metal-organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 64| Part 5| May 2008| Pages m685-m686
RETRACTED ARTICLE

This article has been retracted. To view the retraction notice, click here.

Retracted: Di­aqua­bis­(pyridine-2-carboxyl­ato-κ2N,O)cobalt(II)

aCollege of Chemistry & Chemical Engineering, Provincial Key Laboratory of Coordination Chemistry, Jinggangshan University, Jian 343009, People's Republic of China
*Correspondence e-mail: gshuang08@126.com

(Received 7 April 2008; accepted 16 April 2008; online 18 April 2008)

In the mol­ecule of the title compound, [Co(C6H4NO2)2(H2O)2], the coordination environment around the CoII atom is distorted octahedral; two N and two O atoms of the pyridine-2-carboxylate ligands lie in the equatorial plane and the two water O atoms in the axial positions. In the crystal structure, inter­molecular O—H⋯O hydrogen bonds link the mol­ecules, forming a supra­moleular network structure.

Related literature

For general background, see: Desiraju (1997[Desiraju, G. R. (1997). J. Chem. Soc. Chem. Commun. pp. 1475-1476.]); Braga et al. (1998[Braga, D., Grepioni, F. & Desiraju, G. R. (1998). Chem. Rev. 98, 1375-1386.]); McCann et al. (1996[McCann, M., Casey, M. T., Devereux, M., Curran, M., Cardin, C. & Todd, A. (1996). Polyhedron, 15, 2117-2120.]); Wai et al. (1990[Wai, H. Y., Ru, J. W. & Mark, T. C. W. (1990). J. Crystallogr. Spectrosc. Res. 20, 307-312.]); Yaghi et al. (1996[Yaghi, O. M., Li, H. & Groy, T. L. (1996). J. Am. Chem. Soc. 118, 9096-9101.]); Min & Lee (2002[Min, D. & Lee, S. M. (2002). Inorg. Chem. Commun. 5, 978-983.]); Maira et al. (2001[Maira, S. M., Galetic, I., Brazil, D. P., Decech, S., Ingley, E., Thelen, M. & Hemmings, B. A. (2001). Science, 294, 374-380.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data
  • [Co(C6H4NO2)2(H2O)2]

  • Mr = 339.17

  • Monoclinic, P 21 /n

  • a = 11.7401 (3) Å

  • b = 8.9994 (6) Å

  • c = 14.9211 (3) Å

  • β = 105.985 (2)°

  • V = 1515.52 (11) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 1.16 mm−1

  • T = 273 (2) K

  • 0.24 × 0.18 × 0.08 mm

Data collection
  • Bruker APEXII area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.770, Tmax = 0.918

  • 9384 measured reflections

  • 2926 independent reflections

  • 2065 reflections with I > 2σ(I)

  • Rint = 0.042

Refinement
  • R[F2 > 2σ(F2)] = 0.060

  • wR(F2) = 0.227

  • S = 1.07

  • 2926 reflections

  • 200 parameters

  • 6 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.83 e Å−3

  • Δρmin = −0.62 e Å−3

Table 1
Selected geometric parameters (Å, °)

Co1—O1 2.150 (3)
Co1—O2 2.162 (3)
Co1—O3 2.151 (3)
Co1—O5 2.153 (3)
Co1—N1 2.284 (4)
Co1—N2 2.274 (3)
O1—Co1—O2 84.68 (13)
O1—Co1—O3 167.36 (12)
O1—Co1—O5 98.78 (12)
O2—Co1—O3 92.63 (13)
O2—Co1—O5 95.35 (13)
O3—Co1—O5 93.75 (12)
O1—Co1—N1 86.44 (14)
O2—Co1—N1 163.96 (15)
O3—Co1—N1 98.83 (14)
O5—Co1—N1 72.84 (12)
O1—Co1—N2 93.86 (12)
O2—Co1—N2 98.99 (14)
O3—Co1—N2 74.33 (12)
O5—Co1—N2 161.68 (13)
N1—Co1—N2 94.91 (13)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1B⋯O4i 0.784 (18) 1.98 (3) 2.733 (4) 161 (4)
O1—H1A⋯O5ii 0.82 1.88 2.679 (4) 164
O2—H2B⋯O4iii 0.771 (16) 1.959 (16) 2.712 (4) 166 (3)
O2—H2A⋯O6ii 0.82 1.96 2.699 (5) 149
Symmetry codes: (i) [x+{\script{1\over 2}}, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]; (ii) [-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]; (iii) -x+1, -y+2, -z+1.

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Siemens, 1996[Siemens (1996). SAINT. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

In the synthesis of crystal structures by design, the assembly of molecular units in predefined arrangements is a key goal (Desiraju, 1997; Braga et al., 1998). Due to carboxyl groups are one of the most important classes of biological ligands, the coordination of metal-carboxyl groups complexes are of critical importance in biological systems, organic materials and coordination chemistry. Recently, carboxyl groups with variable coordination modes have been used to construct metal-organic supramolecular structures (McCann et al., 1996; Wai et al., 1990; Yaghi et al., 1996; Min & Lee 2002; Maira et al., 2001). We report herein the crystal structure of the title compound, (I).

In the molecule of (I) (Fig. 1), the ligand bond lengths (Allen et al., 1987) and angles are within normal ranges. The two N and the two O atoms of the two pyridine-2-carboxylato ligands in the equatorial plane around the CoII atom form a distorted square-planar arrangement, while the distorted octahedral coordination is completed by the two O atoms of water molecules in the axial positions (Table 1 and Fig. 1). The Co-O bonds [average 2.154 (3) Å] are somewhat shorter than the Co-N distances [average 2.279 (3) Å].

In the crystal structure, intermolecular O-H···O hydrogen bonds (Table 2) link the molecules to form a supramoleular network structure (Fig. 2), in which they may be effective in the stabilization of the structure.

Related literature top

For general backgroud, see: Desiraju (1997); Braga et al. (1998); McCann et al. (1996); Wai et al. (1990); Yaghi et al. (1996); Min & Lee (2002); Maira et al. (2001). For bond-length data, see: Allen et al. (1987).

Experimental top

The title compound was synthesized using hydrothermal method in a 23 ml Teflon-lined Parr bomb. Cobalt(II) chloride hexahydrate (47.6 mg, 0.2 mmol), pyridine-2-carboxylic acid (49.2 mg, 0.4 mmol) and distilled water (6 g) were placed into the bomb and sealed. The bomb was then heated under autogenous pressure up to 413 K over the course of 7 d and allowed to cool at room temperature for 24 h. Upon opening the bomb, a clear colorless solution was decanted from small pink crystals. These crystals were washed with distilled water followed by ethanol, and allowed to air-dry at room temperature.

Refinement top

H1B and H2B (for H2O) were located in difference syntheses and refined isotropically [O-H = 0.784 (18) and 0.771 (16) Å, Uiso(H) = 0.065 (16) and 0.035 (12) Å2]. The remaining H1A and H2A (for H2O) and aromatic H atoms were positioned geometrically, with O-H = 0.82 Å (for H2O) and C-H = 0.93 Å for aromatic H, and constrained to ride on their parent atoms, with Uiso(H) = xUeq(C,O), where x = 1.2 for aromatic H atoms and x = 1.5 for all other H atoms.

Computing details top

Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT (Siemens, 1996); 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
[Figure 1] Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. Hydrogen bond is shown as dashed line.
[Figure 2] Fig. 2. A packing diagram of (I). Hydrogen bonds are shown as dashed lines.
Diaquabis(pyridine-2-carboxylato-κ2N,O)cobalt(II) top
Crystal data top
[Co(C6H4NO2)2(H2O)2]F(000) = 692
Mr = 339.17Dx = 1.486 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 2863 reflections
a = 11.7401 (3) Åθ = 2.6–23.8°
b = 8.9994 (6) ŵ = 1.16 mm1
c = 14.9211 (3) ÅT = 273 K
β = 105.985 (2)°Plate, pink
V = 1515.52 (11) Å30.24 × 0.18 × 0.08 mm
Z = 4
Data collection top
Bruker APEXII area-detector
diffractometer
2926 independent reflections
Radiation source: fine-focus sealed tube2065 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.042
ϕ and ω scansθmax = 26.0°, θmin = 2.0°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 1414
Tmin = 0.770, Tmax = 0.918k = 1111
9384 measured reflectionsl = 1817
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.060Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.227H atoms treated by a mixture of independent and constrained refinement
S = 1.07 w = 1/[σ2(Fo2) + (0.152P)2 + 0.1958P]
where P = (Fo2 + 2Fc2)/3
2926 reflections(Δ/σ)max < 0.001
200 parametersΔρmax = 0.83 e Å3
6 restraintsΔρmin = 0.62 e Å3
Crystal data top
[Co(C6H4NO2)2(H2O)2]V = 1515.52 (11) Å3
Mr = 339.17Z = 4
Monoclinic, P21/nMo Kα radiation
a = 11.7401 (3) ŵ = 1.16 mm1
b = 8.9994 (6) ÅT = 273 K
c = 14.9211 (3) Å0.24 × 0.18 × 0.08 mm
β = 105.985 (2)°
Data collection top
Bruker APEXII area-detector
diffractometer
2926 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
2065 reflections with I > 2σ(I)
Tmin = 0.770, Tmax = 0.918Rint = 0.042
9384 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0606 restraints
wR(F2) = 0.227H atoms treated by a mixture of independent and constrained refinement
S = 1.07Δρmax = 0.83 e Å3
2926 reflectionsΔρmin = 0.62 e Å3
200 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 > 2sigma(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
xyzUiso*/Ueq
Co10.74558 (5)0.85905 (7)0.62775 (4)0.0500 (3)
O10.8193 (3)0.7460 (4)0.7578 (2)0.0528 (8)
H1A0.76620.70360.77370.079*
H1B0.8854 (17)0.719 (5)0.773 (3)0.065 (16)*
O20.5921 (3)0.8896 (4)0.6792 (3)0.0562 (9)
H2A0.58260.81560.70830.084*
H2B0.546 (3)0.953 (3)0.673 (3)0.035 (12)*
O30.6510 (3)0.9270 (3)0.48901 (19)0.0497 (8)
O40.5390 (3)0.8577 (3)0.3503 (2)0.0560 (9)
O50.8183 (3)1.0767 (4)0.6673 (2)0.0512 (8)
O60.9716 (3)1.2287 (4)0.6898 (3)0.0724 (11)
N10.9333 (3)0.8598 (4)0.6113 (3)0.0504 (9)
N20.6905 (3)0.6452 (4)0.5461 (2)0.0406 (8)
C10.6032 (3)0.8310 (5)0.4295 (3)0.0423 (9)
C20.6267 (3)0.6693 (5)0.4583 (3)0.0392 (9)
C30.5838 (4)0.5535 (5)0.3968 (3)0.0533 (11)
H30.54240.57220.33510.064*
C40.6040 (4)0.4115 (6)0.4293 (3)0.0552 (11)
H40.57270.33190.39060.066*
C50.6700 (4)0.3862 (5)0.5184 (4)0.0552 (12)
H50.68640.28970.54040.066*
C60.7120 (4)0.5054 (5)0.5755 (3)0.0495 (10)
H60.75690.48800.63640.059*
C70.9224 (4)1.1095 (5)0.6665 (3)0.0513 (11)
C80.9904 (4)0.9869 (5)0.6340 (3)0.0489 (11)
C91.1060 (4)1.0058 (7)0.6312 (4)0.0704 (15)
H91.14431.09610.64850.085*
C101.1635 (6)0.8917 (7)0.6029 (6)0.091 (2)
H101.24030.90390.59830.109*
C111.1064 (6)0.7581 (8)0.5811 (6)0.102 (2)
H111.14450.67680.56390.123*
C120.9906 (5)0.7476 (6)0.5856 (5)0.0772 (17)
H120.95100.65780.56980.093*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Co10.0509 (5)0.0450 (5)0.0472 (5)0.0007 (3)0.0018 (3)0.0005 (2)
O10.0397 (16)0.060 (2)0.0502 (18)0.0013 (15)0.0015 (13)0.0150 (14)
O20.056 (2)0.0450 (19)0.070 (2)0.0125 (16)0.0209 (17)0.0143 (16)
O30.0515 (17)0.0412 (18)0.0466 (17)0.0020 (13)0.0031 (13)0.0045 (13)
O40.0550 (19)0.052 (2)0.0467 (18)0.0079 (14)0.0106 (14)0.0083 (13)
O50.0467 (17)0.0448 (18)0.0613 (19)0.0019 (14)0.0135 (14)0.0096 (15)
O60.078 (2)0.059 (2)0.089 (3)0.0299 (19)0.037 (2)0.031 (2)
N10.049 (2)0.046 (2)0.059 (2)0.0010 (17)0.0189 (18)0.0046 (17)
N20.0418 (18)0.037 (2)0.0366 (18)0.0012 (14)0.0011 (14)0.0024 (13)
C10.0331 (19)0.049 (2)0.040 (2)0.0023 (17)0.0035 (16)0.0025 (18)
C20.0334 (19)0.041 (2)0.039 (2)0.0012 (16)0.0032 (15)0.0034 (17)
C30.051 (2)0.053 (3)0.046 (2)0.005 (2)0.0033 (18)0.008 (2)
C40.056 (3)0.044 (3)0.061 (3)0.002 (2)0.008 (2)0.012 (2)
C50.064 (3)0.041 (3)0.064 (3)0.001 (2)0.023 (2)0.001 (2)
C60.057 (2)0.044 (3)0.044 (2)0.001 (2)0.0068 (19)0.0031 (19)
C70.059 (3)0.055 (3)0.039 (2)0.011 (2)0.0124 (19)0.0056 (19)
C80.050 (2)0.055 (3)0.042 (2)0.006 (2)0.0146 (18)0.0039 (19)
C90.058 (3)0.073 (4)0.086 (4)0.008 (3)0.027 (3)0.001 (3)
C100.069 (4)0.085 (5)0.134 (6)0.001 (4)0.054 (4)0.006 (4)
C110.085 (4)0.079 (5)0.165 (8)0.016 (4)0.074 (5)0.007 (5)
C120.076 (4)0.052 (3)0.114 (5)0.001 (3)0.043 (3)0.012 (3)
Geometric parameters (Å, º) top
Co1—O12.150 (3)C1—C21.521 (6)
Co1—O22.162 (3)C2—C31.389 (6)
Co1—O32.151 (3)C3—C41.365 (7)
Co1—O52.153 (3)C3—H30.9300
Co1—N12.284 (4)C4—C51.361 (7)
Co1—N22.274 (3)C4—H40.9300
O1—H1A0.8200C5—C61.374 (6)
O1—H1B0.784 (18)C5—H50.9300
O2—H2A0.8200C6—H60.9300
O2—H2B0.771 (16)C7—C81.517 (6)
O3—C11.255 (5)C8—C91.380 (7)
O4—C11.238 (5)C9—C101.359 (8)
O5—C71.261 (5)C9—H90.9300
O6—C71.222 (5)C10—C111.371 (9)
N1—C81.321 (6)C10—H100.9300
N1—C121.327 (6)C11—C121.383 (8)
N2—C61.334 (5)C11—H110.9300
N2—C21.335 (5)C12—H120.9300
O1—Co1—O284.68 (13)N2—C2—C1116.2 (3)
O1—Co1—O3167.36 (12)C3—C2—C1121.8 (4)
O1—Co1—O598.78 (12)C4—C3—C2118.2 (4)
O2—Co1—O392.63 (13)C4—C3—H3120.9
O2—Co1—O595.35 (13)C2—C3—H3120.9
O3—Co1—O593.75 (12)C5—C4—C3120.0 (4)
O1—Co1—N186.44 (14)C5—C4—H4120.0
O2—Co1—N1163.96 (15)C3—C4—H4120.0
O3—Co1—N198.83 (14)C4—C5—C6119.1 (5)
O5—Co1—N172.84 (12)C4—C5—H5120.5
O1—Co1—N293.86 (12)C6—C5—H5120.5
O2—Co1—N298.99 (14)N2—C6—C5122.0 (4)
O3—Co1—N274.33 (12)N2—C6—H6119.0
O5—Co1—N2161.68 (13)C5—C6—H6119.0
N1—Co1—N294.91 (13)O6—C7—O5125.9 (5)
Co1—O1—H1A109.5O6—C7—C8118.7 (4)
Co1—O1—H1B122 (3)O5—C7—C8115.4 (4)
H1A—O1—H1B123.0N1—C8—C9122.2 (4)
Co1—O2—H2A109.5N1—C8—C7116.0 (4)
Co1—O2—H2B132 (2)C9—C8—C7121.9 (5)
H2A—O2—H2B118.0C10—C9—C8119.5 (5)
C1—O3—Co1119.8 (3)C10—C9—H9120.2
C7—O5—Co1121.5 (3)C8—C9—H9120.2
C8—N1—C12118.1 (4)C9—C10—C11119.0 (5)
C8—N1—Co1114.3 (3)C9—C10—H10120.5
C12—N1—Co1127.5 (3)C11—C10—H10120.5
C6—N2—C2118.6 (4)C10—C11—C12118.1 (6)
C6—N2—Co1128.5 (3)C10—C11—H11120.9
C2—N2—Co1112.8 (3)C12—C11—H11120.9
O4—C1—O3125.3 (4)N1—C12—C11123.0 (6)
O4—C1—C2118.2 (4)N1—C12—H12118.5
O3—C1—C2116.6 (4)C11—C12—H12118.5
N2—C2—C3122.0 (4)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1B···O4i0.78 (2)1.98 (3)2.733 (4)161 (4)
O1—H1A···O5ii0.821.882.679 (4)164
O2—H2B···O4iii0.77 (2)1.96 (2)2.712 (4)166 (3)
O2—H2A···O6ii0.821.962.699 (5)149
Symmetry codes: (i) x+1/2, y+3/2, z+1/2; (ii) x+3/2, y1/2, z+3/2; (iii) x+1, y+2, z+1.

Experimental details

Crystal data
Chemical formula[Co(C6H4NO2)2(H2O)2]
Mr339.17
Crystal system, space groupMonoclinic, P21/n
Temperature (K)273
a, b, c (Å)11.7401 (3), 8.9994 (6), 14.9211 (3)
β (°) 105.985 (2)
V3)1515.52 (11)
Z4
Radiation typeMo Kα
µ (mm1)1.16
Crystal size (mm)0.24 × 0.18 × 0.08
Data collection
DiffractometerBruker APEXII area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.770, 0.918
No. of measured, independent and
observed [I > 2σ(I)] reflections
9384, 2926, 2065
Rint0.042
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.060, 0.227, 1.07
No. of reflections2926
No. of parameters200
No. of restraints6
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.83, 0.62

Computer programs: SMART (Siemens, 1996), SAINT (Siemens, 1996), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Selected geometric parameters (Å, º) top
Co1—O12.150 (3)Co1—O52.153 (3)
Co1—O22.162 (3)Co1—N12.284 (4)
Co1—O32.151 (3)Co1—N22.274 (3)
O1—Co1—O284.68 (13)O3—Co1—N198.83 (14)
O1—Co1—O3167.36 (12)O5—Co1—N172.84 (12)
O1—Co1—O598.78 (12)O1—Co1—N293.86 (12)
O2—Co1—O392.63 (13)O2—Co1—N298.99 (14)
O2—Co1—O595.35 (13)O3—Co1—N274.33 (12)
O3—Co1—O593.75 (12)O5—Co1—N2161.68 (13)
O1—Co1—N186.44 (14)N1—Co1—N294.91 (13)
O2—Co1—N1163.96 (15)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1B···O4i0.784 (18)1.98 (3)2.733 (4)161 (4)
O1—H1A···O5ii0.821.882.679 (4)164
O2—H2B···O4iii0.771 (16)1.959 (16)2.712 (4)166 (3)
O2—H2A···O6ii0.821.962.699 (5)149
Symmetry codes: (i) x+1/2, y+3/2, z+1/2; (ii) x+3/2, y1/2, z+3/2; (iii) x+1, y+2, z+1.
 

Acknowledgements

We thank the Youth Program of Jinggangshan University for financial support of this work.

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Volume 64| Part 5| May 2008| Pages m685-m686
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