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

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Bis[2-(1H-benzimidazol-2-yl)acetato-κ2N3,O]bis­­(ethanol-κO)nickel(II)

aZhongshan Polytechnic, Zhongshan, Guangdong 528404, People's Republic of China
*Correspondence e-mail: Niejianhua.crystal@yahoo.com

(Received 26 October 2012; accepted 31 October 2012; online 7 November 2012)

In the title compound, [Ni(C9H7N2O2)2(C2H5OH)2], the NiII ion is situated on an inversion center and is coordinated by two N and two O atoms from two 2-(1H-benzimidazol-2-yl)acetate (L) ligands and by two O atoms from two ethanol ligands in a distorted octa­hedral geometry. In the L ligand, the acetate group deviates significantly from the benzimidazole plane, the C—C—C—O(coordinating) torsion angle being 34.2 (5)°. In the crystal, O—H⋯O and N—H⋯O hydrogen bonds link the mol­ecules into a two-dimensional supra­molecular network parallel to the bc plane.

Related literature

For related structures, see: Chen et al. (2010[Chen, W., Yang, B. Q., Ma, S. S., Shao, X. X. & Jiang, S. (2010). Chin. J. Struct. Chem. 29, 1241-1249.]); Gao et al. (2011[Gao, J., Wang, J. & Dai, C. (2011). Acta Cryst. E67, m75.]); Guo et al. (2007[Guo, Z. G., Li, X. J., Gao, S. Y. & Li, Y. F. (2007). J. Mol. Struct. 846, 123-127.]); Peng et al. (2010[Peng, G., Qiu, Y. C., Liu, Z. H., Liu, B. & Deng, H. (2010). Cryst. Growth Des. 10, 114-121.]).

[Scheme 1]

Experimental

Crystal data
  • [Ni(C9H7N2O2)2(C2H6O)2]

  • Mr = 501.18

  • Monoclinic, P 21 /c

  • a = 10.441 (5) Å

  • b = 9.639 (4) Å

  • c = 11.480 (5) Å

  • β = 98.956 (6)°

  • V = 1141.3 (9) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.90 mm−1

  • T = 298 K

  • 0.28 × 0.26 × 0.23 mm

Data collection
  • Bruker APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2004[Bruker (2004). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.788, Tmax = 0.821

  • 6022 measured reflections

  • 2231 independent reflections

  • 1411 reflections with I > 2σ(I)

  • Rint = 0.061

Refinement
  • R[F2 > 2σ(F2)] = 0.049

  • wR(F2) = 0.107

  • S = 1.04

  • 2231 reflections

  • 152 parameters

  • H-atom parameters constrained

  • Δρmax = 0.36 e Å−3

  • Δρmin = −0.45 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O3—H3A⋯O2i 0.85 1.96 2.672 (3) 141
N2—H2A⋯O2ii 0.86 1.93 2.788 (4) 173
Symmetry codes: (i) [x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]; (ii) [-x+1, y+{\script{1\over 2}}, -z-{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2004[Bruker (2004). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2004[Bruker (2004). APEX2, SAINT and SADABS. Bruker AXS 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: ORTEPIII (Burnett & Johnson, 1996[Burnett, M. N. & Johnson, C. K. (1996). ORTEPIII. Report ORNL-6895. Oak Ridge National Laboratory, Tennessee, USA.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

Multidentate ligands containing N donors and carboxylic groups are often employed to construct new metal coordination polymers with different structures (Chen et al., 2010; Gao et al., 2011; Guo et al., 2007; Peng et al., 2010). The main reason is that they have various coordination modes and can form high-dimensional polymers through hydrogen-bonding interactions in the process of self-assembly. In this work, we chose 2-(1H-benzimidazol-2-yl)acetic acid (HL), which contains two N atoms of an imidazole group and one carboxylate group, as the building block to prepare new metal coordination polymers. To date, only three mononuclear complexes based on the HL ligand have been reported (Chen et al.,2010). In this paper, we report the synthesis and structure of the title compound, (I), obtained by the solvothermal reaction of NiCl2 and HL ligand.

In (I) (Fig. 1), the Ni(II) ion is coordinated by two N and two O atoms from two bidentate chelating L ligands and two O atoms from two ethanol molecules in a distorted octahedral geometry. The Ni—N bond length is equal to 2.055 (3) Å, and the Ni—O distances vary from 2.037 (3) to 2.107 (2) Å. In the crystal, intermolecular O—H···O and N–H···O hydrogen bonds (Table1) involving the carboxylate O atoms, the imidazole N atoms and the coordinated ethanol O atoms link the molecules into a two-dimensional supramolecular network parallel to the bc plane (Fig. 2).

Related literature top

For related structures, see: Chen et al. (2010); Gao et al. (2011); Guo et al. (2007); Peng et al. (2010).

Experimental top

A mixture of NiCl2 (0.40 mmol), HL (0.40 mmol) and 8 ml C2H5OH was sealed into a 15 ml Teflon-lined stainless steel autoclave and then heated at 373 K for 72 h under autogenous pressure. After cooling to room temperature at a rate of 2 K /h, green block crystals of the title compound suitable for X-ray diffraction were obtained (yield: 35%).

Refinement top

C– and N-bound H atoms were positioned geometrically and refined using a riding model, with C—H = 0.93–0.97 Å, N—H = 0.86 Å and with Uiso(H) = 1.2(1.5 for methyl)Ueq(C), Uiso(H) = 1.2Ueq(N). Hydroxy H atoms were located in a difference Fourier map and refined as riding, with O—H = 0.85 Å and Uiso(H)= 1.2Ueq(O).

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) with displacement ellipsoids drawn at the 30% probability level [symmetry code\: (i) 1 - x, -y, -z].
[Figure 2] Fig. 2. A portion of the crystal packing, showing the two-dimensional supramolecular network. Hydrogen bonds are shown as dashed lines.
Bis[2-(1H-benzimidazol-2-yl)acetato- κ2N3,O]bis(ethanol-κO)nickel(II) top
Crystal data top
[Ni(C9H7N2O2)2(C2H6O)2]F(000) = 524
Mr = 501.18Dx = 1.458 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1078 reflections
a = 10.441 (5) Åθ = 2.8–21.1°
b = 9.639 (4) ŵ = 0.90 mm1
c = 11.480 (5) ÅT = 298 K
β = 98.956 (6)°Block, green
V = 1141.3 (9) Å30.28 × 0.26 × 0.23 mm
Z = 2
Data collection top
Bruker APEXII CCD area-detector
diffractometer
2231 independent reflections
Radiation source: fine-focus sealed tube1411 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.061
phi and ω scansθmax = 26.0°, θmin = 2.8°
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
h = 812
Tmin = 0.788, Tmax = 0.821k = 1111
6022 measured reflectionsl = 1414
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)] = 0.049Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.107H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0364P)2]
where P = (Fo2 + 2Fc2)/3
2231 reflections(Δ/σ)max < 0.001
152 parametersΔρmax = 0.36 e Å3
0 restraintsΔρmin = 0.45 e Å3
Crystal data top
[Ni(C9H7N2O2)2(C2H6O)2]V = 1141.3 (9) Å3
Mr = 501.18Z = 2
Monoclinic, P21/cMo Kα radiation
a = 10.441 (5) ŵ = 0.90 mm1
b = 9.639 (4) ÅT = 298 K
c = 11.480 (5) Å0.28 × 0.26 × 0.23 mm
β = 98.956 (6)°
Data collection top
Bruker APEXII CCD area-detector
diffractometer
2231 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
1411 reflections with I > 2σ(I)
Tmin = 0.788, Tmax = 0.821Rint = 0.061
6022 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0490 restraints
wR(F2) = 0.107H-atom parameters constrained
S = 1.04Δρmax = 0.36 e Å3
2231 reflectionsΔρmin = 0.45 e Å3
152 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
Ni10.50000.00000.00000.0295 (2)
C70.5632 (4)0.2871 (4)0.0656 (3)0.0303 (9)
C10.7327 (4)0.3710 (4)0.0516 (3)0.0372 (10)
C60.7025 (4)0.2385 (4)0.0887 (3)0.0310 (9)
C80.4525 (4)0.2834 (4)0.1641 (3)0.0357 (10)
H8A0.46550.35590.21970.043*
H8B0.37410.30590.13250.043*
C50.7763 (4)0.1803 (4)0.1874 (4)0.0451 (11)
H50.75680.09290.21410.054*
C40.8787 (4)0.2548 (5)0.2444 (4)0.0564 (13)
H40.92940.21780.31090.068*
C20.8367 (4)0.4466 (4)0.1082 (4)0.0538 (12)
H20.85680.53410.08210.065*
C30.9081 (4)0.3863 (4)0.2039 (4)0.0574 (13)
H30.97890.43400.24400.069*
C90.4305 (4)0.1481 (4)0.2311 (3)0.0302 (9)
O20.3884 (3)0.1537 (2)0.3388 (2)0.0435 (7)
O10.4545 (2)0.0357 (2)0.1765 (2)0.0357 (7)
N10.5959 (3)0.1869 (3)0.0125 (3)0.0300 (8)
N20.6410 (3)0.3986 (3)0.0456 (3)0.0382 (8)
H2A0.63470.47390.08640.046*
O30.3382 (2)0.1147 (2)0.0343 (2)0.0367 (7)
H3A0.33980.20250.04160.044*
C100.2225 (5)0.0637 (5)0.0670 (5)0.0627 (14)
H10A0.23860.04010.15020.075*
H10B0.19840.02090.02330.075*
C110.1146 (5)0.1594 (6)0.0467 (6)0.112 (2)
H11A0.13640.24270.09130.168*
H11B0.03970.11750.07100.168*
H11C0.09620.18170.03580.168*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Ni10.0404 (5)0.0212 (4)0.0268 (4)0.0017 (3)0.0044 (3)0.0004 (3)
C70.039 (3)0.022 (2)0.031 (2)0.0052 (18)0.0072 (18)0.0016 (17)
C10.045 (3)0.029 (2)0.037 (2)0.002 (2)0.003 (2)0.0036 (18)
C60.035 (3)0.027 (2)0.031 (2)0.0018 (18)0.0041 (19)0.0012 (17)
C80.050 (3)0.024 (2)0.031 (2)0.0009 (19)0.000 (2)0.0009 (17)
C50.052 (3)0.037 (2)0.044 (3)0.003 (2)0.002 (2)0.002 (2)
C40.057 (4)0.054 (3)0.051 (3)0.001 (3)0.013 (2)0.000 (2)
C20.059 (3)0.038 (3)0.060 (3)0.015 (2)0.002 (3)0.004 (2)
C30.053 (3)0.049 (3)0.065 (3)0.014 (3)0.007 (3)0.015 (3)
C90.032 (2)0.027 (2)0.032 (2)0.0036 (18)0.0043 (18)0.0002 (18)
O20.071 (2)0.0274 (15)0.0280 (16)0.0006 (14)0.0061 (14)0.0026 (12)
O10.0565 (19)0.0214 (14)0.0283 (15)0.0004 (12)0.0041 (12)0.0010 (11)
N10.038 (2)0.0250 (17)0.0270 (18)0.0005 (15)0.0042 (15)0.0012 (14)
N20.051 (2)0.0258 (18)0.037 (2)0.0079 (16)0.0018 (17)0.0063 (15)
O30.0414 (18)0.0256 (14)0.0448 (17)0.0020 (13)0.0118 (13)0.0006 (12)
C100.058 (4)0.051 (3)0.083 (4)0.007 (3)0.025 (3)0.014 (3)
C110.054 (4)0.089 (5)0.195 (8)0.013 (4)0.025 (4)0.012 (5)
Geometric parameters (Å, º) top
Ni1—O1i2.037 (3)C5—H50.9300
Ni1—O12.037 (3)C4—C31.400 (6)
Ni1—N1i2.055 (3)C4—H40.9300
Ni1—N12.055 (3)C2—C31.358 (6)
Ni1—O3i2.107 (2)C2—H20.9300
Ni1—O32.107 (2)C3—H30.9300
C7—N11.325 (4)C9—O21.247 (4)
C7—N21.346 (4)C9—O11.257 (4)
C7—C81.487 (5)N2—H2A0.8600
C1—N21.379 (5)O3—C101.409 (5)
C1—C21.384 (5)O3—H3A0.8500
C1—C61.398 (5)C10—C111.447 (6)
C6—C51.386 (5)C10—H10A0.9700
C6—N11.395 (5)C10—H10B0.9700
C8—C91.514 (5)C11—H11A0.9600
C8—H8A0.9700C11—H11B0.9600
C8—H8B0.9700C11—H11C0.9600
C5—C41.367 (5)
O1i—Ni1—O1180.0C5—C4—H4119.6
O1i—Ni1—N1i87.54 (10)C3—C4—H4119.6
O1—Ni1—N1i92.46 (10)C3—C2—C1116.5 (4)
O1i—Ni1—N192.46 (10)C3—C2—H2121.7
O1—Ni1—N187.54 (10)C1—C2—H2121.7
N1i—Ni1—N1180.0C2—C3—C4122.3 (4)
O1i—Ni1—O3i91.58 (10)C2—C3—H3118.8
O1—Ni1—O3i88.42 (10)C4—C3—H3118.8
N1i—Ni1—O3i85.58 (11)O2—C9—O1123.0 (3)
N1—Ni1—O3i94.42 (11)O2—C9—C8117.9 (3)
O1i—Ni1—O388.42 (10)O1—C9—C8119.1 (3)
O1—Ni1—O391.58 (10)C9—O1—Ni1129.7 (2)
N1i—Ni1—O394.42 (11)C7—N1—C6105.1 (3)
N1—Ni1—O385.58 (11)C7—N1—Ni1121.3 (2)
O3i—Ni1—O3180.0C6—N1—Ni1133.5 (2)
N1—C7—N2112.5 (3)C7—N2—C1107.9 (3)
N1—C7—C8125.8 (3)C7—N2—H2A126.0
N2—C7—C8121.7 (3)C1—N2—H2A126.0
N2—C1—C2132.4 (4)C10—O3—Ni1127.8 (2)
N2—C1—C6105.2 (3)C10—O3—H3A109.0
C2—C1—C6122.4 (4)Ni1—O3—H3A122.5
C5—C6—N1131.0 (3)O3—C10—C11114.4 (4)
C5—C6—C1119.7 (4)O3—C10—H10A108.7
N1—C6—C1109.3 (3)C11—C10—H10A108.7
C7—C8—C9116.4 (3)O3—C10—H10B108.7
C7—C8—H8A108.2C11—C10—H10B108.7
C9—C8—H8A108.2H10A—C10—H10B107.6
C7—C8—H8B108.2C10—C11—H11A109.5
C9—C8—H8B108.2C10—C11—H11B109.5
H8A—C8—H8B107.3H11A—C11—H11B109.5
C4—C5—C6118.2 (4)C10—C11—H11C109.5
C4—C5—H5120.9H11A—C11—H11C109.5
C6—C5—H5120.9H11B—C11—H11C109.5
C5—C4—C3120.8 (4)
N2—C1—C6—C5178.9 (3)N2—C7—N1—Ni1177.1 (2)
C2—C1—C6—C51.7 (6)C8—C7—N1—Ni14.1 (5)
N2—C1—C6—N11.4 (4)C5—C6—N1—C7179.3 (4)
C2—C1—C6—N1178.0 (4)C1—C6—N1—C71.1 (4)
N1—C7—C8—C941.6 (5)C5—C6—N1—Ni13.7 (6)
N2—C7—C8—C9139.7 (3)C1—C6—N1—Ni1175.9 (2)
N1—C6—C5—C4178.5 (4)O1i—Ni1—N1—C7154.3 (3)
C1—C6—C5—C41.1 (6)O1—Ni1—N1—C725.7 (3)
C6—C5—C4—C30.1 (7)O3i—Ni1—N1—C7114.0 (3)
N2—C1—C2—C3179.8 (4)O3—Ni1—N1—C766.0 (3)
C6—C1—C2—C31.0 (7)O1i—Ni1—N1—C629.2 (3)
C1—C2—C3—C40.2 (7)O1—Ni1—N1—C6150.8 (3)
C5—C4—C3—C20.8 (7)O3i—Ni1—N1—C662.6 (3)
C7—C8—C9—O2146.1 (4)O3—Ni1—N1—C6117.4 (3)
C7—C8—C9—O134.2 (5)N1—C7—N2—C10.5 (4)
O2—C9—O1—Ni1171.0 (3)C8—C7—N2—C1179.4 (3)
C8—C9—O1—Ni18.7 (5)C2—C1—N2—C7178.1 (4)
N1i—Ni1—O1—C9145.8 (3)C6—C1—N2—C71.2 (4)
N1—Ni1—O1—C934.2 (3)O1i—Ni1—O3—C1073.1 (3)
O3i—Ni1—O1—C9128.7 (3)O1—Ni1—O3—C10106.9 (3)
O3—Ni1—O1—C951.3 (3)N1i—Ni1—O3—C1014.3 (3)
N2—C7—N1—C60.4 (4)N1—Ni1—O3—C10165.7 (3)
C8—C7—N1—C6178.4 (4)Ni1—O3—C10—C11160.5 (4)
Symmetry code: (i) x+1, y, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3A···O2ii0.851.962.672 (3)141
N2—H2A···O2iii0.861.932.788 (4)173
Symmetry codes: (ii) x, y+1/2, z+1/2; (iii) x+1, y+1/2, z1/2.

Experimental details

Crystal data
Chemical formula[Ni(C9H7N2O2)2(C2H6O)2]
Mr501.18
Crystal system, space groupMonoclinic, P21/c
Temperature (K)298
a, b, c (Å)10.441 (5), 9.639 (4), 11.480 (5)
β (°) 98.956 (6)
V3)1141.3 (9)
Z2
Radiation typeMo Kα
µ (mm1)0.90
Crystal size (mm)0.28 × 0.26 × 0.23
Data collection
DiffractometerBruker APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2004)
Tmin, Tmax0.788, 0.821
No. of measured, independent and
observed [I > 2σ(I)] reflections
6022, 2231, 1411
Rint0.061
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.049, 0.107, 1.04
No. of reflections2231
No. of parameters152
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.36, 0.45

Computer programs: APEX2 (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEPIII (Burnett & Johnson, 1996) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3A···O2i0.851.962.672 (3)140.5
N2—H2A···O2ii0.861.932.788 (4)172.6
Symmetry codes: (i) x, y+1/2, z+1/2; (ii) x+1, y+1/2, z1/2.
 

Acknowledgements

The authors gratefully acknowledge the Science and Technology Research Project of Zhongshan City (grant No. 20114 A256).

References

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ISSN: 2056-9890
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