Poly[[tetra-aqua-di-μ(4)-oxalato-μ(2)-oxalato-dineo-dymium(III)] dihydrate].

The title compound, {[Nd(2)(C(2)O(4))(3)(H(2)O)(4)]·2H(2)O}(n), was synthesized hydro-thermally in the presence of bis-(carb-oxy-ethyl-germanium) sesquioxide. It is isostructural with the corresponding Pr compound [Yang et al. (2009). Acta Cryst. E65, m1152-m1153]. The Nd(3+) cation is nine-coordinated and its coordination polyhedron can be described as a distorted tricapped trigonal prism. Two Nd(3+) ions are connected by two O atoms from two oxalate ions to give a dinuclear Nd(2) unit. The unit is further linked to four others via four oxalate ions yielding a layerparallel to (0-11). The linkages between the layers by neighbouring oxalate anions lead to a three-dimensional framework with channels along the c axis. The coordinating and free water mol-ecules are located in the channels and make contact with each other and the host framework by weak O-H⋯O hydrogen bonds.

Related literature

For the application of lanthanide compounds, see: Kido & Okamoto (2002 ▶). For background to lanthanide oxalates, see: Kahwa et al. (1984 ▶); Trombe & Jaud (2003 ▶); Wang et al. (2008 ▶). For the isostructural Pr compound, see: Yang et al. (2009 ▶).

Experimental

Crystal data

[Nd2(C2O4)3(H2O)4]·2H2O

M = 660.64

Triclinic,

a = 6.036 (3) Å

b = 7.603 (3) Å

c = 8.906 (4) Å

α = 98.386 (6)°

β = 99.742 (3)°

γ = 96.802 (5)°

V = 394.2 (3) Å3

Z = 1

Mo Kα radiation

μ = 6.61 mm−1

T = 293 K

0.05 × 0.05 × 0.05 mm

Data collection

Rigaku SCXmini diffractometer

Absorption correction: multi-scan (SADABS; Sheldrick, 2004 ▶) T min = 0.758, T max = 1.000

2997 measured reflections

1721 independent reflections

1600 reflections with I > 2σ(I)

R int = 0.019

Refinement

R[F 2 > 2σ(F 2)] = 0.019

wR(F 2) = 0.045

S = 1.04

1721 reflections

137 parameters

9 restraints

All H-atom parameters refined

Δρmax = 1.01 e Å−3

Δρmin = −1.06 e Å−3

Data collection: CrystalClear (Rigaku, 2007 ▶); cell refinement: CrystalClear; data reduction: CrystalClear; 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 datablock(s) I, global. DOI: 10.1107/S1600536812005016/fi2122sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812005016/fi2122Isup2.hkl

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

[Nd2(C2O4)3(H2O)4]·2H2O	Z = 1
Mr = 660.64	F(000) = 312
Triclinic, P1	Dx = 2.783 Mg m−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 6.036 (3) Å	Cell parameters from 1101 reflections
b = 7.603 (3) Å	θ = 2.4–27.5°
c = 8.906 (4) Å	µ = 6.61 mm−1
α = 98.386 (6)°	T = 293 K
β = 99.742 (3)°	Prism, pink
γ = 96.802 (5)°	0.05 × 0.05 × 0.05 mm
V = 394.2 (3) Å3

Rigaku SCXmini diffractometer	1721 independent reflections
Radiation source: fine-focus sealed tube	1600 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.019
ω scans	θmax = 27.5°, θmin = 3.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 2004)	h = −7→7
Tmin = 0.758, Tmax = 1.000	k = −9→9
2997 measured reflections	l = −11→11

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)] = 0.019	All H-atom parameters refined
wR(F2) = 0.045	w = 1/[σ2(Fo2) + (0.0267P)2] where P = (Fo2 + 2Fc2)/3
S = 1.04	(Δ/σ)max = 0.001
1721 reflections	Δρmax = 1.01 e Å−3
137 parameters	Δρmin = −1.06 e Å−3
9 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0250 (12)

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
Nd	0.50918 (3)	0.80732 (2)	0.795455 (19)	0.01243 (9)
O1	0.3007 (4)	0.6414 (3)	0.9553 (3)	0.0197 (5)
O2	0.2687 (4)	1.0032 (3)	0.9482 (3)	0.0159 (5)
O3	0.6296 (4)	0.7244 (3)	0.5432 (3)	0.0194 (5)
O4	0.7188 (4)	0.5888 (3)	0.9155 (3)	0.0218 (5)
O5	0.9212 (4)	0.8988 (3)	0.8085 (3)	0.0210 (5)
O6	0.3574 (5)	0.4917 (3)	0.6531 (3)	0.0227 (5)
C1	0.3797 (6)	0.5159 (4)	1.0114 (4)	0.0160 (7)
C2	0.0540 (5)	0.9720 (4)	0.9295 (4)	0.0138 (6)
C3	0.5789 (6)	0.5661 (4)	0.4686 (4)	0.0163 (7)
O1W	0.1774 (4)	0.8272 (4)	0.5951 (3)	0.0303 (7)
H1	0.052 (5)	0.846 (6)	0.618 (5)	0.045*
H2	0.145 (7)	0.765 (6)	0.509 (3)	0.045*
O2W	0.5617 (5)	1.0983 (4)	0.7077 (3)	0.0283 (6)
H3	0.461 (5)	1.144 (6)	0.658 (5)	0.042*
H4	0.680 (4)	1.171 (5)	0.722 (6)	0.042*
O3W	0.0780 (5)	0.6307 (4)	0.2901 (4)	0.0390 (8)
H5	0.105 (8)	0.550 (6)	0.226 (5)	0.059*
H6	−0.065 (3)	0.620 (7)	0.277 (6)	0.059*

	U11	U22	U33	U12	U13	U23
Nd	0.01250 (11)	0.01253 (11)	0.01129 (11)	−0.00015 (6)	0.00267 (6)	−0.00003 (6)
O1	0.0213 (13)	0.0226 (13)	0.0199 (12)	0.0078 (10)	0.0081 (10)	0.0099 (10)
O2	0.0100 (11)	0.0192 (12)	0.0172 (11)	0.0004 (9)	0.0032 (9)	−0.0006 (9)
O3	0.0231 (13)	0.0158 (12)	0.0170 (12)	−0.0022 (10)	0.0058 (10)	−0.0027 (10)
O4	0.0176 (13)	0.0249 (13)	0.0272 (13)	0.0047 (10)	0.0086 (10)	0.0123 (11)
O5	0.0137 (11)	0.0311 (14)	0.0140 (11)	−0.0038 (10)	0.0023 (9)	−0.0034 (10)
O6	0.0303 (14)	0.0191 (12)	0.0172 (12)	−0.0045 (10)	0.0128 (10)	−0.0047 (10)
C1	0.0177 (17)	0.0169 (16)	0.0125 (15)	0.0023 (13)	0.0028 (13)	−0.0001 (13)
C2	0.0131 (15)	0.0123 (14)	0.0153 (16)	0.0008 (12)	0.0025 (12)	0.0014 (13)
C3	0.0155 (16)	0.0179 (17)	0.0135 (15)	0.0021 (13)	0.0000 (12)	0.0000 (13)
O1W	0.0161 (13)	0.0518 (19)	0.0197 (13)	0.0077 (12)	0.0025 (10)	−0.0053 (13)
O2W	0.0261 (15)	0.0227 (14)	0.0342 (16)	−0.0029 (11)	−0.0005 (12)	0.0112 (12)
O3W	0.0284 (16)	0.0440 (18)	0.0356 (17)	−0.0137 (14)	0.0118 (13)	−0.0141 (14)

Nd—O1	2.441 (3)	O5—C2iii	1.241 (4)
Nd—O2W	2.455 (3)	O6—C3iv	1.248 (4)
Nd—O4	2.462 (3)	C1—O4ii	1.258 (5)
Nd—O5	2.480 (3)	C1—C1ii	1.542 (7)
Nd—O1W	2.481 (3)	C2—O5v	1.241 (4)
Nd—O3	2.494 (3)	C2—C2vi	1.539 (6)
Nd—O6	2.530 (3)	C3—O6iv	1.248 (4)
Nd—O2i	2.576 (2)	C3—C3iv	1.532 (7)
Nd—O2	2.601 (2)	O1W—H1	0.839 (19)
O1—C1	1.246 (4)	O1W—H2	0.823 (19)
O2—C2	1.267 (4)	O2W—H3	0.830 (18)
O2—Ndi	2.576 (2)	O2W—H4	0.827 (19)
O3—C3	1.263 (4)	O3W—H5	0.824 (19)
O4—C1ii	1.258 (5)	O3W—H6	0.845 (19)
O1—Nd—O2W	142.79 (9)	O4—Nd—O2	120.99 (8)
O1—Nd—O4	66.13 (8)	O5—Nd—O2	122.26 (8)
O2W—Nd—O4	142.62 (9)	O1W—Nd—O2	76.88 (8)
O1—Nd—O5	132.18 (8)	O3—Nd—O2	146.24 (8)
O2W—Nd—O5	71.58 (9)	O6—Nd—O2	122.82 (8)
O4—Nd—O5	71.43 (9)	O2i—Nd—O2	65.42 (9)
O1—Nd—O1W	97.08 (10)	C1—O1—Nd	120.1 (2)
O2W—Nd—O1W	70.46 (10)	C2—O2—Ndi	118.3 (2)
O4—Nd—O1W	142.10 (10)	C2—O2—Nd	123.74 (19)
O5—Nd—O1W	130.44 (10)	Ndi—O2—Nd	114.58 (8)
O1—Nd—O3	134.13 (8)	C3—O3—Nd	121.0 (2)
O2W—Nd—O3	77.81 (9)	C1ii—O4—Nd	119.4 (2)
O4—Nd—O3	92.73 (9)	C2iii—O5—Nd	123.2 (2)
O5—Nd—O3	67.13 (8)	C3iv—O6—Nd	120.3 (2)
O1W—Nd—O3	74.66 (9)	O1—C1—O4ii	126.2 (3)
O1—Nd—O6	70.15 (8)	O1—C1—C1ii	117.3 (4)
O2W—Nd—O6	132.48 (9)	O4ii—C1—C1ii	116.5 (4)
O4—Nd—O6	69.77 (9)	O5v—C2—O2	126.3 (3)
O5—Nd—O6	114.40 (8)	O5v—C2—C2vi	116.4 (4)
O1W—Nd—O6	72.59 (10)	O2—C2—C2vi	117.2 (3)
O3—Nd—O6	64.28 (8)	O6iv—C3—O3	125.9 (3)
O1—Nd—O2i	85.95 (9)	O6iv—C3—C3iv	117.0 (4)
O2W—Nd—O2i	81.77 (9)	O3—C3—C3iv	117.1 (4)
O4—Nd—O2i	77.35 (8)	Nd—O1W—H1	122 (3)
O5—Nd—O2i	63.77 (7)	Nd—O1W—H2	124 (3)
O1W—Nd—O2i	137.60 (8)	H1—O1W—H2	105 (3)
O3—Nd—O2i	130.55 (8)	Nd—O2W—H3	126 (3)
O6—Nd—O2i	144.97 (8)	Nd—O2W—H4	128 (3)
O1—Nd—O2	67.11 (8)	H3—O2W—H4	106 (3)
O2W—Nd—O2	75.84 (10)	H5—O3W—H6	105 (3)

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1···O5v	0.84 (2)	2.00 (3)	2.681 (4)	138 (4)
O1W—H1···O3v	0.84 (2)	2.55 (3)	3.244 (4)	141 (4)
O1W—H2···O3W	0.82 (2)	2.01 (2)	2.833 (4)	175 (5)
O2W—H3···O3vii	0.83 (2)	2.20 (3)	2.919 (4)	145 (4)
O2W—H4···O3Wvii	0.83 (2)	2.00 (2)	2.809 (4)	165 (4)
O3W—H5···O4iv	0.82 (2)	2.04 (2)	2.827 (4)	159 (5)
O3W—H6···O6viii	0.85 (2)	2.10 (4)	2.835 (4)	146 (5)

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1W—H1⋯O5i	0.84 (2)	2.00 (3)	2.681 (4)	138 (4)
O1W—H1⋯O3i	0.84 (2)	2.55 (3)	3.244 (4)	141 (4)
O1W—H2⋯O3W	0.82 (2)	2.01 (2)	2.833 (4)	175 (5)
O2W—H3⋯O3ii	0.83 (2)	2.20 (3)	2.919 (4)	145 (4)
O2W—H4⋯O3Wii	0.83 (2)	2.00 (2)	2.809 (4)	165 (4)
O3W—H5⋯O4iii	0.82 (2)	2.04 (2)	2.827 (4)	159 (5)
O3W—H6⋯O6iv	0.85 (2)	2.10 (4)	2.835 (4)	146 (5)

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