(μ-6-Oxido-4-oxo-1,2-dihydro­pyrimidine-5-carboxyl­ato-κ4O5,O6:O2,N3)bis­[aquabis­(4-oxido-2-oxo-1,2-dihydro­pyrimidin-3-ium-5-carboxyl­ato-κ2O4,O5)­(1,10-phenanthroline-κ2N,N′)neodymium(III)] hexa­hydrate

Xing, H.-H.; Chen, Z.-L.; Ng, S.W.

doi:10.1107/S1600536808001499

metal-organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 64| Part 2| February 2008| Pages m419-m420

doi:10.1107/S1600536808001499

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(μ-6-Oxido-4-oxo-1,2-dihydropyrimidine-5-carboxylato-κ⁴O⁵,O⁶:O²,N³)bis[aquabis(4-oxido-2-oxo-1,2-dihydropyrimidin-3-ium-5-carboxylato-κ²O⁴,O⁵)(1,10-phenanthroline-κ²N,N′)neodymium(III)] hexahydrate

Hui-Hui Xing,^a Zi-Lu Chen ^a and Seik Weng Ng ^b ^*

^aCollege of Chemistry and Chemical Engineering, Guangxi Normal University, Gulin 541004, People's Republic of China, and ^bDepartment of Chemistry, University of Malaya, 50603, Kuala Lumpur, Malaysia
^*Correspondence e-mail: seikweng@um.edu.my

(Received 7 January 2008; accepted 15 January 2008; online 25 January 2008)

The water-coordinated neodymium(III) atom in the centrosymmetric title compound, [Nd₂(C₅H₂N₂O₄)(C₅H₃N₂O₄)₄(C₁₂H₈N₂)₂(H₂O)₂]·6H₂O is chelated by a 1,10-phenanthroline heterocycle and two 2,4-dihydroxypyrimidine-5-carboxylate dianions. Two tris-chelated water-coordinated units are bridged by a 2,4-dihydroxypyrimidine-5-carboxylate dianion, which is disordered about a center of inversion. The metal center has a monocapped square-antiprismatic coordination.

Related literature

The title neodymium compound is isostructural with the praseodymium analog (Sun & Jin, 2004 ). For a related structure, see: Xing et al. (2008 ).

Experimental

Crystal data

[Nd₂(C₅H₂N₂O₄)(C₅H₃N₂O₄)₄(C₁₂H₈N₂)₂(H₂O)₂]·6H₂O
M_r = 1567.48
Triclinic, $[P \overline 1]$
a = 10.1980 (7) Å
b = 12.8896 (9) Å
c = 13.3383 (9) Å
α = 118.711 (1)°
β = 90.010 (1)°
γ = 108.612 (1)°
V = 1432.25 (17) Å³
Z = 1
Mo Kα radiation
μ = 1.90 mm⁻¹
T = 295 (2) K
0.10 × 0.04 × 0.02 mm

Data collection

Bruker APEXII diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.724, T_max = 0.963
12405 measured reflections
6377 independent reflections
5349 reflections with I > 2σ(I)
R_int = 0.039

Refinement

R[F² > 2σ(F²)] = 0.054
wR(F²) = 0.136
S = 1.04
6377 reflections
454 parameters
84 restraints
H-atom parameters constrained
Δρ_max = 1.23 e Å⁻³
Δρ_min = −0.90 e Å⁻³

Table 1
Selected geometric parameters (Å, °)

Nd1—O2	2.526 (4)
Nd1—O3	2.502 (9)
Nd1—O5	2.392 (4)
Nd1—O6	2.575 (4)
Nd1—O9	2.341 (4)
Nd1—O10	2.526 (4)
Nd1—O1W	2.475 (4)
Nd1—N7	2.638 (5)
Nd1—N8	2.725 (5)

O2—Nd1—O3	67.5 (2)
O2—Nd1—O5	71.6 (1)
O2—Nd1—O6	123.5 (1)
O2—Nd1—O9	127.7 (1)
O2—Nd1—O10	71.8 (1)
O2—Nd1—O1W	136.6 (2)
O2—Nd1—N7	70.6 (2)
O2—Nd1—N8	111.7 (2)
O3—Nd1—O5	138.7 (2)
O3—Nd1—O6	133.6 (3)
O3—Nd1—O9	68.6 (3)
O3—Nd1—O10	76.5 (3)
O3—Nd1—O1W	138.2 (3)
O3—Nd1—N7	87.9 (3)
O3—Nd1—N8	65.6 (3)
O5—Nd1—O6	67.9 (1)
O5—Nd1—O9	139.7 (2)
O5—Nd1—O10	85.9 (1)
O5—Nd1—O1W	78.2 (2)
O5—Nd1—N7	83.8 (2)
O5—Nd1—N8	138.8 (2)
O6—Nd1—O9	72.6 (1)
O6—Nd1—O10	67.7 (1)
O6—Nd1—O1W	69.0 (1)
O6—Nd1—N7	138.2 (2)
O6—Nd1—N8	124.8 (2)
O9—Nd1—O10	71.5 (1)
O9—Nd1—O1W	95.5 (2)
O9—Nd1—N7	133.8 (2)
O9—Nd1—N8	72.8 (2)
O10—Nd1—O1W	136.7 (2)
O10—Nd1—N7	142.5 (2)
O10—Nd1—N8	135.1 (2)
O1W—Nd1—N7	75.78 (16)
O1W—Nd1—N8	72.93 (16)
N7—Nd1—N8	61.14 (16)

Data collection: APEX2 (Bruker, 2006 ); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT; method used to solve structure: atomic coordinates taken from the Pr analog (Sun & Jin, 2004); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: X-SEED (Barbour, 2001 ); software used to prepare material for publication: publCIF (Westrip, 2008 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808001499/ci2552sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808001499/ci2552Isup2.hkl

checkCIF report

Comment top

The 1,10-phenanthroline-chelated rare-earth compound, Pr₂(C₁₂H₈N₂)₂(C₅H₂N₂O₄)(C₅H₃N₂O₄)₄(H₂O)₂– ^.3H₂O, represents the first example of dinculear lanthanum derivatives of 2,4-dihydroxpyrimidine-5-carboxylic acid (Sun & Jin, 2004). The present neodymium compound is isostructural with the praseodymium analog.

Related literature top

The title neodymium compound is isostructural with the praesodymium analog (Sun & Jin, 2004). For a related structure, see: Xing et al. (2008).

Experimental top

2,4-Dihydroxypyrimidine-5-carboxylic acid (0.044 g, 0.25 mmol), neodymium trichloride hexahydrate (0.090 g, 0.25 mmol), 1,10-phenanthroline (0.050 g, 0.25 mmol), sodium hydroxide (0.010 g, 0.25 mmol) and water (15 ml) was sealed in a 25-ml, Teflon-lined, stainless-steel Parr bomb. The bomb was heated to 383 K for 120 h. It was then cooled over 48 h to give lilac crystals in 70% yield. CH&N elemental analysis. Found (Calculated) for C₄₉H₄₆N₁₄O₂₈Nd₂: C 37.37, H 3.07, N 12.62% (37.54, 2.96, 12.51%).

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); program(s) used to solve structure: atomic coordinates taken from the Pr analog (Sun & Jin, 2004); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2008).

Figures top

	Fig. 1. Displacement ellipsoid plot of Nd₂(C₁₂H₈N₂)₂(C₅H₂N₂O₄)(C₅H₃N₂O₄)₄(H₂O)₂ ^.6H₂O drawn at the 50% probability level. Unlabelled atoms are related to labelled atoms by the symmetry operation (1 - x, 1 - y, 1 - z). Lattice water molecules have been omitted for clarity. Only one disorder component is shown.
	Fig. 2. Geometry of Nd.

(µ-6-Oxido-4-oxo-1,2-dihydropyrimidine-5-carboxylato- κ⁴O⁵,O⁶:O²,N³)bis[aquabis(4-oxido- 2-oxo-1,2-dihydropyrimidin-3-ium-5-carboxylato- κ²O⁴,O⁵)(1,10-phenanthroline- κ²N,N')neodymium(III)] hexahydrate top

Crystal data top

[Nd₂(C₅H₂N₂O₄)(C₅H₃N₂O₄)₄(C₁₂H₈N₂)₂(H₂O)₂]·6H₂O	Z = 1
M_r = 1567.48	F(000) = 782
Triclinic, P1	D_x = 1.817 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 10.1980 (7) Å	Cell parameters from 2901 reflections
b = 12.8896 (9) Å	θ = 2.3–22.7°
c = 13.3383 (9) Å	µ = 1.90 mm⁻¹
α = 118.711 (1)°	T = 295 K
β = 90.010 (1)°	Prism, lilac
γ = 108.612 (1)°	0.10 × 0.04 × 0.02 mm
V = 1432.25 (17) Å³

Data collection top

Bruker APEXII diffractometer	6377 independent reflections
Radiation source: fine-focus sealed tube	5349 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.039
ϕ and ω scans	θ_max = 27.5°, θ_min = 1.8°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −13→13
T_min = 0.724, T_max = 0.963	k = −16→16
12405 measured reflections	l = −17→17

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)] = 0.054	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.136	H-atom parameters constrained
S = 1.04	w = 1/[σ²(F_o²) + (0.0735P)² + 0.4633P] where P = (F_o² + 2F_c²)/3
6377 reflections	(Δ/σ)_max = 0.001
454 parameters	Δρ_max = 1.23 e Å⁻³
84 restraints	Δρ_min = −0.90 e Å⁻³

Crystal data top

[Nd₂(C₅H₂N₂O₄)(C₅H₃N₂O₄)₄(C₁₂H₈N₂)₂(H₂O)₂]·6H₂O	γ = 108.612 (1)°
M_r = 1567.48	V = 1432.25 (17) Å³
Triclinic, P1	Z = 1
a = 10.1980 (7) Å	Mo Kα radiation
b = 12.8896 (9) Å	µ = 1.90 mm⁻¹
c = 13.3383 (9) Å	T = 295 K
α = 118.711 (1)°	0.10 × 0.04 × 0.02 mm
β = 90.010 (1)°

Data collection top

Bruker APEXII diffractometer	6377 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	5349 reflections with I > 2σ(I)
T_min = 0.724, T_max = 0.963	R_int = 0.039
12405 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.054	84 restraints
wR(F²) = 0.136	H-atom parameters constrained
S = 1.04	Δρ_max = 1.23 e Å⁻³
6377 reflections	Δρ_min = −0.90 e Å⁻³
454 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
Nd1	0.26520 (3)	0.27712 (3)	0.14686 (3)	0.02555 (12)
O4	0.2306 (5)	−0.1369 (4)	−0.0511 (5)	0.0486 (12)
O5	0.2203 (5)	0.0542 (4)	0.0456 (4)	0.0400 (11)
O6	0.3131 (5)	0.1959 (4)	−0.0621 (4)	0.0349 (10)
O7	0.6565 (7)	0.1207 (7)	−0.2689 (7)	0.090 (2)
O8	0.5206 (5)	0.6553 (4)	0.2061 (5)	0.0490 (13)
O9	0.3726 (4)	0.4550 (4)	0.1277 (4)	0.0370 (10)
O10	0.5209 (4)	0.3057 (4)	0.1378 (4)	0.0334 (9)
O11	0.9276 (5)	0.3690 (5)	0.0047 (5)	0.0535 (14)
O1W	0.0466 (5)	0.1916 (4)	0.0068 (4)	0.0442 (11)
H1W1	−0.0305	0.1557	0.0212	0.066*
H1W2	0.0389	0.2526	0.0013	0.066*
O2W	−0.0203 (12)	0.1690 (10)	−0.2139 (10)	0.156 (4)
O3W	0.212 (2)	0.192 (2)	−0.3809 (18)	0.149 (5)	0.50
O4W	0.483 (2)	0.789 (2)	0.4468 (18)	0.155 (5)	0.50
O3'	0.144 (2)	−0.0260 (19)	−0.5588 (18)	0.149 (5)	0.50
O4'	0.418 (2)	0.918 (2)	0.4944 (18)	0.155 (5)	0.50
N3	0.5421 (7)	−0.0189 (6)	−0.2106 (6)	0.0512 (16)
H3N	0.5912	−0.0654	−0.2433	0.061*
N4	0.4768 (6)	0.1499 (5)	−0.1699 (5)	0.0415 (13)
H4N	0.4830	0.2124	−0.1797	0.050*
N5	0.8306 (5)	0.5190 (5)	0.0582 (5)	0.0373 (13)
H5N	0.8986	0.5647	0.0416	0.045*
N6	0.7237 (5)	0.3425 (5)	0.0743 (5)	0.0325 (11)
H6N	0.7251	0.2736	0.0689	0.039*
N7	0.0616 (5)	0.2175 (5)	0.2535 (5)	0.0359 (12)
N8	0.1220 (6)	0.4365 (5)	0.2479 (5)	0.0404 (13)
C6	0.2655 (6)	−0.0264 (6)	−0.0300 (5)	0.0302 (13)
C7	0.3654 (6)	0.0150 (5)	−0.0962 (5)	0.0282 (12)
C8	0.3800 (6)	0.1251 (5)	−0.1048 (5)	0.0291 (12)
C9	0.5642 (8)	0.0857 (8)	−0.2206 (7)	0.053 (2)
C10	0.4462 (7)	−0.0521 (6)	−0.1512 (6)	0.0386 (15)
H10	0.4356	−0.1249	−0.1482	0.046*
C11	0.4953 (7)	0.5402 (6)	0.1568 (5)	0.0319 (13)
C12	0.6137 (6)	0.4941 (5)	0.1250 (5)	0.0300 (13)
C13	0.6123 (6)	0.3775 (5)	0.1135 (5)	0.0279 (12)
C14	0.8335 (6)	0.4081 (6)	0.0429 (6)	0.0379 (15)
C15	0.7258 (6)	0.5607 (6)	0.0983 (5)	0.0338 (14)
H15	0.7303	0.6383	0.1081	0.041*
C16	0.0321 (8)	0.1146 (7)	0.2595 (6)	0.0479 (17)
H16	0.0852	0.0640	0.2260	0.057*
C17	−0.0746 (8)	0.0765 (8)	0.3131 (7)	0.058 (2)
H17	−0.0915	0.0024	0.3154	0.069*
C18	−0.1540 (8)	0.1494 (9)	0.3626 (7)	0.061 (2)
H18	−0.2255	0.1251	0.3989	0.073*
C19	−0.1288 (7)	0.2575 (8)	0.3586 (6)	0.0489 (18)
C20	−0.0184 (6)	0.2911 (7)	0.3026 (5)	0.0382 (15)
C21	−0.2097 (8)	0.3371 (10)	0.4055 (7)	0.067 (3)
H21	−0.2834	0.3149	0.4410	0.080*
C22	−0.1824 (8)	0.4419 (9)	0.3998 (7)	0.062 (2)
H22	−0.2382	0.4906	0.4299	0.074*
C23	−0.0688 (8)	0.4805 (8)	0.3481 (6)	0.0499 (18)
C24	0.0120 (7)	0.4047 (6)	0.2980 (5)	0.0376 (15)
C25	−0.0328 (9)	0.5927 (8)	0.3471 (7)	0.059 (2)
H25	−0.0849	0.6447	0.3789	0.071*
C26	0.0792 (9)	0.6270 (8)	0.2994 (7)	0.059 (2)
H26	0.1058	0.7036	0.3005	0.071*
C27	0.1537 (8)	0.5466 (7)	0.2491 (7)	0.0483 (18)
H27	0.2284	0.5700	0.2149	0.058*
O1	0.3919 (11)	0.1911 (9)	0.4221 (9)	0.059 (3)	0.50
O2	0.3542 (4)	0.2234 (4)	0.2860 (4)	0.0383 (10)
O3	0.3932 (12)	0.4700 (9)	0.3390 (8)	0.042 (3)	0.50
C1	0.3988 (6)	0.2642 (7)	0.3854 (7)	0.034 (3)	0.50
C2	0.4626 (9)	0.4027 (5)	0.4640 (6)	0.021 (3)	0.50
C3	0.4558 (9)	0.4923 (6)	0.4366 (5)	0.032 (3)	0.50
N2	0.5211 (9)	0.6211 (6)	0.5170 (6)	0.028 (3)	0.50
H2N	0.5169	0.6766	0.5001	0.034*	0.50
C4	0.5931 (8)	0.6601 (5)	0.6250 (6)	0.033 (3)	0.50
N1	0.5999 (9)	0.5705 (8)	0.6524 (5)	0.033 (3)	0.50
C5	0.5346 (9)	0.4417 (7)	0.5719 (7)	0.040 (3)	0.50
H5	0.5391	0.3817	0.5903	0.048*	0.50

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Nd1	0.02497 (18)	0.02326 (18)	0.03442 (19)	0.01369 (13)	0.01123 (12)	0.01601 (14)
O4	0.057 (3)	0.030 (2)	0.071 (3)	0.022 (2)	0.022 (3)	0.030 (3)
O5	0.051 (3)	0.025 (2)	0.047 (3)	0.015 (2)	0.021 (2)	0.019 (2)
O6	0.048 (3)	0.033 (2)	0.041 (2)	0.027 (2)	0.019 (2)	0.023 (2)
O7	0.103 (5)	0.095 (5)	0.133 (6)	0.066 (4)	0.085 (5)	0.084 (5)
O8	0.059 (3)	0.028 (2)	0.074 (3)	0.024 (2)	0.031 (3)	0.031 (2)
O9	0.038 (2)	0.035 (2)	0.057 (3)	0.026 (2)	0.021 (2)	0.030 (2)
O10	0.030 (2)	0.032 (2)	0.052 (3)	0.0154 (18)	0.0149 (19)	0.029 (2)
O11	0.038 (3)	0.046 (3)	0.100 (4)	0.025 (2)	0.036 (3)	0.048 (3)
O1W	0.035 (2)	0.046 (3)	0.058 (3)	0.021 (2)	0.011 (2)	0.026 (2)
O2W	0.174 (8)	0.147 (7)	0.156 (7)	0.074 (6)	0.026 (6)	0.075 (6)
O3W	0.195 (10)	0.126 (8)	0.143 (8)	0.064 (7)	0.005 (7)	0.077 (7)
O4W	0.177 (10)	0.163 (9)	0.127 (8)	0.035 (7)	0.036 (7)	0.092 (7)
O3'	0.195 (10)	0.126 (8)	0.143 (8)	0.064 (7)	0.005 (7)	0.077 (7)
O4'	0.177 (10)	0.163 (9)	0.127 (8)	0.035 (7)	0.036 (7)	0.092 (7)
N3	0.063 (4)	0.052 (4)	0.070 (4)	0.042 (3)	0.036 (3)	0.041 (3)
N4	0.051 (3)	0.037 (3)	0.057 (4)	0.025 (3)	0.027 (3)	0.034 (3)
N5	0.029 (3)	0.035 (3)	0.064 (4)	0.012 (2)	0.016 (3)	0.036 (3)
N6	0.028 (3)	0.027 (3)	0.053 (3)	0.011 (2)	0.012 (2)	0.027 (3)
N7	0.033 (3)	0.040 (3)	0.040 (3)	0.016 (2)	0.010 (2)	0.023 (3)
N8	0.038 (3)	0.044 (3)	0.045 (3)	0.025 (3)	0.015 (3)	0.021 (3)
C6	0.029 (3)	0.028 (3)	0.037 (3)	0.012 (2)	0.005 (2)	0.018 (3)
C7	0.030 (3)	0.024 (3)	0.031 (3)	0.013 (2)	0.003 (2)	0.013 (3)
C8	0.031 (3)	0.023 (3)	0.032 (3)	0.011 (2)	0.007 (2)	0.013 (3)
C9	0.057 (5)	0.060 (5)	0.067 (5)	0.037 (4)	0.037 (4)	0.040 (4)
C10	0.046 (4)	0.035 (3)	0.046 (4)	0.021 (3)	0.012 (3)	0.024 (3)
C11	0.041 (4)	0.033 (3)	0.038 (3)	0.020 (3)	0.016 (3)	0.026 (3)
C12	0.033 (3)	0.027 (3)	0.036 (3)	0.012 (3)	0.009 (3)	0.019 (3)
C13	0.023 (3)	0.027 (3)	0.035 (3)	0.009 (2)	0.005 (2)	0.017 (3)
C14	0.027 (3)	0.034 (3)	0.061 (4)	0.012 (3)	0.011 (3)	0.030 (3)
C15	0.037 (3)	0.023 (3)	0.045 (4)	0.010 (3)	0.006 (3)	0.020 (3)
C16	0.043 (4)	0.049 (4)	0.053 (4)	0.017 (3)	0.014 (3)	0.027 (4)
C17	0.050 (5)	0.060 (5)	0.063 (5)	0.010 (4)	0.014 (4)	0.038 (4)
C18	0.043 (4)	0.077 (6)	0.057 (5)	0.013 (4)	0.018 (4)	0.036 (5)
C19	0.036 (4)	0.064 (5)	0.035 (4)	0.014 (4)	0.011 (3)	0.019 (4)
C20	0.028 (3)	0.054 (4)	0.030 (3)	0.020 (3)	0.010 (3)	0.016 (3)
C21	0.041 (4)	0.104 (8)	0.054 (5)	0.037 (5)	0.031 (4)	0.032 (5)
C22	0.048 (5)	0.086 (7)	0.061 (5)	0.044 (5)	0.026 (4)	0.031 (5)
C23	0.047 (4)	0.058 (5)	0.041 (4)	0.031 (4)	0.009 (3)	0.015 (4)
C24	0.035 (3)	0.047 (4)	0.032 (3)	0.027 (3)	0.010 (3)	0.014 (3)
C25	0.063 (5)	0.063 (5)	0.051 (5)	0.047 (4)	0.016 (4)	0.014 (4)
C26	0.065 (5)	0.050 (5)	0.070 (5)	0.039 (4)	0.014 (4)	0.025 (4)
C27	0.053 (4)	0.040 (4)	0.064 (5)	0.030 (4)	0.022 (4)	0.027 (4)
O1	0.076 (6)	0.042 (5)	0.057 (6)	0.020 (5)	0.013 (5)	0.025 (4)
O2	0.036 (2)	0.028 (2)	0.048 (3)	0.0158 (19)	0.010 (2)	0.015 (2)
O3	0.050 (6)	0.027 (5)	0.046 (5)	0.017 (4)	0.006 (4)	0.015 (4)
C1	0.040 (6)	0.024 (5)	0.046 (6)	0.014 (5)	0.011 (5)	0.022 (5)
C2	0.028 (5)	0.023 (5)	0.029 (6)	0.017 (4)	0.009 (4)	0.022 (5)
C3	0.030 (6)	0.033 (6)	0.029 (6)	0.014 (5)	0.014 (4)	0.011 (5)
N2	0.040 (5)	0.027 (5)	0.030 (5)	0.021 (4)	0.002 (4)	0.018 (4)
C4	0.024 (5)	0.038 (6)	0.035 (6)	0.017 (5)	0.012 (4)	0.014 (5)
N1	0.039 (6)	0.029 (6)	0.034 (6)	0.021 (5)	0.004 (4)	0.013 (5)
C5	0.041 (6)	0.043 (7)	0.037 (6)	0.019 (5)	0.016 (5)	0.018 (5)

Geometric parameters (Å, º) top

Nd1—O2	2.526 (4)	C10—H10	0.93
Nd1—O3	2.502 (9)	C11—C12	1.485 (8)
Nd1—O5	2.392 (4)	C12—C15	1.355 (8)
Nd1—O6	2.575 (4)	C12—C13	1.431 (8)
Nd1—O9	2.341 (4)	C15—H15	0.93
Nd1—O10	2.526 (4)	C16—C17	1.391 (10)
Nd1—O1W	2.475 (4)	C16—H16	0.93
Nd1—N1ⁱ	2.478 (6)	C17—C18	1.366 (11)
Nd1—N7	2.638 (5)	C17—H17	0.93
Nd1—N8	2.725 (5)	C18—C19	1.361 (11)
O4—C6	1.234 (7)	C18—H18	0.93
O5—C6	1.268 (7)	C19—C20	1.419 (9)
O6—C8	1.233 (7)	C19—C21	1.431 (11)
O7—C9	1.229 (8)	C20—C24	1.427 (9)
O8—C11	1.232 (7)	C21—C22	1.330 (12)
O9—C11	1.279 (7)	C21—H21	0.93
O10—C13	1.252 (7)	C22—C23	1.424 (11)
O11—C14	1.222 (7)	C22—H22	0.93
O1W—H1W1	0.85	C23—C25	1.381 (11)
O1W—H1W2	0.85	C23—C24	1.402 (9)
N3—C10	1.351 (8)	C25—C26	1.361 (12)
N3—C9	1.366 (9)	C25—H25	0.93
N3—H3N	0.86	C26—C27	1.391 (9)
N4—C9	1.367 (8)	C26—H26	0.93
N4—C8	1.378 (7)	C27—H27	0.93
N4—H4N	0.86	O1—C1	1.238 (8)
N5—C15	1.345 (8)	O2—C1	1.191 (8)
N5—C14	1.354 (7)	O3—C3	1.307 (8)
N5—H5N	0.86	C1—C2	1.473 (8)
N6—C13	1.368 (7)	C2—C3	1.39
N6—C14	1.371 (7)	C2—C5	1.39
N6—H6N	0.86	C3—N2	1.39
N7—C16	1.305 (9)	N2—C4	1.39
N7—C20	1.375 (8)	N2—H2N	0.86
N8—C27	1.343 (9)	C4—N1	1.39
N8—C24	1.358 (8)	N1—C5	1.39
C6—C7	1.487 (8)	N1—Nd1ⁱ	2.478 (6)
C7—C10	1.346 (8)	C5—H5	0.93
C7—C8	1.438 (8)

O2—Nd1—O3	67.5 (2)	O7—C9—N4	122.9 (7)
O2—Nd1—O5	71.6 (1)	N3—C9—N4	114.1 (6)
O2—Nd1—O6	123.5 (1)	C7—C10—N3	123.2 (6)
O2—Nd1—O9	127.7 (1)	C7—C10—H10	118.4
O2—Nd1—O10	71.8 (1)	N3—C10—H10	118.4
O2—Nd1—O1W	136.6 (2)	O8—C11—O9	124.9 (6)
O2—Nd1—N7	70.6 (2)	O8—C11—C12	118.8 (6)
O2—Nd1—N8	111.7 (2)	O9—C11—C12	116.3 (5)
O3—Nd1—O5	138.7 (2)	C15—C12—C13	117.4 (5)
O3—Nd1—O6	133.6 (3)	C15—C12—C11	119.2 (5)
O3—Nd1—O9	68.6 (3)	C13—C12—C11	123.3 (5)
O3—Nd1—O10	76.5 (3)	O10—C13—N6	116.8 (5)
O3—Nd1—O1W	138.2 (3)	O10—C13—C12	126.6 (5)
O3—Nd1—N7	87.9 (3)	N6—C13—C12	116.6 (5)
O3—Nd1—N8	65.6 (3)	O11—C14—N5	122.8 (6)
O5—Nd1—O6	67.9 (1)	O11—C14—N6	122.0 (6)
O5—Nd1—O9	139.7 (2)	N5—C14—N6	115.2 (5)
O5—Nd1—O10	85.9 (1)	N5—C15—C12	122.7 (5)
O5—Nd1—O1W	78.2 (2)	N5—C15—H15	118.7
O5—Nd1—N7	83.8 (2)	C12—C15—H15	118.7
O5—Nd1—N8	138.8 (2)	N7—C16—C17	123.6 (7)
O6—Nd1—O9	72.6 (1)	N7—C16—H16	118.2
O6—Nd1—O10	67.7 (1)	C17—C16—H16	118.2
O6—Nd1—O1W	69.0 (1)	C18—C17—C16	119.1 (8)
O6—Nd1—N7	138.2 (2)	C18—C17—H17	120.5
O6—Nd1—N8	124.8 (2)	C16—C17—H17	120.5
O9—Nd1—O10	71.5 (1)	C19—C18—C17	120.1 (7)
O9—Nd1—O1W	95.5 (2)	C19—C18—H18	120.0
O9—Nd1—N7	133.8 (2)	C17—C18—H18	120.0
O9—Nd1—N8	72.8 (2)	C18—C19—C20	118.1 (7)
O10—Nd1—O1W	136.7 (2)	C18—C19—C21	123.4 (7)
O10—Nd1—N7	142.5 (2)	C20—C19—C21	118.5 (8)
O10—Nd1—N8	135.1 (2)	N7—C20—C19	121.5 (7)
O1W—Nd1—N7	75.78 (16)	N7—C20—C24	119.0 (6)
O1W—Nd1—N8	72.93 (16)	C19—C20—C24	119.5 (6)
N7—Nd1—N8	61.14 (16)	C22—C21—C19	121.9 (7)
O9—Nd1—N1ⁱ	80.8 (3)	C22—C21—H21	119.1
O5—Nd1—N1ⁱ	124.7 (3)	C19—C21—H21	119.1
O1W—Nd1—N1ⁱ	147.5 (3)	C21—C22—C23	120.8 (7)
N1ⁱ—Nd1—O3	14.1 (3)	C21—C22—H22	119.6
N1ⁱ—Nd1—O10	73.0 (3)	C23—C22—H22	119.6
N1ⁱ—Nd1—O2	53.4 (2)	C25—C23—C24	118.0 (7)
N1ⁱ—Nd1—O6	137.7 (4)	C25—C23—C22	122.0 (7)
N1ⁱ—Nd1—N7	83.6 (4)	C24—C23—C22	119.9 (8)
N1ⁱ—Nd1—N8	75.1 (3)	N8—C24—C23	122.7 (7)
C6—O5—Nd1	140.6 (4)	N8—C24—C20	117.9 (5)
C8—O6—Nd1	123.2 (4)	C23—C24—C20	119.4 (6)
C11—O9—Nd1	137.2 (4)	C26—C25—C23	119.8 (7)
C13—O10—Nd1	130.2 (4)	C26—C25—H25	120.1
Nd1—O1W—H1W1	117.9	C23—C25—H25	120.1
Nd1—O1W—H1W2	107.8	C25—C26—C27	119.5 (8)
H1W1—O1W—H1W2	107.7	C25—C26—H26	120.2
C10—N3—C9	122.5 (6)	C27—C26—H26	120.2
C10—N3—H3N	118.7	N8—C27—C26	122.6 (7)
C9—N3—H3N	118.7	N8—C27—H27	118.7
C9—N4—C8	126.9 (6)	C26—C27—H27	118.7
C9—N4—H4N	116.5	C1—O2—Nd1	143.9 (5)
C8—N4—H4N	116.5	C3—O3—Nd1	135.9 (6)
C15—N5—C14	122.6 (5)	O2—C1—O1	120.4 (8)
C15—N5—H5N	118.7	O2—C1—C2	119.1 (7)
C14—N5—H5N	118.7	O1—C1—C2	120.5 (8)
C13—N6—C14	125.4 (5)	C3—C2—C5	120.0
C13—N6—H6N	117.3	C3—C2—C1	124.7 (6)
C14—N6—H6N	117.3	C5—C2—C1	115.3 (6)
C16—N7—C20	117.7 (6)	O3—C3—N2	113.1 (6)
C16—N7—Nd1	120.3 (4)	O3—C3—C2	126.9 (6)
C20—N7—Nd1	121.9 (4)	N2—C3—C2	120.0
C27—N8—C24	117.3 (6)	C4—N2—C3	120.0
C27—N8—Nd1	122.7 (4)	C4—N2—H2N	120.0
C24—N8—Nd1	119.9 (4)	C3—N2—H2N	120.0
O4—C6—O5	123.3 (6)	N2—C4—N1	120.0
O4—C6—C7	118.8 (5)	N2—C4—Nd1ⁱ	175.4 (3)
O5—C6—C7	117.9 (5)	N1—C4—Nd1ⁱ	55.6 (3)
C10—C7—C8	117.7 (6)	C5—N1—C4	120.0
C10—C7—C6	119.6 (5)	C5—N1—Nd1ⁱ	143.1 (4)
C8—C7—C6	122.7 (5)	C4—N1—Nd1ⁱ	96.8 (4)
O6—C8—N4	118.1 (5)	N1—C5—C2	120.0
O6—C8—C7	126.6 (5)	N1—C5—H5	120.0
N4—C8—C7	115.3 (5)	C2—C5—H5	120.0
O7—C9—N3	123.0 (7)

O9—Nd1—O5—C6	21.5 (8)	C9—N3—C10—C7	−0.6 (11)
O1W—Nd1—O5—C6	106.0 (7)	Nd1—O9—C11—O8	−131.1 (6)
N1ⁱ—Nd1—O5—C6	−99.5 (8)	Nd1—O9—C11—C12	50.7 (8)
O3—Nd1—O5—C6	−97.6 (8)	O8—C11—C12—C15	−30.9 (9)
O10—Nd1—O5—C6	−33.4 (6)	O9—C11—C12—C15	147.5 (6)
O2—Nd1—O5—C6	−105.6 (7)	O8—C11—C12—C13	153.3 (6)
O6—Nd1—O5—C6	34.1 (6)	O9—C11—C12—C13	−28.4 (9)
N7—Nd1—O5—C6	−177.3 (7)	Nd1—O10—C13—N6	−156.8 (4)
N8—Nd1—O5—C6	152.1 (6)	Nd1—O10—C13—C12	24.7 (9)
C4ⁱ—Nd1—O5—C6	−104.4 (7)	C14—N6—C13—O10	179.7 (6)
O9—Nd1—O6—C8	125.4 (5)	C14—N6—C13—C12	−1.7 (9)
O5—Nd1—O6—C8	−46.1 (4)	C15—C12—C13—O10	177.3 (6)
O1W—Nd1—O6—C8	−131.5 (5)	C11—C12—C13—O10	−6.8 (10)
N1ⁱ—Nd1—O6—C8	71.6 (6)	C15—C12—C13—N6	−1.2 (8)
O3—Nd1—O6—C8	90.9 (5)	C11—C12—C13—N6	174.7 (5)
O10—Nd1—O6—C8	48.7 (4)	C15—N5—C14—O11	178.8 (7)
O2—Nd1—O6—C8	1.2 (5)	C15—N5—C14—N6	−1.8 (10)
N7—Nd1—O6—C8	−97.0 (5)	C13—N6—C14—O11	−177.5 (6)
N8—Nd1—O6—C8	179.0 (4)	C13—N6—C14—N5	3.1 (10)
C4ⁱ—Nd1—O6—C8	30.3 (6)	C14—N5—C15—C12	−1.0 (10)
O5—Nd1—O9—C11	−89.4 (6)	C13—C12—C15—N5	2.5 (9)
O1W—Nd1—O9—C11	−167.6 (6)	C11—C12—C15—N5	−173.6 (6)
N1ⁱ—Nd1—O9—C11	45.0 (6)	C20—N7—C16—C17	−0.5 (10)
O3—Nd1—O9—C11	52.3 (6)	Nd1—N7—C16—C17	−179.3 (6)
O10—Nd1—O9—C11	−30.0 (6)	N7—C16—C17—C18	0.2 (12)
O2—Nd1—O9—C11	17.6 (6)	C16—C17—C18—C19	0.2 (12)
O6—Nd1—O9—C11	−101.6 (6)	C17—C18—C19—C20	−0.2 (11)
N7—Nd1—O9—C11	116.9 (6)	C17—C18—C19—C21	178.3 (8)
N8—Nd1—O9—C11	122.2 (6)	C16—N7—C20—C19	0.5 (9)
C4ⁱ—Nd1—O9—C11	33.9 (6)	Nd1—N7—C20—C19	179.3 (5)
O9—Nd1—O10—C13	−10.0 (5)	C16—N7—C20—C24	179.6 (6)
O5—Nd1—O10—C13	136.0 (5)	Nd1—N7—C20—C24	−1.6 (8)
O1W—Nd1—O10—C13	68.0 (6)	C18—C19—C20—N7	−0.1 (10)
N1ⁱ—Nd1—O10—C13	−95.8 (6)	C21—C19—C20—N7	−178.7 (6)
O3—Nd1—O10—C13	−81.7 (5)	C18—C19—C20—C24	−179.3 (7)
O2—Nd1—O10—C13	−152.0 (5)	C21—C19—C20—C24	2.2 (10)
O6—Nd1—O10—C13	68.3 (5)	C18—C19—C21—C22	−179.8 (8)
N7—Nd1—O10—C13	−149.7 (5)	C20—C19—C21—C22	−1.3 (12)
N8—Nd1—O10—C13	−49.2 (6)	C19—C21—C22—C23	−1.2 (13)
C4ⁱ—Nd1—O10—C13	−124.7 (5)	C21—C22—C23—C25	−176.1 (8)
O9—Nd1—N7—C16	−173.0 (5)	C21—C22—C23—C24	2.8 (12)
O5—Nd1—N7—C16	23.8 (5)	C27—N8—C24—C23	1.0 (10)
O1W—Nd1—N7—C16	103.2 (5)	Nd1—N8—C24—C23	−177.9 (5)
N1ⁱ—Nd1—N7—C16	−102.2 (6)	C27—N8—C24—C20	−176.9 (6)
O3—Nd1—N7—C16	−115.7 (5)	Nd1—N8—C24—C20	4.2 (8)
O10—Nd1—N7—C16	−51.2 (6)	C25—C23—C24—N8	−0.8 (10)
O2—Nd1—N7—C16	−48.8 (5)	C22—C23—C24—N8	−179.7 (7)
O6—Nd1—N7—C16	70.1 (6)	C25—C23—C24—C20	177.1 (7)
N8—Nd1—N7—C16	−178.7 (6)	C22—C23—C24—C20	−1.8 (10)
C4ⁱ—Nd1—N7—C16	−75.8 (5)	N7—C20—C24—N8	−1.8 (9)
O9—Nd1—N7—C20	8.2 (6)	C19—C20—C24—N8	177.3 (6)
O5—Nd1—N7—C20	−155.0 (5)	N7—C20—C24—C23	−179.8 (6)
O1W—Nd1—N7—C20	−75.6 (5)	C19—C20—C24—C23	−0.6 (9)
N1ⁱ—Nd1—N7—C20	79.0 (5)	C24—C23—C25—C26	−0.7 (11)
O3—Nd1—N7—C20	65.6 (5)	C22—C23—C25—C26	178.2 (8)
O10—Nd1—N7—C20	130.0 (4)	C23—C25—C26—C27	1.9 (12)
O2—Nd1—N7—C20	132.4 (5)	C24—N8—C27—C26	0.3 (11)
O6—Nd1—N7—C20	−108.7 (5)	Nd1—N8—C27—C26	179.2 (6)
N8—Nd1—N7—C20	2.5 (4)	C25—C26—C27—N8	−1.8 (12)
C4ⁱ—Nd1—N7—C20	105.4 (5)	O9—Nd1—O2—C1	50.4 (6)
O9—Nd1—N8—C27	2.1 (5)	O5—Nd1—O2—C1	−170.3 (6)
O5—Nd1—N8—C27	−147.0 (5)	O1W—Nd1—O2—C1	−122.0 (6)
O1W—Nd1—N8—C27	−99.4 (6)	N1ⁱ—Nd1—O2—C1	16.0 (8)
N1ⁱ—Nd1—N8—C27	86.9 (6)	O3—Nd1—O2—C1	15.5 (6)
O3—Nd1—N8—C27	75.9 (6)	O10—Nd1—O2—C1	98.0 (6)
O10—Nd1—N8—C27	40.9 (6)	O6—Nd1—O2—C1	143.8 (6)
O2—Nd1—N8—C27	126.6 (5)	N7—Nd1—O2—C1	−80.5 (6)
O6—Nd1—N8—C27	−51.4 (6)	N8—Nd1—O2—C1	−34.2 (6)
N7—Nd1—N8—C27	177.7 (6)	C4ⁱ—Nd1—O2—C1	12.6 (9)
C4ⁱ—Nd1—N8—C27	108.0 (6)	O9—Nd1—O3—C3	−151.4 (14)
O9—Nd1—N8—C24	−179.1 (5)	O5—Nd1—O3—C3	−8.8 (16)
O5—Nd1—N8—C24	31.9 (6)	O1W—Nd1—O3—C3	135.1 (11)
O1W—Nd1—N8—C24	79.4 (5)	N1ⁱ—Nd1—O3—C3	−2 (2)
N1ⁱ—Nd1—N8—C24	−94.3 (6)	O10—Nd1—O3—C3	−76.2 (13)
O3—Nd1—N8—C24	−105.3 (5)	O2—Nd1—O3—C3	−0.5 (12)
O10—Nd1—N8—C24	−140.3 (4)	O6—Nd1—O3—C3	−116.0 (12)
O2—Nd1—N8—C24	−54.6 (5)	N7—Nd1—O3—C3	69.4 (13)
O6—Nd1—N8—C24	127.4 (4)	N8—Nd1—O3—C3	128.4 (14)
N7—Nd1—N8—C24	−3.4 (4)	C4ⁱ—Nd1—O3—C3	1.4 (13)
C4ⁱ—Nd1—N8—C24	−73.2 (5)	Nd1—O2—C1—O1	158.2 (7)
Nd1—O5—C6—O4	168.0 (5)	Nd1—O2—C1—C2	−21.9 (7)
Nd1—O5—C6—C7	−12.1 (9)	O2—C1—C2—C3	10.7 (6)
O4—C6—C7—C10	−19.2 (9)	O1—C1—C2—C3	−169.4 (6)
O5—C6—C7—C10	160.9 (6)	O2—C1—C2—C5	−168.7 (5)
O4—C6—C7—C8	160.7 (6)	O1—C1—C2—C5	11.2 (5)
O5—C6—C7—C8	−19.2 (8)	Nd1—O3—C3—N2	175.8 (8)
Nd1—O6—C8—N4	−137.4 (5)	Nd1—O3—C3—C2	−3.7 (18)
Nd1—O6—C8—C7	44.3 (8)	C5—C2—C3—O3	179.5 (12)
C9—N4—C8—O6	177.5 (7)	C1—C2—C3—O3	0.1 (11)
C9—N4—C8—C7	−4.0 (10)	C5—C2—C3—N2	0.0
C10—C7—C8—O6	178.5 (6)	C1—C2—C3—N2	−179.4 (6)
C6—C7—C8—O6	−1.3 (9)	O3—C3—N2—C4	−179.6 (11)
C10—C7—C8—N4	0.2 (8)	C2—C3—N2—C4	0.0
C6—C7—C8—N4	−179.7 (5)	C3—N2—C4—N1	0.0
C10—N3—C9—O7	175.9 (8)	N2—C4—N1—C5	0.0
C10—N3—C9—N4	−2.7 (11)	N2—C4—N1—Nd1ⁱ	−178.2 (5)
C8—N4—C9—O7	−173.4 (8)	C4—N1—C5—C2	0.0
C8—N4—C9—N3	5.2 (11)	Nd1ⁱ—N1—C5—C2	177.1 (8)
C8—C7—C10—N3	1.9 (10)	C3—C2—C5—N1	0.0
C6—C7—C10—N3	−178.2 (6)	C1—C2—C5—N1	179.4 (6)

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
N3—H3N···O1ⁱⁱ	0.86	2.19	2.877 (13)	136
N3—H3N···O2ⁱⁱ	0.86	2.10	2.883 (7)	152
N4—H4N···O8ⁱⁱⁱ	0.86	1.91	2.768 (7)	175
N5—H5N···O11^iv	0.86	1.95	2.786 (7)	164
N6—H6N···O4ⁱⁱ	0.86	1.86	2.709 (6)	167
O1W—H1W1···O4^v	0.85	2.04	2.822 (7)	153
O1W—H1W2···O11^vi	0.85	2.14	2.921 (6)	153

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

Experimental details

Crystal data
Chemical formula	[Nd₂(C₅H₂N₂O₄)(C₅H₃N₂O₄)₄(C₁₂H₈N₂)₂(H₂O)₂]·6H₂O
M_r	1567.48
Crystal system, space group	Triclinic, P1
Temperature (K)	295
a, b, c (Å)	10.1980 (7), 12.8896 (9), 13.3383 (9)
α, β, γ (°)	118.711 (1), 90.010 (1), 108.612 (1)
V (Å³)	1432.25 (17)
Z	1
Radiation type	Mo Kα
µ (mm⁻¹)	1.90
Crystal size (mm)	0.10 × 0.04 × 0.02

Data collection
Diffractometer	Bruker APEXII diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.724, 0.963
No. of measured, independent and observed [I > 2σ(I)] reflections	12405, 6377, 5349
R_int	0.039
(sin θ/λ)_max (Å⁻¹)	0.650

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.054, 0.136, 1.04
No. of reflections	6377
No. of parameters	454
No. of restraints	84
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.23, −0.90

Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2006), atomic coordinates taken from the Pr analog (Sun & Jin, 2004), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2008).

Selected geometric parameters (Å, º) top

Nd1—O2	2.526 (4)	Nd1—O10	2.526 (4)
Nd1—O3	2.502 (9)	Nd1—O1W	2.475 (4)
Nd1—O5	2.392 (4)	Nd1—N7	2.638 (5)
Nd1—O6	2.575 (4)	Nd1—N8	2.725 (5)
Nd1—O9	2.341 (4)

O2—Nd1—O3	67.5 (2)	O5—Nd1—O1W	78.2 (2)
O2—Nd1—O5	71.6 (1)	O5—Nd1—N7	83.8 (2)
O2—Nd1—O6	123.5 (1)	O5—Nd1—N8	138.8 (2)
O2—Nd1—O9	127.7 (1)	O6—Nd1—O9	72.6 (1)
O2—Nd1—O10	71.8 (1)	O6—Nd1—O10	67.7 (1)
O2—Nd1—O1W	136.6 (2)	O6—Nd1—O1W	69.0 (1)
O2—Nd1—N7	70.6 (2)	O6—Nd1—N7	138.2 (2)
O2—Nd1—N8	111.7 (2)	O6—Nd1—N8	124.8 (2)
O3—Nd1—O5	138.7 (2)	O9—Nd1—O10	71.5 (1)
O3—Nd1—O6	133.6 (3)	O9—Nd1—O1W	95.5 (2)
O3—Nd1—O9	68.6 (3)	O9—Nd1—N7	133.8 (2)
O3—Nd1—O10	76.5 (3)	O9—Nd1—N8	72.8 (2)
O3—Nd1—O1W	138.2 (3)	O10—Nd1—O1W	136.7 (2)
O3—Nd1—N7	87.9 (3)	O10—Nd1—N7	142.5 (2)
O3—Nd1—N8	65.6 (3)	O10—Nd1—N8	135.1 (2)
O5—Nd1—O6	67.9 (1)	O1W—Nd1—N7	75.78 (16)
O5—Nd1—O9	139.7 (2)	O1W—Nd1—N8	72.93 (16)
O5—Nd1—O10	85.9 (1)	N7—Nd1—N8	61.14 (16)

Acknowledgements

The authors thank the Scientifc Research Foundation of Guangxi Normal University, the Science Foundation of Guangxi (grant No. 0542021) and the University of Malaya for supporting this study.

References

Barbour, L. J. (2001). J. Supramol. Chem., 1, 189–191. CrossRef CAS Google Scholar
Bruker (2006). APEX2 and SAINT. Bruker AXS Inc., Madison, Winconsin, USA. Google Scholar
Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Sun, C.-Y. & Jin, L. P. (2004). Polyhedron, 23, 2085–2093. Web of Science CSD CrossRef CAS Google Scholar
Westrip, S. P. (2008). publCIF. In preparation. Google Scholar
Xing, H.-H., Chen, Z.-L. & Ng, S. W. (2008). Acta Cryst. E64, m418. Web of Science CSD CrossRef IUCr Journals Google Scholar

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