catena-Poly[[[diaqua-iron(II)]-μ-pyridine-2,5-dicarboxyl-ato-[tetra-aqua-iron(II)]-μ-pyridine-2,5-dicarboxyl-ato] tetra-hydrate].

In the crystal structure of the title compound, {[Fe(2)(C(7)H(3)NO(4))(2)(H(2)O)(6)]·4H(2)O}(n), there are two types of coordination for the Fe(II) atoms. One Fe(II) atom is in a distorted octa-hedral N(2)O(4) environment, with two chelating rings from the pyridine-dicarboxyl-ate ligands and two O atoms from the water mol-ecules, while the other is in a distorted octa-hedral O(6) environment with two O atoms from the pyridine-dicarboxyl-ate ligands and four O atoms from the water mol-ecules. Both Fe(II) atoms lie on crystallographic centers of symmetry. The complex possesses an infinite chain structure running along the [101] direction. These chains are inter-connected by the uncoordinated water mol-ecules through O-H⋯O hydrogen bonds.

Related literature

For related literature, see: Hill (1998 ▶); Liang et al. (2001 ▶); Mitzi et al. (1995 ▶); Moler et al. (2001 ▶); Zeng et al. (2003 ▶); Xu et al. (2004 ▶).

Experimental

Crystal data

[Fe2(C7H3NO4)2(H2O)6]·4H2O

M = 622.06

Triclinic,

a = 7.098 (3) Å

b = 8.922 (3) Å

c = 9.720 (2) Å

α = 90.942 (6)°

β = 101.375 (6)°

γ = 108.112 (5)°

V = 571.6 (3) Å3

Z = 1

Mo Kα radiation

μ = 1.36 mm−1

T = 298 (2) K

0.21 × 0.20 × 0.18 mm

Data collection

Bruker SMART APEX CCD diffractometer

Absorption correction: multi-scan (; Sheldrick, 1996 ▶) T min = 0.763, T max = 0.792

2866 measured reflections

1989 independent reflections

1757 reflections with I > 2σ(I)

R int = 0.062

Refinement

R[F 2 > 2σ(F 2)] = 0.043

wR(F 2) = 0.124

S = 1.06

1989 reflections

166 parameters

H-atom parameters constrained

Δρmax = 0.65 e Å−3

Δρmin = −0.60 e Å−3

Data collection: SMART (Siemens, 1996 ▶); cell refinement: SAINT (Siemens, 1996 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXTL.

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808002043/is2270sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808002043/is2270Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

[Fe2(C7H3NO4)2(H2O)6]·4H2O	Z = 1
Mr = 622.06	F000 = 320
Triclinic, P1	Dx = 1.807 Mg m−3
Hall symbol: -P 1	Mo Kα radiation λ = 0.71073 Å
a = 7.098 (3) Å	Cell parameters from 714 reflections
b = 8.922 (3) Å	θ = 2.4–28.2º
c = 9.720 (2) Å	µ = 1.36 mm−1
α = 90.942 (6)º	T = 298 (2) K
β = 101.375 (6)º	Block, red
γ = 108.112 (5)º	0.21 × 0.20 × 0.18 mm
V = 571.6 (3) Å3

Bruker SMART APEX CCD diffractometer	1989 independent reflections
Radiation source: fine-focus sealed tube	1757 reflections with I > 2σ(I)
Monochromator: graphite	Rint = 0.062
T = 298(2) K	θmax = 25.0º
φ and ω scans	θmin = 2.1º
Absorption correction: multi-scan(SADABS; Sheldrick, 1996)	h = −8→6
Tmin = 0.763, Tmax = 0.792	k = −10→10
2866 measured reflections	l = −11→10

Refinement on F2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.043	H-atom parameters constrained
wR(F2) = 0.124	w = 1/[σ2(Fo2) + (0.081P)2 + 0.2244P] where P = (Fo2 + 2Fc2)/3
S = 1.06	(Δ/σ)max < 0.001
1989 reflections	Δρmax = 0.65 e Å−3
166 parameters	Δρmin = −0.60 e Å−3
Primary atom site location: structure-invariant direct methods	Extinction correction: none

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
Fe1	0.5000	0.5000	0.0000	0.0222 (2)
Fe2	1.0000	0.5000	0.5000	0.0258 (2)
C1	0.6446 (4)	0.3738 (3)	0.2523 (3)	0.0270 (6)
C2	0.4924 (4)	0.2309 (3)	0.1667 (3)	0.0275 (6)
C3	0.4514 (5)	0.0824 (3)	0.2147 (3)	0.0330 (7)
H3	0.5126	0.0679	0.3050	0.040*
C4	0.3189 (5)	−0.0438 (3)	0.1270 (3)	0.0331 (7)
H4	0.2889	−0.1449	0.1579	0.040*
C5	0.2302 (4)	−0.0216 (3)	−0.0065 (3)	0.0278 (6)
C6	0.2767 (4)	0.1328 (3)	−0.0474 (3)	0.0279 (6)
H6	0.2161	0.1496	−0.1372	0.033*
C7	0.0905 (4)	−0.1587 (4)	−0.1093 (3)	0.0318 (7)
N1	0.4039 (3)	0.2565 (3)	0.0369 (3)	0.0261 (5)
O1	0.8315 (4)	0.6187 (3)	0.5803 (3)	0.0448 (6)
H1A	0.7132	0.6145	0.5373	0.054*
H1B	0.9150	0.7017	0.6279	0.054*
O2	0.9411 (3)	0.3350 (3)	0.6494 (2)	0.0425 (6)
H2B	0.8576	0.2419	0.6286	0.051*
H2A	1.0460	0.3570	0.7156	0.051*
O3	0.7348 (3)	0.3533 (2)	0.3701 (2)	0.0352 (5)
O4	0.6748 (3)	0.5047 (2)	0.1970 (2)	0.0334 (5)
O5	0.2787 (3)	0.5429 (3)	0.0954 (2)	0.0361 (5)
H5A	0.1792	0.5354	0.0276	0.043*
H5B	0.2288	0.4806	0.1537	0.043*
O6	0.0097 (4)	−0.1287 (3)	−0.2262 (3)	0.0473 (6)
O7	0.0653 (4)	−0.2939 (3)	−0.0688 (3)	0.0430 (6)
O8	0.4663 (4)	0.2880 (4)	0.6019 (3)	0.0640 (8)
H8B	0.4601	0.3105	0.6859	0.077*
H8A	0.5871	0.3270	0.5904	0.077*
O9	0.1591 (7)	−0.0327 (5)	0.4428 (6)	0.1112 (15)
H9B	0.2489	0.0471	0.4912	0.133*
H9A	0.1463	0.0205	0.3718	0.133*

	U11	U22	U33	U12	U13	U23
Fe1	0.0226 (3)	0.0153 (3)	0.0243 (3)	0.0050 (2)	−0.0034 (2)	−0.0004 (2)
Fe2	0.0269 (4)	0.0200 (3)	0.0247 (3)	0.0056 (2)	−0.0043 (2)	−0.0003 (2)
C1	0.0253 (14)	0.0248 (14)	0.0301 (15)	0.0088 (12)	0.0027 (11)	−0.0011 (11)
C2	0.0261 (14)	0.0260 (14)	0.0284 (15)	0.0082 (12)	0.0021 (11)	−0.0013 (11)
C3	0.0369 (17)	0.0282 (15)	0.0302 (16)	0.0083 (13)	0.0019 (13)	0.0059 (12)
C4	0.0357 (16)	0.0215 (14)	0.0403 (17)	0.0090 (13)	0.0041 (13)	0.0059 (12)
C5	0.0251 (14)	0.0225 (14)	0.0355 (16)	0.0079 (12)	0.0054 (12)	0.0003 (12)
C6	0.0277 (15)	0.0226 (13)	0.0314 (15)	0.0088 (12)	0.0006 (12)	−0.0004 (11)
C7	0.0242 (14)	0.0258 (15)	0.0432 (18)	0.0083 (12)	0.0023 (13)	−0.0049 (13)
N1	0.0259 (12)	0.0187 (11)	0.0308 (13)	0.0071 (10)	−0.0003 (10)	0.0014 (9)
O1	0.0403 (13)	0.0383 (13)	0.0492 (14)	0.0153 (11)	−0.0089 (11)	−0.0151 (11)
O2	0.0407 (13)	0.0349 (12)	0.0411 (13)	0.0033 (10)	−0.0026 (10)	0.0113 (10)
O3	0.0366 (12)	0.0278 (11)	0.0308 (11)	0.0047 (9)	−0.0072 (9)	0.0010 (8)
O4	0.0367 (12)	0.0228 (10)	0.0314 (11)	0.0071 (9)	−0.0096 (9)	−0.0011 (8)
O5	0.0320 (11)	0.0320 (12)	0.0439 (13)	0.0104 (10)	0.0072 (10)	0.0046 (10)
O6	0.0572 (15)	0.0302 (12)	0.0434 (14)	0.0136 (11)	−0.0134 (11)	−0.0088 (10)
O7	0.0367 (13)	0.0198 (11)	0.0632 (16)	0.0040 (10)	−0.0020 (11)	−0.0008 (10)
O8	0.0469 (16)	0.075 (2)	0.066 (2)	0.0196 (16)	0.0038 (14)	0.0019 (16)
O9	0.116 (3)	0.054 (2)	0.163 (5)	0.019 (2)	0.041 (3)	0.000 (2)

Fe1—O4	2.058 (2)	C4—C5	1.372 (4)
Fe1—O4i	2.058 (2)	C4—H4	0.9300
Fe1—O5i	2.100 (2)	C5—C6	1.397 (4)
Fe1—O5	2.100 (2)	C5—C7	1.515 (4)
Fe1—N1	2.125 (2)	C6—N1	1.328 (4)
Fe1—N1i	2.125 (2)	C6—H6	0.9300
Fe2—O1	2.071 (2)	C7—O6	1.241 (4)
Fe2—O1ii	2.071 (2)	C7—O7	1.245 (4)
Fe2—O3ii	2.080 (2)	O1—H1A	0.8499
Fe2—O3	2.080 (2)	O1—H1B	0.8499
Fe2—O2	2.092 (2)	O2—H2B	0.8500
Fe2—O2ii	2.092 (2)	O2—H2A	0.8501
C1—O3	1.242 (3)	O5—H5A	0.8499
C1—O4	1.268 (4)	O5—H5B	0.8500
C1—C2	1.496 (4)	O8—H8B	0.8500
C2—N1	1.351 (4)	O8—H8A	0.8499
C2—C3	1.376 (4)	O9—H9B	0.8499
C3—C4	1.368 (4)	O9—H9A	0.8500
C3—H3	0.9300
O4—Fe1—O4i	180.00 (11)	N1—C2—C1	115.5 (2)
O4—Fe1—O5i	90.89 (9)	C3—C2—C1	122.3 (3)
O4i—Fe1—O5i	89.11 (9)	C4—C3—C2	118.8 (3)
O4—Fe1—O5	89.11 (9)	C4—C3—H3	120.6
O4i—Fe1—O5	90.89 (9)	C2—C3—H3	120.6
O5i—Fe1—O5	180.00 (6)	C3—C4—C5	120.2 (3)
O4—Fe1—N1	79.00 (8)	C3—C4—H4	119.9
O4i—Fe1—N1	101.00 (8)	C5—C4—H4	119.9
O5i—Fe1—N1	88.20 (9)	C4—C5—C6	117.9 (3)
O5—Fe1—N1	91.80 (9)	C4—C5—C7	121.9 (3)
O4—Fe1—N1i	101.00 (8)	C6—C5—C7	120.2 (3)
O4i—Fe1—N1i	79.00 (8)	N1—C6—C5	122.5 (3)
O5i—Fe1—N1i	91.80 (9)	N1—C6—H6	118.7
O5—Fe1—N1i	88.20 (9)	C5—C6—H6	118.7
N1—Fe1—N1i	180.0	O6—C7—O7	125.1 (3)
O1—Fe2—O1ii	180.00 (12)	O6—C7—C5	118.1 (3)
O1—Fe2—O3ii	90.59 (9)	O7—C7—C5	116.8 (3)
O1ii—Fe2—O3ii	89.41 (9)	C6—N1—C2	118.4 (2)
O1—Fe2—O3	89.41 (9)	C6—N1—Fe1	129.8 (2)
O1ii—Fe2—O3	90.59 (9)	C2—N1—Fe1	111.81 (18)
O3ii—Fe2—O3	180.0	Fe2—O1—H1A	122.3
O1—Fe2—O2	89.15 (10)	Fe2—O1—H1B	107.1
O1ii—Fe2—O2	90.85 (10)	H1A—O1—H1B	122.4
O3ii—Fe2—O2	93.74 (9)	Fe2—O2—H2B	122.9
O3—Fe2—O2	86.26 (9)	Fe2—O2—H2A	108.0
O1—Fe2—O2ii	90.85 (10)	H2B—O2—H2A	122.9
O1ii—Fe2—O2ii	89.15 (10)	C1—O3—Fe2	129.74 (18)
O3ii—Fe2—O2ii	86.26 (9)	C1—O4—Fe1	116.24 (18)
O3—Fe2—O2ii	93.74 (9)	Fe1—O5—H5A	104.8
O2—Fe2—O2ii	180.0	Fe1—O5—H5B	119.7
O3—C1—O4	125.5 (3)	H5A—O5—H5B	105.0
O3—C1—C2	117.1 (2)	H8B—O8—H8A	110.3
O4—C1—C2	117.3 (2)	H9B—O9—H9A	91.5
N1—C2—C3	122.2 (3)

D—H···A	D—H	H···A	D···A	D—H···A
O9—H9B···O8	0.85	2.32	3.159 (6)	171
O9—H9A···O6iii	0.85	2.06	2.849 (5)	154
O8—H8B···O5iv	0.85	2.55	3.204 (4)	134
O8—H8B···O4iv	0.85	2.51	3.171 (4)	136
O8—H8A···O3	0.85	2.55	3.177 (4)	132
O8—H8A···O2	0.85	2.44	3.201 (4)	149
O5—H5B···O7iii	0.85	2.22	2.706 (3)	116
O2—H2B···O9v	0.85	1.94	2.657 (5)	141
O2—H2A···O4ii	0.85	1.99	2.758 (3)	150
O1—H1B···O6vi	0.85	1.92	2.715 (3)	156
O1—H1A···O8iv	0.85	2.06	2.822 (4)	148

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O9—H9B⋯O8	0.85	2.32	3.159 (6)	171
O9—H9A⋯O6i	0.85	2.06	2.849 (5)	154
O8—H8B⋯O5ii	0.85	2.55	3.204 (4)	134
O8—H8B⋯O4ii	0.85	2.51	3.171 (4)	136
O8—H8A⋯O3	0.85	2.55	3.177 (4)	132
O8—H8A⋯O2	0.85	2.44	3.201 (4)	149
O5—H5B⋯O7i	0.85	2.22	2.706 (3)	116
O2—H2B⋯O9iii	0.85	1.94	2.657 (5)	141
O2—H2A⋯O4iv	0.85	1.99	2.758 (3)	150
O1—H1B⋯O6v	0.85	1.92	2.715 (3)	156
O1—H1A⋯O8ii	0.85	2.06	2.822 (4)	148

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) ; (v) .