Poly[tetra­aqua­bis­(μ3-oxalato-κ5O1,O2:O1′:O1′,O2′)(μ2-oxalato-κ4O1,O2:O1′,O2′)dipraseodymium(III)]

Hao, C.-J.; Xie, H.

doi:10.1107/S1600536812011014

metal-organic compounds

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ISSN: 2056-9890

Volume 68| Part 4| April 2012| Page m444

doi:10.1107/S1600536812011014

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Poly[tetraaquabis(μ₃-oxalato-κ⁵O¹,O²:O^1′:O^1′,O^2′)(μ₂-oxalato-κ⁴O¹,O²:O^1′,O^2′)dipraseodymium(III)]

Cheng-Jun Hao ^a ^* and Hui Xie ^a

^aCollege of Chemistry and Chemical Engineering, Pingdingshan University, Pingdingshan 467000, People's Republic of China
^*Correspondence e-mail: haochengjun2008@163.com

(Received 23 February 2012; accepted 13 March 2012; online 17 March 2012)

In the title complex, [Pr₂(C₂O₄)₃(H₂O)₄]_n, the two independent Pr^III ions are both nine-coordinated in a distorted monocapped square-antiprismatic geometry by seven O atoms from four oxalate ligands and two water molecules. The Pr^III ions are bridged by the oxalate ligands, forming a layer parallel to (001). O—H⋯O hydrogen bonds connect the layers.

Related literature

For the structures and potential applications of lanthanide complexes, see: Ma et al. (2001 ); Shibasaki & Yoshikawa (2002 ); Song et al. (2012 ).

Experimental

Crystal data

[Pr₂(C₂O₄)₃(H₂O)₄]
M_r = 617.94
Orthorhombic, P 2₁ 2₁ 2₁
a = 8.6358 (17) Å
b = 9.5356 (19) Å
c = 16.885 (3) Å
V = 1390.4 (5) Å³
Z = 4
Mo Kα radiation
μ = 7.02 mm⁻¹
T = 293 K
0.23 × 0.22 × 0.20 mm

Data collection

Rigaku Mercury CCD diffractometer
Absorption correction: multi-scan (CrystalClear; Rigaku, 2002 ) T_min = 0.295, T_max = 0.334
13654 measured reflections
3181 independent reflections
2826 reflections with I > 2σ(I)
R_int = 0.047

Refinement

R[F² > 2σ(F²)] = 0.029
wR(F²) = 0.072
S = 1.04
3181 reflections
217 parameters
H-atom parameters constrained
Δρ_max = 1.34 e Å⁻³
Δρ_min = −1.44 e Å⁻³
Absolute structure: Flack (1983 ), 1344 Friedel pairs
Flack parameter: 0.49 (3)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1W—H1W⋯O2ⁱ	0.85	2.02	2.852 (6)	166
O1W—H2W⋯O8ⁱⁱ	0.85	2.15	2.998 (6)	173
O2W—H3W⋯O4ⁱⁱⁱ	0.85	2.40	2.998 (6)	128
O2W—H4W⋯O6^iv	0.85	2.01	2.792 (6)	152
O3W—H5W⋯O12^v	0.85	1.97	2.780 (6)	158
O3W—H6W⋯O3^v	0.85	2.60	3.379 (7)	154
O4W—H7W⋯O1^vi	0.85	2.16	2.865 (6)	140
O4W—H8W⋯O9^v	0.85	2.04	2.882 (6)	169
Symmetry codes: (i) $[x+{\script{1\over 2}}, -y+{\script{3\over 2}}, -z]$ ; (ii) $[x-{\script{1\over 2}}, -y+{\script{3\over 2}}, -z]$ ; (iii) x+1, y, z; (iv) $[-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (v) $[x-{\script{1\over 2}}, -y+{\script{1\over 2}}, -z]$ ; (vi) x-1, y, z.

Data collection: CrystalClear (Rigaku, 2002); cell refinement: CrystalClear; data reduction: CrystalStructure (Rigaku/MSC, 2002 ); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPII (Johnson, 1976 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812011014/hy2521sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812011014/hy2521Isup2.hkl

checkCIF report

Comment top

During the past decade, considerable efforts have been devoted to the design and construction of new lanthanide coordination polymers due to their intriguing structural diversity and potential applications in many areas (Ma et al., 2001; Shibasaki & Yoshikawa, 2002; Song et al., 2012). Oxalate owning four carboxylate O atoms is highly accessible to lanthanide ions to form novel structures.

As shown in Fig. 1, in the asymmetric unit of the title complex, there are two independent Pr^III ions with a similar coordination environment. Each Pr^III ion is nine-coordinated by seven O atoms from four oxalate ligands and two O atoms from two terminal water molecules. The Pr1 and Pr2 atoms are bridged by two carboxylate O atoms, forming a Pr₂O₂ subunit with a Pr···Pr distance of 4.2893 (7) Å. Such subunits are connected by the oxalate ligands, generating a layer parallel to (0 0 1). It is noted that the oxalate ligands exhibit two kinds of coordination modes: one adopts a bisbidentate coordination mode bridging two Pr^III ions; the other adopts a chelating and bridging coordination mode connecting three Pr^III ions. The adjacent layers are further linked into a three-dimensional network via intermolecular O—H···O hydrogen bonds (Table 1).

Related literature top

For the structures and potential applications of lanthanide complexes, see: Ma et al. (2001); Shibasaki & Yoshikawa (2002); Song et al. (2012).

Experimental top

A mixture of Pr(NO₃)₃.6H₂O (0.5 mmol, 0.217 g) and oxalic acid (1 mmol, 0.09 g) in 10 ml of H₂O was sealed in an autoclave equipped with a Teflon liner (30 ml) and then heated to 453 K for 4 days. After gradual cooling to room temperature, crystals were obtained and collected by filtration with a yield of 31% based on Pr.

Structure description top

For the structures and potential applications of lanthanide complexes, see: Ma et al. (2001); Shibasaki & Yoshikawa (2002); Song et al. (2012).

Computing details top

Data collection: CrystalClear (Rigaku, 2002); cell refinement: CrystalClear (Rigaku, 2002); data reduction: CrystalStructure (Rigaku/MSC, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

Fig. 1. The asymmetric unit of the title compound. Displacement ellipsoids are drawn at the 30% probability level. H atoms are omitted for clarity. [Symmetry codes: (i) x, y+1, z; (ii) -x+1, y-1/2, -z+1/2; (iii) x-1, y-1, z; (iv) -x, y+1/2, -z+1/2.]

Poly[tetraaquabis(µ₃-oxalato- κ⁵O¹,O²:O^1':O^1',O^2')(µ₂- oxalato- κ⁴O¹,O²:O^1',O^2')dipraseodymium(III)] top

Crystal data top

[Pr₂(C₂O₄)₃(H₂O)₄]	F(000) = 1160
M_r = 617.94	D_x = 2.952 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 3600 reflections
a = 8.6358 (17) Å	θ = 1.4–28.0°
b = 9.5356 (19) Å	µ = 7.02 mm⁻¹
c = 16.885 (3) Å	T = 293 K
V = 1390.4 (5) Å³	Block, green
Z = 4	0.23 × 0.22 × 0.20 mm

Data collection top

Rigaku Mercury CCD diffractometer	3181 independent reflections
Radiation source: fine-focus sealed tube	2826 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.047
ω scans	θ_max = 27.4°, θ_min = 3.2°
Absorption correction: multi-scan (CrystalClear; Rigaku, 2002)	h = −9→11
T_min = 0.295, T_max = 0.334	k = −12→12
13654 measured reflections	l = −21→21

Refinement top

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)] = 0.029	H-atom parameters constrained
wR(F²) = 0.072	w = 1/[σ²(F_o²) + (0.0284P)² + 3.201P] where P = (F_o² + 2F_c²)/3
S = 1.04	(Δ/σ)_max = 0.001
3181 reflections	Δρ_max = 1.34 e Å⁻³
217 parameters	Δρ_min = −1.44 e Å⁻³
0 restraints	Absolute structure: Flack (1983), 1344 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.49 (3)

Crystal data top

[Pr₂(C₂O₄)₃(H₂O)₄]	V = 1390.4 (5) Å³
M_r = 617.94	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 8.6358 (17) Å	µ = 7.02 mm⁻¹
b = 9.5356 (19) Å	T = 293 K
c = 16.885 (3) Å	0.23 × 0.22 × 0.20 mm

Data collection top

Rigaku Mercury CCD diffractometer	3181 independent reflections
Absorption correction: multi-scan (CrystalClear; Rigaku, 2002)	2826 reflections with I > 2σ(I)
T_min = 0.295, T_max = 0.334	R_int = 0.047
13654 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.029	H-atom parameters constrained
wR(F²) = 0.072	Δρ_max = 1.34 e Å⁻³
S = 1.04	Δρ_min = −1.44 e Å⁻³
3181 reflections	Absolute structure: Flack (1983), 1344 Friedel pairs
217 parameters	Absolute structure parameter: 0.49 (3)
0 restraints

Special details top

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 (Å²) top

	x	y	z	U_iso*/U_eq
Pr1	0.37510 (4)	0.75389 (2)	0.143154 (14)	0.01214 (9)
Pr2	−0.12589 (4)	0.26126 (3)	0.137142 (14)	0.01185 (8)
O1	0.3263 (5)	0.4984 (4)	0.1336 (3)	0.0245 (10)
O2	0.1023 (5)	0.6852 (4)	0.1081 (2)	0.0220 (9)
O3	0.1479 (5)	0.3304 (5)	0.1473 (3)	0.0383 (12)
O4	−0.0761 (5)	0.5159 (5)	0.1102 (3)	0.0236 (10)
O5	0.5734 (5)	0.8913 (4)	0.0744 (2)	0.0220 (9)
O6	0.4832 (5)	0.9677 (5)	0.2184 (2)	0.0221 (9)
O7	0.6490 (5)	1.1490 (4)	0.2172 (2)	0.0209 (9)
O8	0.7467 (5)	1.0643 (5)	0.0716 (3)	0.0255 (10)
O9	0.0572 (5)	0.0999 (5)	0.0683 (2)	0.0205 (9)
O10	−0.0198 (5)	0.0560 (4)	0.2191 (2)	0.0230 (9)
O11	0.1596 (4)	−0.1155 (4)	0.2289 (2)	0.0186 (9)
O12	0.2521 (5)	−0.0484 (4)	0.0791 (2)	0.0219 (9)
O1W	0.4097 (7)	0.6778 (5)	0.0052 (2)	0.0361 (14)
H1W	0.4747	0.7253	−0.0215	0.054*
H2W	0.3561	0.6140	−0.0168	0.054*
O2W	0.6418 (6)	0.6597 (5)	0.1743 (3)	0.0357 (11)
H3W	0.7010	0.6599	0.1341	0.053*
H4W	0.6369	0.5950	0.2088	0.053*
O3W	−0.1196 (7)	0.3125 (5)	−0.0081 (2)	0.0296 (10)
H5W	−0.1447	0.3960	−0.0200	0.044*
H6W	−0.1567	0.2530	−0.0404	0.044*
O4W	−0.3828 (6)	0.3679 (5)	0.0986 (2)	0.0303 (10)
H7W	−0.4443	0.4093	0.1304	0.045*
H8W	−0.4120	0.3834	0.0513	0.045*
C1	0.1907 (7)	0.4536 (6)	0.1341 (4)	0.0214 (13)
C2	0.0597 (7)	0.5610 (6)	0.1160 (3)	0.0196 (12)
C3	0.6393 (7)	0.9949 (6)	0.1035 (3)	0.0160 (12)
C4	0.5861 (6)	1.0398 (6)	0.1870 (3)	0.0169 (12)
C5	0.1355 (7)	0.0127 (5)	0.1057 (3)	0.0164 (11)
C6	0.0863 (6)	−0.0190 (6)	0.1925 (3)	0.0166 (12)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Pr1	0.01379 (15)	0.00894 (14)	0.01370 (14)	−0.00143 (13)	0.00092 (11)	0.00098 (9)
Pr2	0.01324 (15)	0.00861 (13)	0.01371 (14)	−0.00137 (13)	0.00076 (12)	−0.00112 (9)
O1	0.025 (2)	0.013 (2)	0.035 (2)	−0.0023 (16)	−0.001 (2)	0.0004 (18)
O2	0.019 (2)	0.019 (2)	0.028 (2)	−0.0007 (18)	−0.0038 (19)	0.0043 (16)
O3	0.018 (2)	0.0103 (19)	0.086 (4)	−0.0033 (18)	−0.005 (2)	0.009 (2)
O4	0.022 (2)	0.018 (2)	0.031 (2)	−0.0029 (16)	−0.0023 (19)	0.0017 (18)
O5	0.030 (2)	0.015 (2)	0.020 (2)	−0.0103 (17)	0.0063 (18)	−0.0088 (17)
O6	0.025 (2)	0.025 (2)	0.0165 (18)	−0.0139 (18)	0.0081 (18)	−0.0051 (18)
O7	0.028 (2)	0.0162 (19)	0.0188 (18)	−0.0058 (17)	0.0033 (19)	−0.0052 (15)
O8	0.030 (2)	0.022 (3)	0.024 (2)	−0.0126 (19)	0.010 (2)	−0.0098 (19)
O9	0.025 (2)	0.020 (2)	0.0162 (19)	0.0110 (18)	0.0016 (18)	0.0036 (17)
O10	0.027 (2)	0.024 (2)	0.019 (2)	0.0093 (18)	0.0056 (19)	0.0051 (19)
O11	0.021 (2)	0.019 (2)	0.0155 (18)	0.0023 (16)	−0.0005 (17)	0.0045 (15)
O12	0.027 (2)	0.017 (2)	0.022 (2)	0.0088 (18)	0.0093 (18)	0.0092 (18)
O1W	0.056 (4)	0.027 (3)	0.025 (2)	−0.023 (2)	0.016 (2)	−0.0094 (17)
O2W	0.030 (3)	0.030 (3)	0.046 (3)	0.008 (2)	0.003 (3)	0.006 (2)
O3W	0.046 (3)	0.020 (2)	0.024 (2)	0.007 (3)	0.002 (2)	0.0062 (15)
O4W	0.027 (2)	0.038 (3)	0.027 (2)	0.008 (2)	−0.001 (2)	0.0004 (17)
C1	0.022 (3)	0.013 (3)	0.029 (3)	−0.003 (2)	0.002 (3)	0.000 (3)
C2	0.027 (3)	0.018 (3)	0.014 (3)	−0.001 (2)	0.000 (2)	−0.001 (2)
C3	0.016 (3)	0.015 (3)	0.017 (3)	0.002 (3)	0.004 (3)	−0.0010 (18)
C4	0.021 (3)	0.014 (3)	0.015 (3)	−0.001 (2)	−0.001 (2)	−0.002 (2)
C5	0.022 (3)	0.009 (3)	0.018 (3)	0.000 (3)	0.000 (3)	0.0023 (18)
C6	0.020 (3)	0.016 (3)	0.014 (2)	−0.001 (2)	−0.002 (2)	0.002 (2)

Geometric parameters (Å, º) top

Pr1—O12ⁱ	2.419 (4)	O4—C2	1.253 (7)
Pr1—O5	2.449 (4)	O5—C3	1.241 (6)
Pr1—O1W	2.458 (4)	O6—C4	1.242 (7)
Pr1—O1	2.478 (4)	O7—C4	1.281 (7)
Pr1—O2	2.516 (4)	O8—C3	1.261 (7)
Pr1—O2W	2.527 (5)	O9—C5	1.244 (7)
Pr1—O7ⁱⁱ	2.570 (4)	O10—C6	1.247 (7)
Pr1—O6	2.578 (4)	O11—C6	1.275 (7)
Pr1—O11ⁱ	2.666 (4)	O12—C5	1.247 (7)
Pr2—O8ⁱⁱⁱ	2.442 (4)	O1W—H1W	0.8500
Pr2—O3	2.460 (4)	O1W—H2W	0.8501
Pr2—O9	2.494 (4)	O2W—H3W	0.8500
Pr2—O3W	2.501 (4)	O2W—H4W	0.8500
Pr2—O4	2.508 (4)	O3W—H5W	0.8500
Pr2—O4W	2.526 (5)	O3W—H6W	0.8499
Pr2—O11^iv	2.565 (4)	O4W—H7W	0.8511
Pr2—O10	2.566 (4)	O4W—H8W	0.8513
Pr2—O7ⁱⁱⁱ	2.598 (4)	C1—C2	1.556 (9)
O1—C1	1.247 (7)	C3—C4	1.544 (7)
O2—C2	1.247 (7)	C5—C6	1.555 (8)
O3—C1	1.252 (7)

O12ⁱ—Pr1—O5	71.23 (15)	O9—Pr2—O10	63.55 (13)
O12ⁱ—Pr1—O1W	81.93 (16)	O3W—Pr2—O10	132.08 (14)
O5—Pr1—O1W	67.89 (15)	O4—Pr2—O10	140.82 (14)
O12ⁱ—Pr1—O1	131.49 (15)	O4W—Pr2—O10	139.42 (14)
O5—Pr1—O1	127.89 (14)	O11^iv—Pr2—O10	85.07 (13)
O1W—Pr1—O1	70.66 (15)	O8ⁱⁱⁱ—Pr2—O7ⁱⁱⁱ	65.29 (13)
O12ⁱ—Pr1—O2	71.72 (14)	O3—Pr2—O7ⁱⁱⁱ	142.48 (15)
O5—Pr1—O2	133.05 (13)	O9—Pr2—O7ⁱⁱⁱ	117.55 (13)
O1W—Pr1—O2	79.30 (16)	O3W—Pr2—O7ⁱⁱⁱ	127.34 (15)
O1—Pr1—O2	64.51 (14)	O4—Pr2—O7ⁱⁱⁱ	128.43 (13)
O12ⁱ—Pr1—O2W	140.37 (15)	O4W—Pr2—O7ⁱⁱⁱ	69.05 (14)
O5—Pr1—O2W	69.61 (15)	O11^iv—Pr2—O7ⁱⁱⁱ	69.21 (11)
O1W—Pr1—O2W	88.94 (17)	O10—Pr2—O7ⁱⁱⁱ	70.88 (13)
O1—Pr1—O2W	79.57 (15)	C1—O1—Pr1	119.7 (4)
O2—Pr1—O2W	144.08 (15)	C2—O2—Pr1	119.9 (4)
O12ⁱ—Pr1—O7ⁱⁱ	132.68 (13)	C1—O3—Pr2	121.5 (4)
O5—Pr1—O7ⁱⁱ	134.42 (14)	C2—O4—Pr2	118.6 (4)
O1W—Pr1—O7ⁱⁱ	139.87 (15)	C3—O5—Pr1	123.9 (4)
O1—Pr1—O7ⁱⁱ	70.32 (14)	C4—O6—Pr1	119.1 (3)
O2—Pr1—O7ⁱⁱ	92.21 (13)	C4—O7—Pr1^v	130.3 (3)
O2W—Pr1—O7ⁱⁱ	75.20 (14)	C4—O7—Pr2^vi	116.5 (3)
O12ⁱ—Pr1—O6	76.29 (15)	Pr1^v—O7—Pr2^vi	112.19 (14)
O5—Pr1—O6	63.73 (12)	C3—O8—Pr2^vi	122.8 (3)
O1W—Pr1—O6	131.05 (14)	C5—O9—Pr2	121.3 (4)
O1—Pr1—O6	150.63 (14)	C6—O10—Pr2	120.4 (3)
O2—Pr1—O6	131.37 (13)	C6—O11—Pr2^vii	134.4 (3)
O2W—Pr1—O6	81.29 (14)	C6—O11—Pr1^viii	114.9 (3)
O7ⁱⁱ—Pr1—O6	83.38 (13)	Pr2^vii—O11—Pr1^viii	110.13 (14)
O12ⁱ—Pr1—O11ⁱ	64.69 (12)	C5—O12—Pr1^viii	123.9 (3)
O5—Pr1—O11ⁱ	119.72 (13)	Pr1—O1W—H1W	115.2
O1W—Pr1—O11ⁱ	137.50 (16)	Pr1—O1W—H2W	124.0
O1—Pr1—O11ⁱ	112.07 (13)	H1W—O1W—H2W	120.6
O2—Pr1—O11ⁱ	66.14 (12)	Pr1—O2W—H3W	112.4
O2W—Pr1—O11ⁱ	133.55 (12)	Pr1—O2W—H4W	110.8
O7ⁱⁱ—Pr1—O11ⁱ	68.09 (12)	H3W—O2W—H4W	125.4
O6—Pr1—O11ⁱ	67.40 (12)	Pr2—O3W—H5W	114.3
O8ⁱⁱⁱ—Pr2—O3	132.12 (15)	Pr2—O3W—H6W	119.4
O8ⁱⁱⁱ—Pr2—O9	66.40 (15)	H5W—O3W—H6W	112.1
O3—Pr2—O9	65.72 (15)	Pr2—O4W—H7W	124.9
O8ⁱⁱⁱ—Pr2—O3W	73.46 (15)	Pr2—O4W—H8W	124.9
O3—Pr2—O3W	89.72 (18)	H7W—O4W—H8W	109.1
O9—Pr2—O3W	69.50 (14)	O1—C1—O3	126.9 (6)
O8ⁱⁱⁱ—Pr2—O4	137.69 (15)	O1—C1—C2	117.2 (5)
O3—Pr2—O4	65.69 (14)	O3—C1—C2	116.0 (5)
O9—Pr2—O4	113.85 (14)	O2—C2—O4	126.4 (6)
O3W—Pr2—O4	68.22 (15)	O2—C2—C1	115.6 (5)
O8ⁱⁱⁱ—Pr2—O4W	78.30 (16)	O4—C2—C1	118.0 (5)
O3—Pr2—O4W	138.94 (15)	O5—C3—O8	125.9 (5)
O9—Pr2—O4W	133.26 (13)	O5—C3—C4	116.5 (5)
O3W—Pr2—O4W	71.82 (15)	O8—C3—C4	117.6 (5)
O4—Pr2—O4W	73.38 (14)	O6—C4—O7	125.7 (5)
O8ⁱⁱⁱ—Pr2—O11^iv	134.49 (13)	O6—C4—C3	116.7 (5)
O3—Pr2—O11^iv	85.69 (15)	O7—C4—C3	117.6 (5)
O9—Pr2—O11^iv	139.96 (13)	O9—C5—O12	124.6 (5)
O3W—Pr2—O11^iv	141.03 (13)	O9—C5—C6	117.4 (5)
O4—Pr2—O11^iv	74.70 (14)	O12—C5—C6	118.0 (5)
O4W—Pr2—O11^iv	86.72 (13)	O10—C6—O11	127.2 (5)
O8ⁱⁱⁱ—Pr2—O10	79.57 (15)	O10—C6—C5	115.4 (5)
O3—Pr2—O10	79.85 (14)	O11—C6—C5	117.3 (5)

O12ⁱ—Pr1—O1—C1	−43.6 (5)	O4W—Pr2—O9—C5	−146.9 (4)
O5—Pr1—O1—C1	−141.8 (4)	O11^iv—Pr2—O9—C5	29.4 (5)
O1W—Pr1—O1—C1	−103.0 (5)	O10—Pr2—O9—C5	−12.7 (4)
O2—Pr1—O1—C1	−15.9 (4)	O7ⁱⁱⁱ—Pr2—O9—C5	−60.5 (5)
O2W—Pr1—O1—C1	164.5 (5)	O8ⁱⁱⁱ—Pr2—O10—C6	77.6 (4)
O7ⁱⁱ—Pr1—O1—C1	86.6 (5)	O3—Pr2—O10—C6	−58.9 (4)
O6—Pr1—O1—C1	114.3 (5)	O9—Pr2—O10—C6	8.9 (4)
O11ⁱ—Pr1—O1—C1	31.5 (5)	O3W—Pr2—O10—C6	21.4 (5)
O12ⁱ—Pr1—O2—C2	171.5 (4)	O4—Pr2—O10—C6	−87.1 (5)
O5—Pr1—O2—C2	132.1 (4)	O4W—Pr2—O10—C6	135.4 (4)
O1W—Pr1—O2—C2	86.6 (4)	O11^iv—Pr2—O10—C6	−145.4 (4)
O1—Pr1—O2—C2	13.0 (4)	O7ⁱⁱⁱ—Pr2—O10—C6	144.9 (5)
O2W—Pr1—O2—C2	13.6 (5)	Pr1—O1—C1—O3	−163.0 (6)
O7ⁱⁱ—Pr1—O2—C2	−53.9 (4)	Pr1—O1—C1—C2	17.5 (7)
O6—Pr1—O2—C2	−137.1 (4)	Pr2—O3—C1—O1	−176.1 (5)
O11ⁱ—Pr1—O2—C2	−118.8 (4)	Pr2—O3—C1—C2	3.5 (8)
O8ⁱⁱⁱ—Pr2—O3—C1	132.1 (5)	Pr1—O2—C2—O4	170.7 (5)
O9—Pr2—O3—C1	132.4 (6)	Pr1—O2—C2—C1	−9.8 (7)
O3W—Pr2—O3—C1	64.9 (5)	Pr2—O4—C2—O2	−176.5 (5)
O4—Pr2—O3—C1	−1.2 (5)	Pr2—O4—C2—C1	4.0 (7)
O4W—Pr2—O3—C1	3.6 (6)	O1—C1—C2—O2	−5.0 (8)
O11^iv—Pr2—O3—C1	−76.4 (5)	O3—C1—C2—O2	175.4 (6)
O10—Pr2—O3—C1	−162.1 (5)	O1—C1—C2—O4	174.6 (5)
O7ⁱⁱⁱ—Pr2—O3—C1	−123.3 (5)	O3—C1—C2—O4	−5.0 (9)
O8ⁱⁱⁱ—Pr2—O4—C2	−128.4 (4)	Pr1—O5—C3—O8	176.5 (5)
O3—Pr2—O4—C2	−1.8 (4)	Pr1—O5—C3—C4	−2.1 (7)
O9—Pr2—O4—C2	−47.9 (5)	Pr2^vi—O8—C3—O5	−177.6 (5)
O3W—Pr2—O4—C2	−101.8 (5)	Pr2^vi—O8—C3—C4	1.0 (7)
O4W—Pr2—O4—C2	−178.4 (5)	Pr1—O6—C4—O7	179.3 (4)
O11^iv—Pr2—O4—C2	90.4 (4)	Pr1—O6—C4—C3	0.9 (6)
O10—Pr2—O4—C2	28.9 (5)	Pr1^v—O7—C4—O6	8.5 (9)
O7ⁱⁱⁱ—Pr2—O4—C2	137.0 (4)	Pr2^vi—O7—C4—O6	175.9 (5)
O12ⁱ—Pr1—O5—C3	85.5 (5)	Pr1^v—O7—C4—C3	−173.1 (3)
O1W—Pr1—O5—C3	174.2 (5)	Pr2^vi—O7—C4—C3	−5.7 (6)
O1—Pr1—O5—C3	−146.1 (4)	O5—C3—C4—O6	0.7 (8)
O2—Pr1—O5—C3	125.0 (4)	O8—C3—C4—O6	−178.0 (6)
O2W—Pr1—O5—C3	−88.3 (5)	O5—C3—C4—O7	−177.8 (6)
O7ⁱⁱ—Pr1—O5—C3	−46.6 (5)	O8—C3—C4—O7	3.4 (8)
O6—Pr1—O5—C3	1.8 (4)	Pr2—O9—C5—O12	−163.2 (4)
O11ⁱ—Pr1—O5—C3	41.0 (5)	Pr2—O9—C5—C6	15.3 (7)
O12ⁱ—Pr1—O6—C4	−76.9 (4)	Pr1^viii—O12—C5—O9	−168.6 (4)
O5—Pr1—O6—C4	−1.3 (4)	Pr1^viii—O12—C5—C6	12.9 (7)
O1W—Pr1—O6—C4	−10.7 (5)	Pr2—O10—C6—O11	173.1 (4)
O1—Pr1—O6—C4	120.0 (4)	Pr2—O10—C6—C5	−5.4 (7)
O2—Pr1—O6—C4	−126.7 (4)	Pr2^vii—O11—C6—O10	9.0 (9)
O2W—Pr1—O6—C4	70.2 (4)	Pr1^viii—O11—C6—O10	179.4 (5)
O7ⁱⁱ—Pr1—O6—C4	146.1 (4)	Pr2^vii—O11—C6—C5	−172.6 (3)
O11ⁱ—Pr1—O6—C4	−144.9 (4)	Pr1^viii—O11—C6—C5	−2.2 (6)
O8ⁱⁱⁱ—Pr2—O9—C5	−102.6 (5)	O9—C5—C6—O10	−6.3 (8)
O3—Pr2—O9—C5	77.7 (4)	O12—C5—C6—O10	172.3 (5)
O3W—Pr2—O9—C5	177.1 (5)	O9—C5—C6—O11	175.1 (5)
O4—Pr2—O9—C5	123.9 (4)	O12—C5—C6—O11	−6.4 (8)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1W···O2^ix	0.85	2.02	2.852 (6)	166
O1W—H2W···O8^x	0.85	2.15	2.998 (6)	173
O2W—H3W···O4^xi	0.85	2.40	2.998 (6)	128
O2W—H4W···O6ⁱⁱ	0.85	2.01	2.792 (6)	152
O3W—H5W···O12^xii	0.85	1.97	2.780 (6)	158
O3W—H6W···O3^xii	0.85	2.60	3.379 (7)	154
O4W—H7W···O1^xiii	0.85	2.16	2.865 (6)	140
O4W—H8W···O9^xii	0.85	2.04	2.882 (6)	169

Symmetry codes: (ii) −x+1, y−1/2, −z+1/2; (ix) x+1/2, −y+3/2, −z; (x) x−1/2, −y+3/2, −z; (xi) x+1, y, z; (xii) x−1/2, −y+1/2, −z; (xiii) x−1, y, z.

Experimental details

Crystal data
Chemical formula	[Pr₂(C₂O₄)₃(H₂O)₄]
M_r	617.94
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	293
a, b, c (Å)	8.6358 (17), 9.5356 (19), 16.885 (3)
V (Å³)	1390.4 (5)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	7.02
Crystal size (mm)	0.23 × 0.22 × 0.20

Data collection
Diffractometer	Rigaku Mercury CCD
Absorption correction	Multi-scan (CrystalClear; Rigaku, 2002)
T_min, T_max	0.295, 0.334
No. of measured, independent and observed [I > 2σ(I)] reflections	13654, 3181, 2826
R_int	0.047
(sin θ/λ)_max (Å⁻¹)	0.648

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.029, 0.072, 1.04
No. of reflections	3181
No. of parameters	217
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.34, −1.44
Absolute structure	Flack (1983), 1344 Friedel pairs
Absolute structure parameter	0.49 (3)

Computer programs: CrystalClear (Rigaku, 2002), CrystalStructure (Rigaku/MSC, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEPII (Johnson, 1976).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1W···O2ⁱ	0.85	2.02	2.852 (6)	166
O1W—H2W···O8ⁱⁱ	0.85	2.15	2.998 (6)	173
O2W—H3W···O4ⁱⁱⁱ	0.85	2.40	2.998 (6)	128
O2W—H4W···O6^iv	0.85	2.01	2.792 (6)	152
O3W—H5W···O12^v	0.85	1.97	2.780 (6)	158
O3W—H6W···O3^v	0.85	2.60	3.379 (7)	154
O4W—H7W···O1^vi	0.85	2.16	2.865 (6)	140
O4W—H8W···O9^v	0.85	2.04	2.882 (6)	169

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

Acknowledgements

The authors acknowledge Pingdingshan University for supporting this work.

References

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