0.90 (2)	2.00 (2)	2.867 (3)	161 (3)
OW2—H2B···OW4^iv	0.89 (2)	1.89 (2)	2.773 (3)	170 (3)
OW3—H3B···OW5^v	0.89 (2)	1.86 (2)	2.745 (3)	169 (3)
OW3—H3A···O5^i	0.88 (2)	2.10 (2)	2.946 (3)	161 (3)
OW4—H4B···O2	0.90 (2)	1.96 (2)	2.837 (3)	163 (3)
OW4—H4A···O1^vi	0.89 (2)	1.99 (2)	2.871 (3)	169 (3)
OW5—H5B···O3^vii	0.90 (2)	1.86 (2)	2.731 (3)	162 (3)
OW5—H5A···O1	0.87 (2)	1.96 (2)	2.789 (3)	160 (3)
O4—H4···O3^viii	0.82	1.88	2.650 (3)	155
O6—H6A···O5	0.82	1.91	2.631 (3)	146

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