A new polymorph of catena-poly[[tri-aqua-cadmium(II)]-μ(2)-pyrazine-2,3-dicarboxyl-ato].

The title complex, [Cd(C(6)H(2)N(2)O(4))(H(2)O)(3)](n), is a new monoclinic polymorph. The ortho-rhom-bic form has previously been reported [Ma et al. (2006 ▶). Acta Cryst. E62, m2528-m2529]. The Cd-N and Cd-O bond lengths range from 2.265 (3) to 2.333 (3) Å; a weak Cd-O inter-action is also present, the inter-atomic distance being 2.658 (4) Å. The Cd(II) ions, which have a distorted penta-gonal-bipyramidal geometry, are bridged by pyrazine-2,3-dicarboxyl-ato ligands, forming a zigzag chain structure. The chains are connected by O-H⋯O hydrogen bonds into a three-dimensional framework.

Related literature

For the ortho­rhom­bic polymorph, see: Ma et al. (2006 ▶). For general background and related structures, see: Mao et al. (1996 ▶); Kitaura et al. (2002 ▶); Maji et al. (2004 ▶); Yin & Liu (2007 ▶, 2009 ▶).

Experimental

Crystal data

[Cd(C6H2N2O4)(H2O)3]

M = 332.54

Monoclinic,

a = 5.586 (6) Å

b = 15.748 (9) Å

c = 10.832 (6) Å

β = 93.94 (3)°

V = 950.5 (12) Å3

Z = 4

Mo Kα radiation

μ = 2.32 mm−1

T = 293 K

0.25 × 0.23 × 0.18 mm

Data collection

Rigaku Weissenberg IP diffractometer

Absorption correction: multi-scan (TEXRAY; Molecular Structure Corporation, 1999 ▶) T min = 0.668, T max = 1.000 (expected range = 0.440–0.658)

5659 measured reflections

2129 independent reflections

1699 reflections with I > 2σ(I)

R int = 0.032

Refinement

R[F 2 > 2σ(F 2)] = 0.030

wR(F 2) = 0.074

S = 1.03

2129 reflections

145 parameters

9 restraints

H-atom parameters constrained

Δρmax = 0.82 e Å−3

Δρmin = −0.53 e Å−3

Data collection: TEXRAY (Molecular Structure Corporation, 1999 ▶); cell refinement: TEXRAY; data reduction: TEXSAN (Molecular Structure Corporation, 1999 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEX (McArdle, 1995 ▶); software used to prepare material for publication: SHELXL97.

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809028268/bt5003sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809028268/bt5003Isup2.hkl

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

[Cd(C6H2N2O4)(H2O)3]	F(000) = 648
Mr = 332.54	Dx = 2.324 Mg m−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 4538 reflections
a = 5.586 (6) Å	θ = 3.2–27.5°
b = 15.748 (9) Å	µ = 2.32 mm−1
c = 10.832 (6) Å	T = 293 K
β = 93.94 (3)°	Block, colourless
V = 950.5 (12) Å3	0.25 × 0.23 × 0.18 mm
Z = 4

Weissenberg IP diffractometer	2129 independent reflections
Radiation source: rotor target	1699 reflections with I > 2σ(I)
graphite	Rint = 0.032
ω scans	θmax = 27.5°, θmin = 3.2°
Absorption correction: multi-scan (TEXRAY; Molecular Structure Corporation, 1999)	h = −7→5
Tmin = 0.668, Tmax = 1.000	k = −19→20
5659 measured reflections	l = −14→14

Refinement on F2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.030	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.074	H-atom parameters constrained
S = 1.03	w = 1/[σ2(Fo2) + (0.0366P)2 + 0.562P] where P = (Fo2 + 2Fc2)/3
2129 reflections	(Δ/σ)max < 0.001
145 parameters	Δρmax = 0.82 e Å−3
9 restraints	Δρmin = −0.53 e Å−3

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
Cd1	0.07189 (6)	0.372955 (14)	0.31158 (2)	0.02540 (10)
O1	0.3289 (6)	0.28668 (14)	0.2181 (2)	0.0294 (6)
O2	0.4160 (6)	0.15343 (17)	0.1696 (2)	0.0319 (7)
O3	0.3399 (7)	−0.01740 (17)	0.3172 (3)	0.0434 (8)
O4	0.1098 (7)	−0.00334 (19)	0.1449 (3)	0.0475 (9)
O1W	0.2872 (7)	0.34613 (18)	0.5126 (2)	0.0374 (7)
H1WA	0.3989	0.3785	0.5318	0.056*
H1WB	0.1887	0.3401	0.5663	0.056*
O2W	−0.2530 (6)	0.37407 (15)	0.1551 (3)	0.0358 (7)
H2WA	−0.3683	0.3410	0.1640	0.054*
H2WB	−0.3071	0.4212	0.1323	0.054*
O3W	−0.1846 (8)	0.4335 (2)	0.4320 (3)	0.0583 (11)
H3WA	−0.3095	0.4581	0.4013	0.088*
H3WB	−0.1945	0.4277	0.5076	0.088*
N1	−0.0445 (7)	0.23327 (16)	0.3472 (3)	0.0218 (7)
N2	−0.1324 (7)	0.06150 (18)	0.3781 (3)	0.0253 (7)
C1	0.0905 (7)	0.17535 (19)	0.2954 (3)	0.0194 (7)
C2	0.0436 (7)	0.0893 (2)	0.3109 (3)	0.0195 (7)
C3	−0.2626 (8)	0.1201 (2)	0.4287 (3)	0.0269 (8)
H3A	−0.3866	0.1031	0.4763	0.032*
C4	−0.2215 (8)	0.2060 (2)	0.4137 (3)	0.0242 (8)
H4A	−0.3187	0.2453	0.4505	0.029*
C5	0.2939 (8)	0.2074 (2)	0.2211 (3)	0.0216 (7)
C6	0.1817 (9)	0.0189 (2)	0.2531 (4)	0.0279 (9)

	U11	U22	U33	U12	U13	U23
Cd1	0.02614 (19)	0.01735 (14)	0.03381 (15)	0.00158 (10)	0.00999 (10)	0.00080 (10)
O1	0.029 (2)	0.0203 (10)	0.0414 (13)	−0.0017 (11)	0.0180 (12)	−0.0012 (10)
O2	0.027 (2)	0.0258 (12)	0.0445 (15)	−0.0003 (11)	0.0184 (13)	−0.0045 (11)
O3	0.043 (3)	0.0278 (13)	0.0605 (19)	0.0147 (14)	0.0148 (16)	0.0078 (13)
O4	0.044 (3)	0.0526 (17)	0.0482 (16)	−0.0186 (16)	0.0185 (15)	−0.0300 (14)
O1W	0.034 (2)	0.0431 (14)	0.0351 (14)	−0.0041 (13)	0.0042 (12)	0.0050 (12)
O2W	0.031 (2)	0.0274 (12)	0.0480 (15)	−0.0044 (12)	−0.0024 (13)	0.0038 (11)
O3W	0.053 (3)	0.089 (3)	0.0332 (14)	0.035 (2)	0.0059 (15)	−0.0104 (16)
N1	0.023 (2)	0.0185 (12)	0.0247 (13)	−0.0002 (11)	0.0056 (12)	−0.0004 (11)
N2	0.026 (2)	0.0217 (13)	0.0280 (14)	−0.0012 (12)	0.0035 (13)	0.0010 (11)
C1	0.022 (2)	0.0166 (14)	0.0198 (14)	0.0019 (13)	−0.0002 (13)	−0.0009 (12)
C2	0.017 (2)	0.0188 (14)	0.0233 (14)	0.0010 (13)	0.0038 (13)	0.0013 (12)
C3	0.024 (2)	0.0299 (17)	0.0273 (16)	−0.0027 (15)	0.0085 (14)	−0.0003 (14)
C4	0.022 (2)	0.0262 (16)	0.0253 (15)	0.0031 (14)	0.0095 (14)	−0.0030 (13)
C5	0.021 (2)	0.0202 (14)	0.0236 (14)	0.0020 (14)	0.0031 (14)	−0.0020 (13)
C6	0.025 (3)	0.0163 (14)	0.044 (2)	−0.0037 (15)	0.0156 (17)	−0.0055 (15)

Cd1—O3W	2.218 (3)	O2W—H2WB	0.8324
Cd1—O1	2.265 (3)	O3W—H3WA	0.8463
Cd1—O3i	2.294 (3)	O3W—H3WB	0.8295
Cd1—N1	2.334 (3)	N1—C1	1.332 (4)
Cd1—O2W	2.397 (4)	N1—C4	1.334 (5)
Cd1—O1W	2.451 (3)	N2—C3	1.317 (5)
O1—C5	1.265 (4)	N2—C2	1.337 (5)
O2—C5	1.245 (4)	C1—C2	1.393 (5)
O3—C6	1.226 (6)	C1—C5	1.522 (5)
O3—Cd1ii	2.294 (3)	C2—C6	1.510 (5)
O4—C6	1.262 (5)	C3—C4	1.384 (5)
O1W—H1WA	0.8214	C3—H3A	0.9300
O1W—H1WB	0.8327	C4—H4A	0.9300
O2W—H2WA	0.8385
O3W—Cd1—O1	167.27 (11)	Cd1—O3W—H3WB	128.5
O3W—Cd1—O3i	102.02 (13)	H3WA—O3W—H3WB	109.3
O1—Cd1—O3i	90.61 (11)	C1—N1—C4	118.0 (3)
O3W—Cd1—N1	96.29 (14)	C1—N1—Cd1	113.8 (2)
O1—Cd1—N1	72.59 (11)	C4—N1—Cd1	128.2 (2)
O3i—Cd1—N1	152.11 (10)	C3—N2—C2	116.5 (3)
O3W—Cd1—O2W	85.67 (14)	N1—C1—C2	119.9 (3)
O1—Cd1—O2W	99.25 (12)	N1—C1—C5	117.4 (3)
O3i—Cd1—O2W	75.44 (12)	C2—C1—C5	122.6 (3)
N1—Cd1—O2W	85.28 (11)	N2—C2—C1	122.4 (3)
O3W—Cd1—O1W	81.30 (13)	N2—C2—C6	113.7 (3)
O1—Cd1—O1W	90.37 (12)	C1—C2—C6	124.0 (3)
O3i—Cd1—O1W	123.85 (12)	N2—C3—C4	122.4 (4)
N1—Cd1—O1W	79.40 (11)	N2—C3—H3A	118.8
O2W—Cd1—O1W	158.60 (11)	C4—C3—H3A	118.8
C5—O1—Cd1	118.5 (2)	N1—C4—C3	120.9 (3)
C6—O3—Cd1ii	100.6 (2)	N1—C4—H4A	119.6
Cd1—O1W—H1WA	115.8	C3—C4—H4A	119.6
Cd1—O1W—H1WB	109.4	O2—C5—O1	124.9 (3)
H1WA—O1W—H1WB	114.9	O2—C5—C1	117.5 (3)
Cd1—O2W—H2WA	117.7	O1—C5—C1	117.6 (3)
Cd1—O2W—H2WB	117.3	O3—C6—O4	124.5 (4)
H2WA—O2W—H2WB	108.8	O3—C6—C2	118.4 (3)
Cd1—O3W—H3WA	120.9	O4—C6—C2	116.7 (4)
O3W—Cd1—O1—C5	32.7 (8)	N1—C1—C2—N2	−0.9 (6)
O3i—Cd1—O1—C5	−154.6 (3)	C5—C1—C2—N2	178.7 (3)
N1—Cd1—O1—C5	2.8 (3)	N1—C1—C2—C6	178.3 (3)
O2W—Cd1—O1—C5	−79.2 (3)	C5—C1—C2—C6	−2.1 (6)
O1W—Cd1—O1—C5	81.6 (3)	C2—N2—C3—C4	0.1 (6)
O3W—Cd1—N1—C1	−174.6 (3)	C1—N1—C4—C3	0.3 (6)
O1—Cd1—N1—C1	−0.9 (2)	Cd1—N1—C4—C3	−178.0 (3)
O3i—Cd1—N1—C1	54.4 (4)	N2—C3—C4—N1	−0.5 (6)
O2W—Cd1—N1—C1	100.3 (3)	Cd1—O1—C5—O2	177.2 (3)
O1W—Cd1—N1—C1	−94.7 (3)	Cd1—O1—C5—C1	−4.1 (4)
O3W—Cd1—N1—C4	3.8 (4)	N1—C1—C5—O2	−178.0 (3)
O1—Cd1—N1—C4	177.4 (4)	C2—C1—C5—O2	2.4 (5)
O3i—Cd1—N1—C4	−127.3 (3)	N1—C1—C5—O1	3.3 (5)
O2W—Cd1—N1—C4	−81.3 (3)	C2—C1—C5—O1	−176.4 (4)
O1W—Cd1—N1—C4	83.7 (3)	Cd1ii—O3—C6—O4	−2.1 (5)
C4—N1—C1—C2	0.4 (5)	Cd1ii—O3—C6—C2	171.1 (3)
Cd1—N1—C1—C2	178.9 (3)	N2—C2—C6—O3	−81.2 (5)
C4—N1—C1—C5	−179.2 (3)	C1—C2—C6—O3	99.6 (5)
Cd1—N1—C1—C5	−0.7 (4)	N2—C2—C6—O4	92.5 (4)
C3—N2—C2—C1	0.6 (6)	C1—C2—C6—O4	−86.7 (5)
C3—N2—C2—C6	−178.6 (3)

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1WA···O4iii	0.82	2.56	3.328 (5)	156
O2W—H2WA···O1iv	0.84	2.02	2.834 (5)	164
O2W—H2WB···N2v	0.83	2.24	3.036 (4)	161
O3W—H3WA···O4v	0.85	1.82	2.656 (6)	169
O3W—H3WB···O4vi	0.83	2.25	2.865 (4)	132
O3W—H3WB···O2vi	0.83	2.22	2.935 (4)	144

Table 1

Selected geometric parameters (Å, °)

Cd1—O3W	2.218 (3)
Cd1—O1	2.265 (3)
Cd1—O3i	2.294 (3)
Cd1—N1	2.334 (3)
Cd1—O2W	2.397 (4)
Cd1—O1W	2.451 (3)

Symmetry code: (i) .

Table 2

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1W—H1WA⋯O4ii	0.82	2.56	3.328 (5)	156
O2W—H2WA⋯O1iii	0.84	2.02	2.834 (5)	164
O2W—H2WB⋯N2iv	0.83	2.24	3.036 (4)	161
O3W—H3WA⋯O4iv	0.85	1.82	2.656 (6)	169
O3W—H3WB⋯O4v	0.83	2.25	2.865 (4)	132
O3W—H3WB⋯O2v	0.83	2.22	2.935 (4)	144

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