Bis(μ-3-nitro­benzene-1,2-dicarboxyl­ato)-κ4O1,O2:O1,O1′;κ4O1,O1′:O1,O2-bis­[triaqua­(6-carb­oxy-2-nitro­benzoato-κ2O1,O6)neodymium(III)] dihydrate

Chang, Y.; Pei, Z.; Shuai, Q.

doi:10.1107/S1600536812042754

metal-organic compounds

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ISSN: 2056-9890

Volume 68| Part 11| November 2012| Page m1379

doi:10.1107/S1600536812042754

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Bis(μ-3-nitrobenzene-1,2-dicarboxylato)-κ⁴O¹,O²:O¹,O^1′;κ⁴O¹,O^1′:O¹,O²-bis[triaqua(6-carboxy-2-nitrobenzoato-κ²O¹,O⁶)neodymium(III)] dihydrate

Yin-cheng Chang,^a Zhi-chao Pei ^a ^* and Qi Shuai ^a ^*

^aCollege of Science, Northwest A&F University, Yangling 712100, Shanxi Province, People's Republic of China
^*Correspondence e-mail: peizc@nwsuaf.edu.cn, shuaiqi@nwsuaf.edu.cn

(Received 28 September 2012; accepted 12 October 2012; online 20 October 2012)

The title complex, [Nd₂(C₈H₃NO₆)₂(C₈H₄NO₆)₂(H₂O)₆]·2H₂O, consists of dimeric units related by an inversion center. The Nd^III atom is nine-coordinated by three O atoms from water molecules and six from carboxylate atoms. The 1,2-dicarboxylate acid molecules are in a single and double deprotonation stage and exhibit two coordination modes, viz. μ₂-(κ⁴, O¹: O²: O²: O³) and μ₁-(κ², O²: O³), which are responsible for the dimeric structure framework. The dimeric structure is then assembled into a three-dimensional supramolecular framework via O—H⋯O hydrogen bonds.

Related literature

For the isotypic La compound, see: Xiong & Qi (2007 ).

Experimental

Crystal data

[Nd₂₂(C₈H₃NO₆)₂(C₈H₄NO₆)(H₂O)₆]·2H₂O
M_r = 1271.08
Triclinic, $[P \overline 1]$
a = 8.1460 (7) Å
b = 8.8090 (9) Å
c = 15.1670 (13) Å
α = 100.434 (1)°
β = 91.106 (1)°
γ = 104.482 (2)°
V = 1033.96 (16) Å³
Z = 1
Mo Kα radiation
μ = 2.60 mm⁻¹
T = 298 K
0.16 × 0.14 × 0.10 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2007 ) T_min = 0.681, T_max = 0.781
5316 measured reflections
3618 independent reflections
3196 reflections with I > 2σ(I)
R_int = 0.030

Refinement

R[F² > 2σ(F²)] = 0.033
wR(F²) = 0.076
S = 1.03
3618 reflections
317 parameters
H-atom parameters constrained
Δρ_max = 1.51 e Å⁻³
Δρ_min = −0.88 e Å⁻³

Table 1
Selected bond lengths (Å)

Nd1—O1	2.489 (3)
Nd1—O3	2.447 (3)
Nd1—O7	2.561 (3)
Nd1—O8	2.564 (3)
Nd1—O8ⁱ	2.486 (3)
Nd1—O10ⁱ	2.431 (3)
Nd1—O13	2.554 (3)
Nd1—O14	2.487 (3)
Nd1—O15	2.398 (3)
Symmetry code: (i) -x+1, -y+1, -z+1.

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H2⋯O16ⁱⁱ	0.82	1.79	2.588 (4)	163
O13—H13C⋯O3ⁱ	0.85	2.19	3.026 (5)	169
O13—H13D⋯O10ⁱⁱ	0.85	2.12	2.952 (5)	168
O14—H14B⋯O7ⁱⁱⁱ	0.85	1.98	2.750 (5)	150
O14—H14C⋯O4	0.85	2.00	2.782 (4)	152
O15—H15C⋯O9ⁱⁱ	0.85	1.81	2.654 (4)	177
O15—H15D⋯O16ⁱⁱ	0.85	2.02	2.867 (5)	177
O16—H16C⋯O4	0.85	1.92	2.767 (5)	179
O16—H16D⋯O9^iv	0.85	1.88	2.730 (5)	179
Symmetry codes: (i) -x+1, -y+1, -z+1; (ii) x-1, y, z; (iii) -x+1, -y+2, -z+1; (iv) -x+2, -y+2, -z+1.

Data collection: SMART (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); 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.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812042754/vn2055sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812042754/vn2055Isup2.hkl

checkCIF report

Comment top

We report here a neodymium complex based on 3-nitrobenzene-1,2- dicarboxylic acid ligands. X-ray diffraction crystal structure analysis reveals that the complex forms a structure [Nd₂(C₈H₄NO₆)₂(C₈H₃NO₆)₂ (H₂O)₆].2H₂O, consisting of dimeric units related by an inversion center. The compound is isostructural to the corresponding La compound reported by Xiong & Qi (2007).

In the title complex, the central neodymium center is coordinated by nine oxygen atoms (Fig. 1), the coordination geometry of which can be described as distorted tricapped trigonal-prismatic. Six of the nine coordinating oxygens are from the two coordinating H₂NPA (3-nitrobenzene-1,2-dicarboxylic acid) ligands and the remaining three from water molecules. 3-Nitrobenzene-1,2-dicarboxylic acid ligands exhibit two coordination modes (Fig. 2), which can be classified as µ₂-(κ⁴, O¹: O²: O²: O³) and µ₁-(κ², O²: O³). In one unit of the complex, there are four H₂NPA anions. Two (NPA^2-) ions are dianionic, so the other (HNPA^-) anion is monoprotonated to maintain electroneutrality. Correspondingly, two types of coordination modes of H₂NPA ligands exist in the structure.

Related literature top

For the isotypic La compound, see: Xiong & Qi (2007).

Experimental top

A mixture of neodymium chloride hexahydrate (0.03585 g, 0.1 mmol), sodium hydroxide (0.0080 g, 0.2 mmol), 3-nitrobenzene-1,2-dicarboxylic acid (0.0211 g, 0.1 mmol), and CH₃OH (20 mL) was placed in a Parr Teflon-lined stainless stell vessel (25 ml), which was sealed and heated at 443.15 K for 4 days. Then the vessel was cooled to 373.15 K at a rate of 5 K h^-1 and subsequently slowly to room temperature. Purple, block single crystals suitable for X-ray diffraction were obtained.

Computing details top

Data collection: SMART (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); 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 (Sheldrick, 2008).

Figures top

	Fig. 1. Coordination environment of Nd^III atoms; atoms are shown as 30% probability ellipsoids. Symmetry codes: (A) 1 - x, 1 - y, 1 - z;
	Fig. 2. Coordination modes of 3-Nitrobenzene-1,2-dicarboxylic acid ligands in the title complex. Hydrogen atoms are omitted for clarity.

Bis(µ-3-nitrobenzene-1,2-dicarboxylato)- κ⁴O¹,O²:O¹,O^1'; κ⁴O¹,O^1':O¹,O²-bis[triaqua(6-carboxy-2- nitrobenzoato-κ²O¹,O⁶)neodymium(III)] dihydrate top

Crystal data top

[Nd₂(C₈H₃NO₆)₂(C₈H₄NO₆)₂(H₂O)₆]·2H₂O	Z = 1
M_r = 1271.08	F(000) = 626
Triclinic, P1	D_x = 2.041 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.1460 (7) Å	Cell parameters from 2861 reflections
b = 8.8090 (9) Å	θ = 2.6–27.9°
c = 15.1670 (13) Å	µ = 2.60 mm⁻¹
α = 100.434 (1)°	T = 298 K
β = 91.106 (1)°	Block, purple
γ = 104.482 (2)°	0.16 × 0.14 × 0.10 mm
V = 1033.96 (16) Å³

Data collection top

Bruker SMART CCD area-detector diffractometer	3618 independent reflections
Radiation source: fine-focus sealed tube	3196 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.030
phi and ω scans	θ_max = 25.0°, θ_min = 2.6°
Absorption correction: multi-scan (SADABS; Bruker, 2007)	h = −9→8
T_min = 0.681, T_max = 0.781	k = −10→10
5316 measured reflections	l = −14→18

Refinement top

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)] = 0.033	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.076	H-atom parameters constrained
S = 1.03	w = 1/[σ²(F_o²) + (0.0341P)²] where P = (F_o² + 2F_c²)/3
3618 reflections	(Δ/σ)_max = 0.001
317 parameters	Δρ_max = 1.51 e Å⁻³
0 restraints	Δρ_min = −0.88 e Å⁻³

Crystal data top

[Nd₂(C₈H₃NO₆)₂(C₈H₄NO₆)₂(H₂O)₆]·2H₂O	γ = 104.482 (2)°
M_r = 1271.08	V = 1033.96 (16) Å³
Triclinic, P1	Z = 1
a = 8.1460 (7) Å	Mo Kα radiation
b = 8.8090 (9) Å	µ = 2.60 mm⁻¹
c = 15.1670 (13) Å	T = 298 K
α = 100.434 (1)°	0.16 × 0.14 × 0.10 mm
β = 91.106 (1)°

Data collection top

Bruker SMART CCD area-detector diffractometer	3618 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2007)	3196 reflections with I > 2σ(I)
T_min = 0.681, T_max = 0.781	R_int = 0.030
5316 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.033	0 restraints
wR(F²) = 0.076	H-atom parameters constrained
S = 1.03	Δρ_max = 1.51 e Å⁻³
3618 reflections	Δρ_min = −0.88 e Å⁻³
317 parameters

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
Nd1	0.34954 (3)	0.61211 (3)	0.432565 (17)	0.02109 (10)
N1	0.6299 (5)	0.3586 (5)	0.0945 (3)	0.0357 (11)
N2	1.0429 (5)	0.8971 (5)	0.8325 (3)	0.0338 (10)
O1	0.2534 (4)	0.6797 (4)	0.2912 (2)	0.0323 (8)
O2	0.0666 (4)	0.6809 (4)	0.1849 (2)	0.0387 (9)
H2	0.0399	0.7439	0.2253	0.058*
O3	0.5209 (4)	0.5333 (4)	0.3102 (2)	0.0239 (7)
O4	0.6217 (4)	0.7219 (4)	0.2293 (2)	0.0317 (8)
O5	0.7245 (5)	0.4265 (5)	0.1614 (3)	0.0525 (11)
O6	0.6688 (5)	0.2711 (5)	0.0317 (3)	0.0594 (12)
O7	0.4497 (4)	0.8304 (4)	0.5729 (2)	0.0313 (8)
O8	0.5879 (4)	0.6447 (3)	0.5528 (2)	0.0222 (7)
O9	1.0001 (4)	0.8529 (4)	0.6082 (2)	0.0354 (9)
O10	0.8932 (4)	0.6062 (4)	0.6320 (2)	0.0282 (8)
O11	1.1186 (5)	0.8219 (6)	0.7825 (3)	0.0686 (15)
O12	1.1035 (5)	0.9742 (6)	0.9051 (3)	0.0666 (14)
O13	0.2084 (4)	0.5262 (4)	0.5708 (2)	0.0362 (9)
H13C	0.2752	0.5118	0.6104	0.043*
H13D	0.1227	0.5482	0.5960	0.043*
O14	0.5560 (4)	0.8539 (4)	0.4017 (2)	0.0363 (9)
H14B	0.5211	0.9371	0.4185	0.044*
H14C	0.5732	0.8444	0.3461	0.044*
O15	0.1355 (4)	0.7563 (4)	0.4572 (2)	0.0374 (9)
H15C	0.0946	0.7860	0.5066	0.045*
H15D	0.0798	0.7770	0.4150	0.045*
O16	0.9404 (4)	0.8298 (4)	0.3189 (2)	0.0382 (9)
H16C	0.8423	0.7975	0.2915	0.046*
H16D	0.9577	0.9285	0.3414	0.046*
C1	0.1920 (6)	0.6321 (6)	0.2148 (3)	0.0278 (11)
C2	0.5315 (6)	0.5899 (5)	0.2390 (3)	0.0249 (11)
C3	0.2498 (6)	0.5176 (6)	0.1470 (3)	0.0264 (11)
C4	0.4139 (6)	0.4937 (5)	0.1582 (3)	0.0244 (11)
C5	0.4606 (6)	0.3880 (5)	0.0893 (3)	0.0292 (11)
C6	0.3539 (7)	0.3078 (6)	0.0136 (4)	0.0395 (14)
H6	0.3899	0.2386	−0.0312	0.047*
C7	0.1944 (7)	0.3323 (6)	0.0059 (4)	0.0397 (14)
H7	0.1217	0.2795	−0.0444	0.048*
C8	0.1426 (7)	0.4342 (6)	0.0721 (3)	0.0334 (12)
H8	0.0335	0.4480	0.0669	0.040*
C9	0.5563 (6)	0.7666 (5)	0.6009 (3)	0.0225 (10)
C10	0.9095 (6)	0.7554 (6)	0.6468 (3)	0.0258 (11)
C11	0.6390 (6)	0.8337 (5)	0.6931 (3)	0.0221 (10)
C12	0.8033 (6)	0.8239 (5)	0.7179 (3)	0.0208 (10)
C13	0.8675 (6)	0.8954 (5)	0.8048 (3)	0.0244 (11)
C14	0.7784 (6)	0.9698 (6)	0.8671 (3)	0.0314 (12)
H14	0.8264	1.0151	0.9250	0.038*
C15	0.6166 (7)	0.9762 (6)	0.8425 (4)	0.0354 (13)
H15	0.5539	1.0254	0.8838	0.042*
C16	0.5485 (6)	0.9089 (5)	0.7558 (3)	0.0271 (11)
H16	0.4399	0.9141	0.7391	0.032*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Nd1	0.02379 (15)	0.02005 (14)	0.01938 (16)	0.00804 (10)	−0.00171 (10)	0.00071 (11)
N1	0.037 (3)	0.030 (2)	0.040 (3)	0.009 (2)	0.014 (2)	0.002 (2)
N2	0.033 (3)	0.031 (2)	0.032 (3)	0.005 (2)	−0.009 (2)	−0.002 (2)
O1	0.038 (2)	0.045 (2)	0.0184 (19)	0.0203 (17)	−0.0029 (15)	0.0049 (17)
O2	0.038 (2)	0.046 (2)	0.034 (2)	0.0232 (18)	−0.0095 (17)	−0.0026 (18)
O3	0.0257 (18)	0.0293 (17)	0.0194 (18)	0.0123 (14)	0.0027 (14)	0.0043 (15)
O4	0.0310 (19)	0.0286 (18)	0.032 (2)	0.0014 (15)	0.0011 (15)	0.0071 (16)
O5	0.040 (2)	0.063 (3)	0.053 (3)	0.025 (2)	−0.002 (2)	−0.009 (2)
O6	0.060 (3)	0.069 (3)	0.048 (3)	0.031 (2)	0.017 (2)	−0.013 (2)
O7	0.037 (2)	0.0268 (17)	0.031 (2)	0.0167 (15)	−0.0086 (16)	−0.0019 (16)
O8	0.0302 (18)	0.0204 (16)	0.0161 (17)	0.0115 (14)	−0.0017 (13)	−0.0032 (14)
O9	0.039 (2)	0.0296 (18)	0.037 (2)	0.0069 (16)	0.0173 (17)	0.0048 (17)
O10	0.0263 (18)	0.0225 (17)	0.033 (2)	0.0081 (14)	−0.0031 (15)	−0.0031 (15)
O11	0.045 (3)	0.101 (4)	0.056 (3)	0.039 (3)	−0.016 (2)	−0.020 (3)
O12	0.056 (3)	0.078 (3)	0.052 (3)	0.025 (2)	−0.032 (2)	−0.029 (3)
O13	0.031 (2)	0.050 (2)	0.034 (2)	0.0165 (17)	0.0089 (16)	0.0136 (18)
O14	0.047 (2)	0.0233 (17)	0.039 (2)	0.0116 (16)	0.0102 (17)	0.0047 (16)
O15	0.047 (2)	0.051 (2)	0.024 (2)	0.0328 (19)	0.0043 (16)	0.0055 (18)
O16	0.042 (2)	0.0252 (18)	0.046 (2)	0.0133 (16)	−0.0067 (18)	−0.0017 (17)
C1	0.027 (3)	0.029 (3)	0.028 (3)	0.008 (2)	0.002 (2)	0.009 (2)
C2	0.024 (3)	0.028 (3)	0.023 (3)	0.013 (2)	0.003 (2)	−0.003 (2)
C3	0.028 (3)	0.030 (3)	0.023 (3)	0.007 (2)	0.000 (2)	0.009 (2)
C4	0.027 (3)	0.024 (2)	0.022 (3)	0.005 (2)	0.003 (2)	0.006 (2)
C5	0.039 (3)	0.024 (2)	0.026 (3)	0.008 (2)	0.005 (2)	0.009 (2)
C6	0.061 (4)	0.030 (3)	0.024 (3)	0.008 (3)	0.003 (3)	−0.001 (2)
C7	0.049 (4)	0.037 (3)	0.027 (3)	0.006 (3)	−0.015 (3)	0.000 (3)
C8	0.041 (3)	0.030 (3)	0.029 (3)	0.011 (2)	−0.011 (2)	0.003 (2)
C9	0.022 (2)	0.022 (2)	0.021 (3)	0.002 (2)	0.001 (2)	0.002 (2)
C10	0.022 (3)	0.031 (3)	0.021 (3)	0.010 (2)	−0.005 (2)	−0.005 (2)
C11	0.026 (3)	0.020 (2)	0.020 (3)	0.0053 (19)	0.002 (2)	0.002 (2)
C12	0.024 (2)	0.017 (2)	0.019 (3)	0.0029 (19)	−0.0009 (19)	0.001 (2)
C13	0.030 (3)	0.019 (2)	0.023 (3)	0.006 (2)	−0.001 (2)	0.001 (2)
C14	0.041 (3)	0.030 (3)	0.017 (3)	0.004 (2)	0.001 (2)	−0.002 (2)
C15	0.047 (3)	0.029 (3)	0.028 (3)	0.013 (2)	0.010 (2)	−0.004 (2)
C16	0.026 (3)	0.026 (2)	0.029 (3)	0.011 (2)	0.004 (2)	0.000 (2)

Geometric parameters (Å, º) top

Nd1—O1	2.489 (3)	O14—H14B	0.8500
Nd1—O3	2.447 (3)	O14—H14C	0.8500
Nd1—O7	2.561 (3)	O15—H15C	0.8500
Nd1—O8	2.564 (3)	O15—H15D	0.8500
Nd1—O8ⁱ	2.486 (3)	O16—H16C	0.8500
Nd1—O10ⁱ	2.431 (3)	O16—H16D	0.8499
Nd1—O13	2.554 (3)	C1—C3	1.475 (7)
Nd1—O14	2.487 (3)	C2—C4	1.520 (6)
Nd1—O15	2.398 (3)	C3—C8	1.390 (6)
N1—O6	1.212 (5)	C3—C4	1.416 (6)
N1—O5	1.225 (6)	C4—C5	1.394 (7)
N1—C5	1.469 (6)	C5—C6	1.391 (7)
N2—O11	1.197 (6)	C6—C7	1.376 (8)
N2—O12	1.208 (5)	C6—H6	0.9300
N2—C13	1.477 (6)	C7—C8	1.368 (7)
O1—C1	1.211 (6)	C7—H7	0.9300
O2—C1	1.306 (6)	C8—H8	0.9300
O2—H2	0.8200	C9—C11	1.491 (6)
O3—C2	1.265 (6)	C10—C12	1.528 (6)
O4—C2	1.246 (5)	C11—C16	1.389 (6)
O7—C9	1.252 (5)	C11—C12	1.411 (6)
O8—C9	1.270 (5)	C12—C13	1.384 (6)
O8—Nd1ⁱ	2.486 (3)	C13—C14	1.375 (7)
O9—C10	1.228 (6)	C14—C15	1.381 (7)
O10—C10	1.265 (5)	C14—H14	0.9300
O10—Nd1ⁱ	2.431 (3)	C15—C16	1.383 (7)
O13—H13C	0.8500	C15—H15	0.9300
O13—H13D	0.8500	C16—H16	0.9300

O15—Nd1—O10ⁱ	82.46 (11)	Nd1—O14—H14C	111.0
O15—Nd1—O3	137.86 (11)	H14B—O14—H14C	109.2
O10ⁱ—Nd1—O3	90.90 (11)	Nd1—O15—H15C	127.9
O15—Nd1—O8ⁱ	142.35 (11)	Nd1—O15—H15D	123.5
O10ⁱ—Nd1—O8ⁱ	71.22 (10)	H15C—O15—H15D	108.3
O3—Nd1—O8ⁱ	70.52 (10)	H16C—O16—H16D	108.4
O15—Nd1—O14	90.69 (12)	O1—C1—O2	121.7 (5)
O10ⁱ—Nd1—O14	143.71 (12)	O1—C1—C3	124.5 (4)
O3—Nd1—O14	70.66 (11)	O2—C1—C3	113.8 (4)
O8ⁱ—Nd1—O14	126.35 (11)	O4—C2—O3	126.7 (4)
O15—Nd1—O1	68.22 (11)	O4—C2—C4	115.8 (4)
O10ⁱ—Nd1—O1	73.83 (11)	O3—C2—C4	117.3 (4)
O3—Nd1—O1	69.96 (10)	C8—C3—C4	120.4 (5)
O8ⁱ—Nd1—O1	125.78 (10)	C8—C3—C1	119.6 (4)
O14—Nd1—O1	70.56 (12)	C4—C3—C1	120.1 (4)
O15—Nd1—O13	75.73 (11)	C5—C4—C3	116.2 (4)
O10ⁱ—Nd1—O13	76.95 (11)	C5—C4—C2	124.1 (4)
O3—Nd1—O13	143.02 (11)	C3—C4—C2	119.6 (4)
O8ⁱ—Nd1—O13	72.49 (10)	C6—C5—C4	123.0 (5)
O14—Nd1—O13	135.72 (11)	C6—C5—N1	117.1 (5)
O1—Nd1—O13	135.80 (11)	C4—C5—N1	119.9 (4)
O15—Nd1—O7	72.57 (11)	C7—C6—C5	119.0 (5)
O10ⁱ—Nd1—O7	141.54 (11)	C7—C6—H6	120.5
O3—Nd1—O7	127.18 (11)	C5—C6—H6	120.5
O8ⁱ—Nd1—O7	112.88 (10)	C8—C7—C6	120.1 (5)
O14—Nd1—O7	66.79 (11)	C8—C7—H7	120.0
O1—Nd1—O7	120.33 (11)	C6—C7—H7	120.0
O13—Nd1—O7	68.93 (11)	C7—C8—C3	121.3 (5)
O15—Nd1—O8	121.59 (10)	C7—C8—H8	119.4
O10ⁱ—Nd1—O8	133.76 (10)	C3—C8—H8	119.4
O3—Nd1—O8	92.65 (10)	O7—C9—O8	120.4 (4)
O8ⁱ—Nd1—O8	66.76 (11)	O7—C9—C11	118.2 (4)
O14—Nd1—O8	79.62 (11)	O8—C9—C11	121.4 (4)
O1—Nd1—O8	149.00 (11)	O9—C10—O10	126.6 (4)
O13—Nd1—O8	72.89 (11)	O9—C10—C12	115.4 (4)
O7—Nd1—O8	50.55 (9)	O10—C10—C12	117.9 (4)
O6—N1—O5	124.0 (5)	C16—C11—C12	119.8 (4)
O6—N1—C5	118.1 (5)	C16—C11—C9	117.6 (4)
O5—N1—C5	117.9 (4)	C12—C11—C9	122.6 (4)
O11—N2—O12	122.9 (5)	C13—C12—C11	116.8 (4)
O11—N2—C13	118.9 (4)	C13—C12—C10	122.9 (4)
O12—N2—C13	118.2 (4)	C11—C12—C10	119.8 (4)
C1—O1—Nd1	147.6 (3)	C14—C13—C12	123.6 (4)
C1—O2—H2	109.5	C14—C13—N2	117.4 (4)
C2—O3—Nd1	122.9 (3)	C12—C13—N2	119.0 (4)
C9—O7—Nd1	94.6 (3)	C13—C14—C15	119.0 (5)
C9—O8—Nd1ⁱ	140.4 (3)	C13—C14—H14	120.5
C9—O8—Nd1	94.0 (3)	C15—C14—H14	120.5
Nd1ⁱ—O8—Nd1	113.24 (11)	C14—C15—C16	119.4 (5)
C10—O10—Nd1ⁱ	129.9 (3)	C14—C15—H15	120.3
Nd1—O13—H13C	115.0	C16—C15—H15	120.3
Nd1—O13—H13D	130.1	C15—C16—C11	121.4 (5)
H13C—O13—H13D	108.7	C15—C16—H16	119.3
Nd1—O14—H14B	111.1	C11—C16—H16	119.3

O15—Nd1—O1—C1	−122.1 (6)	O4—C2—C4—C5	88.0 (6)
O10ⁱ—Nd1—O1—C1	−33.8 (6)	O3—C2—C4—C5	−96.1 (6)
O3—Nd1—O1—C1	63.2 (6)	O4—C2—C4—C3	−87.7 (5)
O8ⁱ—Nd1—O1—C1	17.7 (6)	O3—C2—C4—C3	88.2 (5)
O14—Nd1—O1—C1	139.0 (6)	C3—C4—C5—C6	−0.6 (7)
O13—Nd1—O1—C1	−84.4 (6)	C2—C4—C5—C6	−176.4 (5)
O7—Nd1—O1—C1	−174.6 (6)	C3—C4—C5—N1	178.8 (4)
O8—Nd1—O1—C1	122.5 (6)	C2—C4—C5—N1	3.0 (7)
O15—Nd1—O3—C2	12.2 (4)	O6—N1—C5—C6	2.4 (7)
O10ⁱ—Nd1—O3—C2	91.9 (3)	O5—N1—C5—C6	−179.0 (5)
O8ⁱ—Nd1—O3—C2	161.6 (3)	O6—N1—C5—C4	−177.0 (5)
O14—Nd1—O3—C2	−56.2 (3)	O5—N1—C5—C4	1.6 (7)
O1—Nd1—O3—C2	19.5 (3)	C4—C5—C6—C7	−0.4 (8)
O13—Nd1—O3—C2	161.1 (3)	N1—C5—C6—C7	−179.8 (5)
O7—Nd1—O3—C2	−94.0 (3)	C5—C6—C7—C8	0.0 (8)
O8—Nd1—O3—C2	−134.2 (3)	C6—C7—C8—C3	1.5 (8)
O15—Nd1—O7—C9	161.9 (3)	C4—C3—C8—C7	−2.5 (8)
O10ⁱ—Nd1—O7—C9	109.9 (3)	C1—C3—C8—C7	177.1 (5)
O3—Nd1—O7—C9	−60.6 (3)	Nd1—O7—C9—O8	7.1 (4)
O8ⁱ—Nd1—O7—C9	21.7 (3)	Nd1—O7—C9—C11	−170.4 (3)
O14—Nd1—O7—C9	−99.6 (3)	Nd1ⁱ—O8—C9—O7	−141.9 (4)
O1—Nd1—O7—C9	−147.5 (3)	Nd1—O8—C9—O7	−7.1 (4)
O13—Nd1—O7—C9	80.8 (3)	Nd1ⁱ—O8—C9—C11	35.6 (7)
O8—Nd1—O7—C9	−3.9 (2)	Nd1—O8—C9—C11	170.4 (4)
O15—Nd1—O8—C9	−12.1 (3)	Nd1ⁱ—O10—C10—O9	−111.5 (5)
O10ⁱ—Nd1—O8—C9	−124.2 (3)	Nd1ⁱ—O10—C10—C12	66.6 (5)
O3—Nd1—O8—C9	142.1 (3)	O7—C9—C11—C16	27.8 (6)
O8ⁱ—Nd1—O8—C9	−150.5 (3)	O8—C9—C11—C16	−149.7 (4)
O14—Nd1—O8—C9	72.3 (3)	O7—C9—C11—C12	−151.8 (4)
O1—Nd1—O8—C9	88.1 (3)	O8—C9—C11—C12	30.7 (7)
O13—Nd1—O8—C9	−72.6 (3)	C16—C11—C12—C13	−1.6 (6)
O7—Nd1—O8—C9	3.9 (2)	C9—C11—C12—C13	178.0 (4)
O15—Nd1—O8—Nd1ⁱ	138.38 (13)	C16—C11—C12—C10	−174.2 (4)
O10ⁱ—Nd1—O8—Nd1ⁱ	26.3 (2)	C9—C11—C12—C10	5.4 (7)
O3—Nd1—O8—Nd1ⁱ	−67.47 (13)	O9—C10—C12—C13	−82.4 (6)
O8ⁱ—Nd1—O8—Nd1ⁱ	0.0	O10—C10—C12—C13	99.3 (5)
O14—Nd1—O8—Nd1ⁱ	−137.26 (14)	O9—C10—C12—C11	89.8 (5)
O1—Nd1—O8—Nd1ⁱ	−121.39 (18)	O10—C10—C12—C11	−88.6 (5)
O13—Nd1—O8—Nd1ⁱ	77.86 (13)	C11—C12—C13—C14	1.8 (7)
O7—Nd1—O8—Nd1ⁱ	154.34 (19)	C10—C12—C13—C14	174.1 (5)
Nd1—O1—C1—O2	131.8 (5)	C11—C12—C13—N2	−176.4 (4)
Nd1—O1—C1—C3	−48.8 (9)	C10—C12—C13—N2	−4.0 (7)
Nd1—O3—C2—O4	79.5 (5)	O11—N2—C13—C14	173.7 (5)
Nd1—O3—C2—C4	−95.9 (4)	O12—N2—C13—C14	−6.0 (7)
O1—C1—C3—C8	160.5 (5)	O11—N2—C13—C12	−8.0 (7)
O2—C1—C3—C8	−20.1 (7)	O12—N2—C13—C12	172.3 (5)
O1—C1—C3—C4	−19.9 (7)	C12—C13—C14—C15	−0.8 (8)
O2—C1—C3—C4	159.5 (4)	N2—C13—C14—C15	177.4 (4)
C8—C3—C4—C5	2.0 (7)	C13—C14—C15—C16	−0.4 (8)
C1—C3—C4—C5	−177.6 (4)	C14—C15—C16—C11	0.5 (8)
C8—C3—C4—C2	178.0 (4)	C12—C11—C16—C15	0.5 (7)
C1—C3—C4—C2	−1.6 (7)	C9—C11—C16—C15	−179.1 (4)

Symmetry code: (i) −x+1, −y+1, −z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···O16ⁱⁱ	0.82	1.79	2.588 (4)	163
O13—H13C···O3ⁱ	0.85	2.19	3.026 (5)	169
O13—H13D···O10ⁱⁱ	0.85	2.12	2.952 (5)	168
O14—H14B···O7ⁱⁱⁱ	0.85	1.98	2.750 (5)	150
O14—H14C···O4	0.85	2.00	2.782 (4)	152
O15—H15C···O9ⁱⁱ	0.85	1.81	2.654 (4)	177
O15—H15D···O16ⁱⁱ	0.85	2.02	2.867 (5)	177
O16—H16C···O4	0.85	1.92	2.767 (5)	179
O16—H16D···O9^iv	0.85	1.88	2.730 (5)	179

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

Experimental details

Crystal data
Chemical formula	[Nd₂(C₈H₃NO₆)₂(C₈H₄NO₆)₂(H₂O)₆]·2H₂O
M_r	1271.08
Crystal system, space group	Triclinic, P1
Temperature (K)	298
a, b, c (Å)	8.1460 (7), 8.8090 (9), 15.1670 (13)
α, β, γ (°)	100.434 (1), 91.106 (1), 104.482 (2)
V (Å³)	1033.96 (16)
Z	1
Radiation type	Mo Kα
µ (mm⁻¹)	2.60
Crystal size (mm)	0.16 × 0.14 × 0.10

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2007)
T_min, T_max	0.681, 0.781
No. of measured, independent and observed [I > 2σ(I)] reflections	5316, 3618, 3196
R_int	0.030
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.033, 0.076, 1.03
No. of reflections	3618
No. of parameters	317
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.51, −0.88

Computer programs: SMART (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Selected bond lengths (Å) top

Nd1—O1	2.489 (3)	Nd1—O10ⁱ	2.431 (3)
Nd1—O3	2.447 (3)	Nd1—O13	2.554 (3)
Nd1—O7	2.561 (3)	Nd1—O14	2.487 (3)
Nd1—O8	2.564 (3)	Nd1—O15	2.398 (3)
Nd1—O8ⁱ	2.486 (3)

Symmetry code: (i) −x+1, −y+1, −z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···O16ⁱⁱ	0.820	1.792	2.588 (4)	163.03
O13—H13C···O3ⁱ	0.850	2.189	3.026 (5)	168.45
O13—H13D···O10ⁱⁱ	0.850	2.115	2.952 (5)	168.24
O14—H14B···O7ⁱⁱⁱ	0.850	1.981	2.750 (5)	149.89
O14—H14C···O4	0.850	2.001	2.782 (4)	152.21
O15—H15C···O9ⁱⁱ	0.850	1.805	2.654 (4)	177.03
O15—H15D···O16ⁱⁱ	0.850	2.018	2.867 (5)	177.39
O16—H16C···O4	0.850	1.917	2.767 (5)	179.19
O16—H16D···O9^iv	0.850	1.880	2.730 (5)	179.00

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

Acknowledgements

This work was supported by the National Natural Science Foundation of China (grant No. 21103140) and the PhD Programs Foundation of the Ministry of Education of China (No. 20110204120037)

References

Bruker (2007). SADABS, SAINT and SMART. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Xiong, L.-Q. & Qi, C.-M. (2007). Acta Cryst. C63, m10–m12. Web of Science CSD CrossRef IUCr Journals Google Scholar

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