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

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ISSN: 2056-9890
Volume 64| Part 12| December 2008| Pages m1550-m1551

Di­aqua­bis­(2-pyridylphospho­nato N-oxide-κ2O1,O2)cobalt(II)

aDepartment of Chemistry & Materials Engineering, Changshu Institute of Technology, Changshu, 215500 Jiangsu, People's Republic of China
*Correspondence e-mail: myschem@126.com

(Received 22 October 2008; accepted 10 November 2008; online 13 November 2008)

In the title complex, [Co(C5H5NO4P)2(H2O)2], the CoII ion, which lies on a crystallographic inversion center, is coordin­ated by four O atoms from two bidentate 2-phospho­nato­pyridine N-oxide ligands and two O atoms from two water ligands in a slightly distorted octa­hedral environment. Mol­ecules are inter­linked by three O—H⋯O hydrogen bonds and one weak C—H⋯O inter­action, forming a three-dimensional supra­molecular structure.

Related literature

For new open frameworks based on metal pyridylphospho­nates, see: Ayyappan et al. (2001[Ayyappan, P., Evans, O. R., Foxman, B. M., Wheeler, K. A., Warren, T. H. & Lin, W.-B. (2001). Inorg. Chem. 40, 5954-5961.]). For two-dimensional Cu-phospho­nates, see: Ma et al. (2006[Ma, Y.-S., Song, Y., Du, W.-X., Li, Y.-Z. & Zheng, L.-M. (2006). Dalton Trans. pp. 3228-3235.]). For one-dimensional Cu-phospho­nates containing bridging ligands, see: Ma et al. (2007[Ma, Y.-S., Wang, T.-W., Li, Y.-Z. & Zheng, L.-M. (2007). Inorg. Chim. Acta, 360, 4117-4124.]). For catalytic and magnetic properties of metal phospho­nates, see: Cao et al. (1992[Cao, G., Hong, H. & Mallouk, T. E. (1992). Acc. Chem. Res. 25, 420-427.]). For the layered structures of monophospho­nic acids and transition metal ions, see Clearfield (1998[Clearfield, A. (1998). Prog. Inorg. Chem. 47, 371-510.]). For a tetra­aqua-Co(II)-4-hydroxy­pyridine-2,6-dicarboxyl­ate structure, see: Cui et al. (2006[Cui, J.-Z., Zhang, H., Lin, T., Kang, H.-J. & Gao, H.-L. (2006). Acta Cryst. E62, m2499-m2501.]). For weak C—H⋯O hydrogen-bonding contacts, see: Desiraju & Steiner (2001[Desiraju, G. R. & Steiner, T. (2001). The Weak Hydrogen Bond in Structural Chemistry and Biology, pp. 29-121. IUCr Monograph on Crystallography, No. 9. Oxford University Press.]). For the synthesis of the ligand (2-pyridyl-N-oxide)phospho­nic acid, see: McCabe et al. (1987[McCabe, D. J., Russell, A. A., Karthikeyan, S., Paine, R. T., Ryan, R. R. & Smith, B. (1987). Inorg. Chem. 26, 1230-1235.]).

[Scheme 1]

Experimental

Crystal data
  • [Co(C5H5NO4P)2(H2O)2]

  • Mr = 443.10

  • Monoclinic, P 21 /n

  • a = 4.7899 (10) Å

  • b = 12.075 (2) Å

  • c = 14.162 (3) Å

  • β = 99.51 (3)°

  • V = 807.8 (3) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 1.32 mm−1

  • T = 293 (2) K

  • 0.5 × 0.3 × 0.2 mm

Data collection
  • Rigaku SCX mini diffractometer

  • Absorption correction: multi-scan (CrystalClear; Rigaku, 2005[Rigaku (2005). CrystalClear. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.625, Tmax = 0.766

  • 8068 measured reflections

  • 1848 independent reflections

  • 1373 reflections with I > 2σ(I)

  • Rint = 0.083

Refinement
  • R[F2 > 2σ(F2)] = 0.051

  • wR(F2) = 0.109

  • S = 1.05

  • 1848 reflections

  • 127 parameters

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

  • Δρmax = 0.39 e Å−3

  • Δρmin = −0.45 e Å−3

Table 1
Selected geometric parameters (Å, °)

Co1—O1 2.084 (2)
Co1—O1W 2.099 (3)
Co1—O4 2.131 (2)
O1—Co1—O1W 89.93 (11)
O1—Co1—O4 87.91 (9)
O1W—Co1—O4 91.55 (10)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1W—H1WB⋯O1i 0.77 (4) 2.15 (5) 2.803 (4) 142 (4)
O3—H3A⋯O2ii 0.85 (4) 1.68 (4) 2.516 (3) 171 (4)
O1W—H1WA⋯O4ii 0.77 (4) 2.00 (4) 2.719 (4) 155 (4)
C3—H3⋯O2iii 0.93 2.52 3.449 (5) 178
Symmetry codes: (i) -x+1, -y, -z+1; (ii) x+1, y, z; (iii) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}].

Data collection: CrystalClear (Rigaku, 2005[Rigaku (2005). CrystalClear. Rigaku Corporation, Tokyo, Japan.]); cell refinement: CrystalClear; data reduction: CrystalClear; 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/PC (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL/PC and PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]).

Supporting information


Comment top

The chemistry of metal phosphonates has received an increasing attention in recent years for their new architectures and properties in catalysis, ion exchange and magnetic materials (Cao et al., 1992). It has been well known that the monophosphonic acid RPO3H2, where R represents an alkyl or aryl group, prefer to form layered structures with transition metal ions (Clearfield 1998). There are some metal phosphonates reported during the past several years which contain pyridyl groups (Ayyappan et al. (2001); Ma et al. (2006); Ma et al. (2007). The present paper is concerned with the crystal structure of a new cobalt phosphonate complex with a (2-pyridyl-N-oxide)phosphonate ligand.

The asymmetric unit contains half of the [Co(C5H4NOPO3H)2(H2O)2] molecule. As shown in Fig. 1, atom Co1 lies on an inversion centre and is coordinated by four O atoms [O1, O1i, O4 and O4i] from two ligands, and two O atoms from two aqua ligands, thereby forming a slightly distorted CoO6 octahedral coordination geometry. The Co1—O1 and the Co1—O4 distances (Table 1) are close to the value observed in [CoL2(H2O)4] [2.0653 (12) Å, and the Co—O(H2O) distance in the title structure is close to the value observed in the Co-tetraaqua compound [2.0764 (13) Å with L = 4-hydroxypyridine-2,6-dicarboxylate (Cui et al., 2006)] (Table 1). The cisoid angles of CoO6 (Table 1) are close to 90°. The phosphonate serves as a chelating ligand using one pyridyl N-oxide acceptor O atom and one phosphonate oxygen atom. One phosphonate oxygen is protonated with the P1—O3 distance 1.560 (3) Å.

In the complex, three classic intermolecular O—H···O hydrogen-bonds exist between the water molecule and a phosphonate O atom, the water molecule and a pyridyl N-oxide acceptor O atom, and between two phosphonate O atoms (Fig. 1, Table 2). Thus, the molecules are interlinked by these hydrogen bonds, forming a one-dimensional chain structure along the a-axis (Fig.2). Additionally, weak intermolecular C—H···O hydrogen bonding contacts (Desiraju & Steiner, 2001) link these chains to form a three-dimensional supramolecular network (Fig. 3).

Related literature top

For new open frameworks based on metal pyridylphosphonates, see: Ayyappan et al. (2001). For two-dimensional Cu-phosphonates, see: Ma et al. (2006). For one-dimensional Cu-phosphonates containing bridging ligands, see: Ma et al. (2007). For catalytic and magnetic properties of metal phosphonates, see: Cao et al. (1992). For the layered structures of monophosphonic acids and transition metal ions, see Clearfield (1998). For a tetraaqua-Co(II)-4-hydroxypyridine-2,6-dicarboxylate structure, see: Cui et al. (2006). For weak C—H···O hydrogen-bonding contacts, see: Desiraju & Steiner (2001). For the synthesis of the ligand (2-pyridyl-N-oxide)phosphonic acid, see: McCabe et al. (1987).

Experimental top

The synthesis of the ligand (2-pyridyl-N-oxide)phosphonic acid, see: McCabe et al. (1987). The (2-pyridyl-N-oxide)phosphonic acid (0.0176 g, 0.1 mmol) was dissolved in distilled water (5 ml), and was added a solution of Co(NO3)2.6H2O (0.0240 g, 0.01 mmol) in distilled water (2 ml). The mixture was stirred at room temperature for 5 h and then filtered. Slow evaporation of the solvent gave pink crystals. (Yield 45%).

Refinement top

Carbon-bound H atoms were positioned geometrically (C—H = 0.93 Å), and were included in the refinement in the riding mode approximation, with Uiso(H) = 1.2Ueq(C). The water H atoms and P—O—H H atom were located in a difference Fourier map and restrained to 0.77 (4) Å and 0.85 (4) Å, respectively, with Uiso(H) refined between 1.0 and 1.8Ueq(O).

Computing details top

Data collection: CrystalClear (Rigaku, 2005); cell refinement: CrystalClear (Rigaku, 2005); data reduction: CrystalClear (Rigaku, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL/PC (Sheldrick, 2008); software used to prepare material for publication: SHELXTL/PC (Sheldrick, 2008) and PLATON (Spek, 2003).

Figures top
[Figure 1] Fig. 1. A view of the compound with the atomic numbering scheme. Displacement ellipsoids were drawn at the 40% probability level. [Symmetry code i = (-x, -y, -z + 1)]
[Figure 2] Fig. 2. One-dimensional supramolecular chain structure with classic O—H···O hydrogen bonds shown with dashed lines, running along the a axis.
[Figure 3] Fig. 3. The cell packing diagram indicating weak C—H···O links with dashed lines, viewed down the a axis.
Diaquabis(2-pyridylphosphonato N-oxide-κ2O1,O2)cobalt(II) top
Crystal data top
[Co(C5H5NO4P)2(H2O)2]F(000) = 450
Mr = 443.10Dx = 1.822 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 6955 reflections
a = 4.7899 (10) Åθ = 3.4–27.7°
b = 12.075 (2) ŵ = 1.32 mm1
c = 14.162 (3) ÅT = 293 K
β = 99.51 (3)°Needle, pink
V = 807.8 (3) Å30.5 × 0.3 × 0.2 mm
Z = 2
Data collection top
Rigaku MACHINE?
diffractometer
1848 independent reflections
Radiation source: fine-focus sealed tube1373 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.083
Detector resolution: 13.6612 pixels mm-1θmax = 27.5°, θmin = 3.4°
dtfind.ref scansh = 66
Absorption correction: multi-scan
(CrystalClear; Rigaku, 2005)
k = 1515
Tmin = 0.625, Tmax = 0.766l = 1818
8068 measured reflections
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)] = 0.051Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.109H atoms treated by a mixture of independent and constrained refinement
S = 1.05 w = 1/[σ2(Fo2) + (0.0457P)2 + 0.1404P]
where P = (Fo2 + 2Fc2)/3
1848 reflections(Δ/σ)max < 0.001
127 parametersΔρmax = 0.39 e Å3
0 restraintsΔρmin = 0.45 e Å3
Crystal data top
[Co(C5H5NO4P)2(H2O)2]V = 807.8 (3) Å3
Mr = 443.10Z = 2
Monoclinic, P21/nMo Kα radiation
a = 4.7899 (10) ŵ = 1.32 mm1
b = 12.075 (2) ÅT = 293 K
c = 14.162 (3) Å0.5 × 0.3 × 0.2 mm
β = 99.51 (3)°
Data collection top
Rigaku MACHINE?
diffractometer
1848 independent reflections
Absorption correction: multi-scan
(CrystalClear; Rigaku, 2005)
1373 reflections with I > 2σ(I)
Tmin = 0.625, Tmax = 0.766Rint = 0.083
8068 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0510 restraints
wR(F2) = 0.109H atoms treated by a mixture of independent and constrained refinement
S = 1.05Δρmax = 0.39 e Å3
1848 reflectionsΔρmin = 0.45 e Å3
127 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
xyzUiso*/Ueq
Co10.00000.00000.50000.0251 (2)
P10.06589 (18)0.23457 (7)0.41631 (6)0.0247 (2)
O10.2057 (5)0.14984 (17)0.48661 (15)0.0265 (5)
O20.1949 (5)0.2903 (2)0.43729 (17)0.0367 (6)
O30.2811 (5)0.3247 (2)0.39564 (18)0.0328 (6)
H3A0.455 (9)0.307 (3)0.406 (3)0.055 (14)*
O40.2925 (5)0.0442 (2)0.37548 (16)0.0326 (6)
O1W0.2669 (6)0.0782 (3)0.4170 (2)0.0317 (6)
H1WA0.362 (8)0.043 (3)0.389 (3)0.031 (12)*
H1WB0.362 (9)0.120 (4)0.449 (3)0.057 (17)*
N10.1928 (6)0.0750 (2)0.29606 (19)0.0281 (7)
C10.0157 (7)0.1641 (3)0.3010 (2)0.0273 (8)
C20.0908 (8)0.1928 (3)0.2193 (3)0.0365 (9)
H20.21410.25250.22100.044*
C30.0168 (9)0.1342 (3)0.1355 (3)0.0450 (10)
H30.09100.15340.08110.054*
C40.1695 (9)0.0462 (4)0.1332 (3)0.0465 (11)
H40.22570.00710.07670.056*
C50.2703 (9)0.0173 (3)0.2146 (3)0.0407 (10)
H50.39300.04260.21380.049*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Co10.0192 (4)0.0303 (4)0.0261 (4)0.0024 (3)0.0050 (3)0.0041 (3)
P10.0175 (5)0.0272 (5)0.0299 (5)0.0009 (4)0.0049 (4)0.0017 (4)
O10.0208 (12)0.0281 (12)0.0301 (13)0.0053 (10)0.0031 (10)0.0049 (10)
O20.0216 (14)0.0389 (15)0.0494 (16)0.0026 (12)0.0056 (12)0.0042 (12)
O30.0177 (14)0.0330 (14)0.0464 (16)0.0028 (12)0.0010 (12)0.0074 (11)
O40.0244 (14)0.0436 (15)0.0301 (13)0.0085 (11)0.0050 (11)0.0067 (11)
O1W0.0271 (15)0.0354 (16)0.0339 (16)0.0008 (14)0.0084 (13)0.0033 (13)
N10.0279 (16)0.0325 (16)0.0232 (15)0.0009 (14)0.0020 (12)0.0032 (12)
C10.0207 (18)0.0320 (19)0.0288 (18)0.0021 (16)0.0033 (15)0.0034 (15)
C20.035 (2)0.040 (2)0.037 (2)0.0009 (18)0.0113 (18)0.0096 (17)
C30.056 (3)0.053 (3)0.028 (2)0.011 (2)0.0147 (19)0.0060 (18)
C40.062 (3)0.044 (2)0.031 (2)0.010 (2)0.002 (2)0.0053 (18)
C50.046 (3)0.037 (2)0.037 (2)0.0031 (19)0.0016 (19)0.0040 (17)
Geometric parameters (Å, º) top
Co1—O12.084 (2)O1W—H1WA0.77 (4)
Co1—O1i2.084 (2)O1W—H1WB0.77 (4)
Co1—O1Wi2.099 (3)N1—C51.346 (4)
Co1—O1W2.099 (3)N1—C11.365 (4)
Co1—O42.131 (2)C1—C21.383 (5)
Co1—O4i2.131 (2)C2—C31.377 (5)
P1—O21.491 (2)C2—H20.9300
P1—O11.505 (2)C3—C41.384 (6)
P1—O31.560 (3)C3—H30.9300
P1—C11.826 (3)C4—C51.367 (5)
O3—H3A0.85 (4)C4—H40.9300
O4—N11.345 (3)C5—H50.9300
O1—Co1—O1i180.0N1—O4—Co1119.04 (18)
O1—Co1—O1Wi90.07 (11)Co1—O1W—H1WA120 (3)
O1i—Co1—O1Wi89.93 (11)Co1—O1W—H1WB108 (3)
O1—Co1—O1W89.93 (11)H1WA—O1W—H1WB108 (4)
O1i—Co1—O1W90.07 (11)O4—N1—C5119.2 (3)
O1Wi—Co1—O1W180.000 (1)O4—N1—C1118.6 (3)
O1—Co1—O487.91 (9)C5—N1—C1122.2 (3)
O1i—Co1—O492.09 (9)N1—C1—C2117.8 (3)
O1Wi—Co1—O488.45 (10)N1—C1—P1116.9 (2)
O1W—Co1—O491.55 (10)C2—C1—P1125.3 (3)
O1—Co1—O4i92.09 (9)C3—C2—C1120.9 (4)
O1i—Co1—O4i87.91 (9)C3—C2—H2119.5
O1Wi—Co1—O4i91.55 (10)C1—C2—H2119.5
O1W—Co1—O4i88.45 (10)C2—C3—C4119.2 (4)
O4—Co1—O4i180.00 (9)C2—C3—H3120.4
O2—P1—O1118.07 (14)C4—C3—H3120.4
O2—P1—O3108.89 (15)C5—C4—C3119.5 (4)
O1—P1—O3111.28 (14)C5—C4—H4120.2
O2—P1—C1109.02 (15)C3—C4—H4120.2
O1—P1—C1106.32 (14)N1—C5—C4120.3 (4)
O3—P1—C1101.99 (15)N1—C5—H5119.9
P1—O1—Co1119.01 (13)C4—C5—H5119.9
P1—O3—H3A117 (3)
O2—P1—O1—Co168.83 (18)O4—N1—C1—P10.7 (4)
O3—P1—O1—Co1164.20 (13)C5—N1—C1—P1179.3 (3)
C1—P1—O1—Co153.93 (18)O2—P1—C1—N168.0 (3)
O1Wi—Co1—O1—P178.04 (16)O1—P1—C1—N160.3 (3)
O1W—Co1—O1—P1101.96 (16)O3—P1—C1—N1176.9 (2)
O4—Co1—O1—P110.41 (15)O2—P1—C1—C2113.0 (3)
O4i—Co1—O1—P1169.59 (15)O1—P1—C1—C2118.7 (3)
O1—Co1—O4—N152.1 (2)O3—P1—C1—C22.0 (3)
O1i—Co1—O4—N1127.9 (2)N1—C1—C2—C30.9 (5)
O1Wi—Co1—O4—N1142.2 (2)P1—C1—C2—C3179.9 (3)
O1W—Co1—O4—N137.8 (2)C1—C2—C3—C40.8 (6)
Co1—O4—N1—C5121.0 (3)C2—C3—C4—C51.8 (6)
Co1—O4—N1—C159.0 (3)O4—N1—C5—C4179.3 (3)
O4—N1—C1—C2178.3 (3)C1—N1—C5—C40.7 (5)
C5—N1—C1—C21.7 (5)C3—C4—C5—N11.1 (6)
Symmetry code: (i) x, y, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1WB···O1ii0.77 (4)2.15 (5)2.803 (4)142 (4)
O3—H3A···O2iii0.85 (4)1.68 (4)2.516 (3)171 (4)
O1W—H1WA···O4iii0.77 (4)2.00 (4)2.719 (4)155 (4)
C3—H3···O2iv0.932.523.449 (5)178
Symmetry codes: (ii) x+1, y, z+1; (iii) x+1, y, z; (iv) x+1/2, y+1/2, z1/2.

Experimental details

Crystal data
Chemical formula[Co(C5H5NO4P)2(H2O)2]
Mr443.10
Crystal system, space groupMonoclinic, P21/n
Temperature (K)293
a, b, c (Å)4.7899 (10), 12.075 (2), 14.162 (3)
β (°) 99.51 (3)
V3)807.8 (3)
Z2
Radiation typeMo Kα
µ (mm1)1.32
Crystal size (mm)0.5 × 0.3 × 0.2
Data collection
DiffractometerRigaku MACHINE?
diffractometer
Absorption correctionMulti-scan
(CrystalClear; Rigaku, 2005)
Tmin, Tmax0.625, 0.766
No. of measured, independent and
observed [I > 2σ(I)] reflections
8068, 1848, 1373
Rint0.083
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.051, 0.109, 1.05
No. of reflections1848
No. of parameters127
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.39, 0.45

Computer programs: CrystalClear (Rigaku, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL/PC (Sheldrick, 2008) and PLATON (Spek, 2003).

Selected geometric parameters (Å, º) top
Co1—O12.084 (2)Co1—O42.131 (2)
Co1—O1W2.099 (3)
O1—Co1—O1W89.93 (11)O1W—Co1—O491.55 (10)
O1—Co1—O487.91 (9)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1WB···O1i0.77 (4)2.15 (5)2.803 (4)142 (4)
O3—H3A···O2ii0.85 (4)1.68 (4)2.516 (3)171 (4)
O1W—H1WA···O4ii0.77 (4)2.00 (4)2.719 (4)155 (4)
C3—H3···O2iii0.932.523.449 (5)178
Symmetry codes: (i) x+1, y, z+1; (ii) x+1, y, z; (iii) x+1/2, y+1/2, z1/2.
 

Acknowledgements

This work was supported by a start-up grant from CSLG (No. KY10657).

References

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Volume 64| Part 12| December 2008| Pages m1550-m1551
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