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

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N,N,2,4,6-Penta­methyl­anilinium hexa­fluoro­phosphate–1,4,7,10,13,16-hexa­oxa­cyclo­octa­decane (2/1)

aDepartment of Applied Chemistry, Nanjing College of Chemical Technology, Nanjing 210048, People's Republic of China
*Correspondence e-mail: 75104209@qq.com

(Received 26 November 2013; accepted 13 December 2013; online 18 December 2013)

In the title compound, 2C11H18N+·2PF6·C12H24O6, the 18-crown-6 mol­ecule has crystallographically imposed inversion symmetry. In the crystal, it inter­acts with the cation through weak C—H⋯O hydrogen bonds. The cations and anions are further linked via N—H⋯F and C—H⋯F hydrogen bonds, leading to a sandwich structure .

Related literature

For background to the development of ferroelectric pure organic or inorganic compounds, see: Haertling (1999[Haertling, G. H. (1999). J. Am. Ceram. Soc. 82, 797-810.]); Homes et al. (2001[Homes, C. C., Vogt, T., Shapiro, S. M., Wakimoto, S. & Ramirez, A. P. (2001). Science, 293, 673-676.]). For the structure of a related compound, see: Zhang (2013[Zhang, Y. (2013). Acta Cryst. E69, o31.]).

[Scheme 1]

Experimental

Crystal data
  • 2C11H18N+·2PF6·C12H24O6

  • Mr = 882.78

  • Monoclinic, P 21 /c

  • a = 8.9122 (18) Å

  • b = 16.775 (3) Å

  • c = 15.136 (3) Å

  • β = 103.71 (3)°

  • V = 2198.4 (8) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.19 mm−1

  • T = 293 K

  • 0.40 × 0.30 × 0.20 mm

Data collection
  • Rigaku Mercury2 (2x2 bin mode) diffractometer

  • Absorption correction: multi-scan (CrystalClear; Rigaku, 2005[Rigaku (2005). CrystalClear. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.832, Tmax = 1.000

  • 18170 measured reflections

  • 3858 independent reflections

  • 2524 reflections with I > 2σ(I)

  • Rint = 0.053

Refinement
  • R[F2 > 2σ(F2)] = 0.083

  • wR(F2) = 0.195

  • S = 1.20

  • 3858 reflections

  • 253 parameters

  • H-atom parameters constrained

  • Δρmax = 0.49 e Å−3

  • Δρmin = −0.30 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1C⋯F4 0.91 2.38 3.077 (5) 134
C16—H16A⋯O3i 0.96 2.52 3.334 (5) 143
C16—H16B⋯O2ii 0.96 2.51 3.443 (5) 164
C16—H16C⋯O1i 0.96 2.57 3.381 (5) 143
C17—H17B⋯F4 0.96 2.54 3.122 (6) 119
Symmetry codes: (i) x, y-1, z; (ii) -x, -y+1, -z+1.

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 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

As a continuation of our studies on the development of novel ferroelectric pure organic or inorganic compounds (Haertling et al., 1999; Homes et al., 2001), we investigated the physical properties of the title compound. Recently the crystal structure of the strictly related compound N,N,2,4,6-pentamethylanilinium hexafluorophosphate was reported by our group (Zhang, 2013). The dielectric constant of the title compound as a function of the temperature indicates that the permittivity is basically temperature-independent (dielectric constant equaling to 4.1 to 6.1), suggesting that this compound should be not a real ferroelectrics or there may be no distinct phase transition occurring within the measured temperature range. Similarly, below the melting point (180°C) of the compound, the dielectric constant as a function of temperature also goes smoothly, and there is no dielectric anomaly observed (dielectric constant equaling to 4.1 to 6.1). Herein, we report the synthesis and crystal structure of the title compound.

The asymmetric unit of the title compound (Fig. 1) consists of one N,N,2,4,6-pentamethylanilinium cation, one hexafluorophosphate anion and one half of a 1,4,7,10,13,16-hexaoxacyclooctadecane molecule. Bond distances and bond angles are not unusual. In the crystal structure (Fig. 2), the 18-crown-6 molecule interacts with the cation through weak C—H···O hydrogen bonds (Table 1). Cation and anion are further linked via N—H···F and C—H···F hydrogen bonds. Dipole–dipole and van der Waals interactions are effective in stabilizing the molecular packing.

Related literature top

For background to the development of ferroelectric pure organic or inorganic compounds, see: Haertling (1999); Homes et al. (2001). For the structure of a related compound, see: Zhang (2013).

Experimental top

A mixture of N,N,2,4,6-pentamethylbenzenamine (1.36 g, 10 mmol), hexafluorophosphoric acid(1.90 g, 10 mmol) and 1,4,7,10,13,16-hexaoxacyclooctadecane (2.64, 10 mmol) in methanol(30 ml) was stirred until clear. After several days, the title compound was formed and recrystallized from a methanol solution to afford colourless prismatic crystals suitable for X-ray analysis.

Refinement top

H atoms were positioned geometrically and refined using a riding model, with C—H = 0.97 Å, N—H = 0.91 Å, and Uiso(H) = 1.2 Ueq(C, N) or 1.5 Ueq(C) for methyl H atoms

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 (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Perspective view of the title compound, showing the displacement ellipsoids drawn at the 30% probability level. Atoms with the suffix A are generated by symmetry code -x, 2-y, 1-z.
[Figure 2] Fig. 2. Crystal packing of the title compound viewed along the b axis, showing the hydrogen bonding network (dashed lines).
N,N,2,4,6-Pentamethylanilinium hexafluorophosphate–1,4,7,10,13,16-hexaoxacyclooctadecane (2/1) top
Crystal data top
2C11H18N+·2PF6·C12H24O6F(000) = 928
Mr = 882.78Dx = 1.334 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3858 reflections
a = 8.9122 (18) Åθ = 2.6–25.0°
b = 16.775 (3) ŵ = 0.19 mm1
c = 15.136 (3) ÅT = 293 K
β = 103.71 (3)°Prism, colourless
V = 2198.4 (8) Å30.40 × 0.30 × 0.20 mm
Z = 2
Data collection top
Rigaku Mercury2 (2x2 bin mode)
diffractometer
3858 independent reflections
Radiation source: fine-focus sealed tube2524 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.053
Detector resolution: 13.6612 pixels mm-1θmax = 25.0°, θmin = 3.0°
CCD_Profile_fitting scansh = 1010
Absorption correction: multi-scan
(CrystalClear; Rigaku, 2005)
k = 1919
Tmin = 0.832, Tmax = 1.000l = 1717
18170 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)] = 0.083Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.195H-atom parameters constrained
S = 1.20 w = 1/[σ2(Fo2) + (0.0528P)2 + 2.P]
where P = (Fo2 + 2Fc2)/3
3858 reflections(Δ/σ)max = 0.003
253 parametersΔρmax = 0.49 e Å3
0 restraintsΔρmin = 0.30 e Å3
Crystal data top
2C11H18N+·2PF6·C12H24O6V = 2198.4 (8) Å3
Mr = 882.78Z = 2
Monoclinic, P21/cMo Kα radiation
a = 8.9122 (18) ŵ = 0.19 mm1
b = 16.775 (3) ÅT = 293 K
c = 15.136 (3) Å0.40 × 0.30 × 0.20 mm
β = 103.71 (3)°
Data collection top
Rigaku Mercury2 (2x2 bin mode)
diffractometer
3858 independent reflections
Absorption correction: multi-scan
(CrystalClear; Rigaku, 2005)
2524 reflections with I > 2σ(I)
Tmin = 0.832, Tmax = 1.000Rint = 0.053
18170 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0830 restraints
wR(F2) = 0.195H-atom parameters constrained
S = 1.20Δρmax = 0.49 e Å3
3858 reflectionsΔρmin = 0.30 e Å3
253 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
P10.47256 (14)0.24011 (8)0.74636 (8)0.0722 (4)
F60.4805 (5)0.2762 (2)0.6529 (2)0.1280 (12)
F50.3159 (4)0.2840 (2)0.7412 (3)0.1289 (12)
F40.3770 (4)0.16651 (18)0.6942 (2)0.1268 (12)
F30.4597 (5)0.2030 (2)0.8388 (2)0.1461 (15)
F20.5602 (5)0.3133 (2)0.7981 (3)0.1507 (15)
F10.6268 (5)0.1971 (3)0.7510 (3)0.1725 (19)
O30.2823 (3)1.00490 (16)0.45178 (17)0.0589 (7)
O20.1340 (3)0.85340 (16)0.45499 (17)0.0612 (7)
O10.1059 (3)0.85014 (16)0.55077 (17)0.0609 (7)
C60.2987 (5)1.0742 (3)0.4023 (3)0.0651 (11)
H6A0.22761.07220.34290.078*
H6B0.40291.07710.39360.078*
C40.2945 (5)0.8633 (3)0.4624 (3)0.0673 (11)
H4A0.33580.81660.43860.081*
H4B0.34800.86960.52570.081*
C50.3191 (5)0.9355 (3)0.4095 (3)0.0647 (11)
H5A0.42610.93780.40560.078*
H5B0.25480.93210.34820.078*
C20.0682 (5)0.7856 (2)0.5001 (3)0.0616 (11)
H2A0.12490.78990.43710.074*
H2B0.09610.73570.52430.074*
C30.1010 (5)0.7875 (2)0.5061 (3)0.0630 (11)
H3A0.15730.79270.56910.076*
H3B0.13290.73840.48210.076*
C10.2661 (5)0.8535 (3)0.5475 (3)0.0664 (11)
H1A0.29710.80600.57510.080*
H1B0.32470.85600.48480.080*
C70.0742 (4)0.0080 (2)0.7882 (2)0.0501 (9)
N10.1899 (4)0.0220 (2)0.7330 (2)0.0679 (10)
H1C0.19700.07610.73270.081*
C90.1049 (5)0.0657 (3)0.8628 (3)0.0647 (11)
H9A0.15320.11040.87970.078*
C120.0381 (5)0.0678 (2)0.8125 (3)0.0616 (11)
C110.0714 (6)0.0732 (3)0.8639 (3)0.0726 (13)
H11A0.09710.12350.88160.087*
C80.0030 (4)0.0760 (2)0.8112 (2)0.0537 (10)
C100.1433 (5)0.0085 (3)0.8899 (3)0.0675 (12)
C130.0349 (6)0.1585 (2)0.7817 (3)0.0774 (13)
H13A0.02700.19630.80490.116*
H13B0.00990.16110.71640.116*
H13C0.14220.17090.80480.116*
C160.1342 (6)0.0025 (3)0.6344 (3)0.0709 (12)
H16A0.21400.01420.60350.106*
H16B0.04430.03380.60870.106*
H16C0.10850.05310.62770.106*
C170.3506 (5)0.0026 (3)0.7753 (4)0.0873 (15)
H17A0.37740.01420.83770.131*
H17B0.41960.02170.74330.131*
H17C0.35880.05950.77240.131*
C150.1046 (7)0.1451 (3)0.7880 (4)0.1037 (18)
H15A0.05920.18890.81310.156*
H15B0.21440.14520.81230.156*
H15C0.08270.15030.72300.156*
C140.2611 (6)0.0173 (4)0.9466 (3)0.109 (2)
H14A0.29890.03440.95790.164*
H14B0.21370.04231.00340.164*
H14C0.34550.04960.91440.164*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
P10.0737 (8)0.0786 (9)0.0619 (7)0.0147 (7)0.0115 (6)0.0153 (6)
F60.166 (3)0.134 (3)0.090 (2)0.004 (2)0.044 (2)0.010 (2)
F50.105 (2)0.129 (3)0.155 (3)0.044 (2)0.035 (2)0.003 (2)
F40.177 (3)0.088 (2)0.106 (2)0.022 (2)0.017 (2)0.0247 (18)
F30.202 (4)0.166 (4)0.074 (2)0.046 (3)0.041 (2)0.022 (2)
F20.155 (3)0.151 (3)0.140 (3)0.030 (3)0.023 (2)0.065 (3)
F10.126 (3)0.232 (5)0.158 (3)0.101 (3)0.031 (3)0.019 (3)
O30.0604 (17)0.0714 (18)0.0509 (15)0.0010 (14)0.0253 (13)0.0022 (14)
O20.0529 (16)0.0711 (18)0.0599 (16)0.0049 (14)0.0138 (12)0.0084 (14)
O10.0557 (17)0.0676 (18)0.0605 (16)0.0109 (14)0.0164 (13)0.0133 (14)
C60.053 (2)0.090 (3)0.057 (2)0.012 (2)0.0249 (19)0.003 (2)
C40.054 (3)0.079 (3)0.070 (3)0.011 (2)0.019 (2)0.001 (2)
C50.050 (2)0.092 (3)0.058 (2)0.004 (2)0.0234 (19)0.004 (2)
C20.076 (3)0.054 (2)0.054 (2)0.009 (2)0.013 (2)0.0014 (19)
C30.075 (3)0.055 (2)0.056 (2)0.007 (2)0.011 (2)0.003 (2)
C10.061 (3)0.074 (3)0.066 (3)0.019 (2)0.018 (2)0.000 (2)
C70.054 (2)0.059 (2)0.0350 (18)0.0008 (19)0.0063 (16)0.0018 (17)
N10.065 (2)0.083 (3)0.055 (2)0.0083 (18)0.0140 (17)0.0001 (18)
C90.067 (3)0.078 (3)0.046 (2)0.014 (2)0.006 (2)0.008 (2)
C120.081 (3)0.053 (2)0.046 (2)0.001 (2)0.005 (2)0.0007 (19)
C110.089 (3)0.069 (3)0.052 (2)0.019 (3)0.002 (2)0.008 (2)
C80.061 (2)0.055 (2)0.040 (2)0.0030 (19)0.0023 (18)0.0010 (17)
C100.052 (2)0.105 (4)0.040 (2)0.010 (3)0.0013 (18)0.006 (2)
C130.110 (4)0.049 (3)0.075 (3)0.005 (2)0.026 (3)0.001 (2)
C160.087 (3)0.085 (3)0.045 (2)0.004 (2)0.023 (2)0.006 (2)
C170.067 (3)0.090 (4)0.100 (4)0.011 (3)0.010 (3)0.010 (3)
C150.164 (6)0.057 (3)0.091 (4)0.021 (3)0.032 (4)0.001 (3)
C140.073 (3)0.187 (6)0.070 (3)0.025 (4)0.024 (3)0.011 (3)
Geometric parameters (Å, º) top
P1—F11.539 (3)C7—C81.390 (5)
P1—F61.556 (3)C7—N11.492 (5)
P1—F31.560 (3)N1—C171.482 (5)
P1—F21.562 (4)N1—C161.493 (5)
P1—F51.564 (3)N1—H1C0.9100
P1—F41.598 (3)C9—C101.380 (6)
O3—C51.404 (5)C9—C81.385 (6)
O3—C61.409 (5)C9—H9A0.9300
O2—C41.418 (4)C12—C111.389 (6)
O2—C31.419 (4)C12—C151.507 (6)
O1—C21.412 (4)C11—C101.364 (6)
O1—C11.418 (4)C11—H11A0.9300
C6—C1i1.495 (6)C8—C131.503 (5)
C6—H6A0.9700C10—C141.512 (6)
C6—H6B0.9700C13—H13A0.9600
C4—C51.497 (6)C13—H13B0.9600
C4—H4A0.9700C13—H13C0.9600
C4—H4B0.9700C16—H16A0.9600
C5—H5A0.9700C16—H16B0.9600
C5—H5B0.9700C16—H16C0.9600
C2—C31.490 (6)C17—H17A0.9600
C2—H2A0.9700C17—H17B0.9600
C2—H2B0.9700C17—H17C0.9600
C3—H3A0.9700C15—H15A0.9600
C3—H3B0.9700C15—H15B0.9600
C1—C6i1.495 (6)C15—H15C0.9600
C1—H1A0.9700C14—H14A0.9600
C1—H1B0.9700C14—H14B0.9600
C7—C121.382 (5)C14—H14C0.9600
F1—P1—F689.5 (2)C12—C7—C8122.7 (4)
F1—P1—F391.6 (2)C12—C7—N1122.0 (4)
F6—P1—F3178.3 (2)C8—C7—N1115.4 (3)
F1—P1—F290.6 (3)C17—N1—C7116.1 (3)
F6—P1—F291.4 (2)C17—N1—C16115.4 (4)
F3—P1—F289.9 (2)C7—N1—C16114.5 (3)
F1—P1—F5179.7 (2)C17—N1—H1C102.6
F6—P1—F590.2 (2)C7—N1—H1C102.6
F3—P1—F588.7 (2)C16—N1—H1C102.6
F2—P1—F589.4 (2)C10—C9—C8122.3 (4)
F1—P1—F491.5 (2)C10—C9—H9A118.9
F6—P1—F489.15 (19)C8—C9—H9A118.9
F3—P1—F489.5 (2)C7—C12—C11116.6 (4)
F2—P1—F4177.8 (2)C7—C12—C15126.6 (4)
F5—P1—F488.5 (2)C11—C12—C15116.9 (4)
C5—O3—C6112.2 (3)C10—C11—C12123.4 (4)
C4—O2—C3112.6 (3)C10—C11—H11A118.3
C2—O1—C1112.3 (3)C12—C11—H11A118.3
O3—C6—C1i110.0 (3)C9—C8—C7117.3 (4)
O3—C6—H6A109.7C9—C8—C13119.2 (4)
C1i—C6—H6A109.7C7—C8—C13123.5 (4)
O3—C6—H6B109.7C11—C10—C9117.7 (4)
C1i—C6—H6B109.7C11—C10—C14121.5 (5)
H6A—C6—H6B108.2C9—C10—C14120.7 (5)
O2—C4—C5109.0 (3)C8—C13—H13A109.5
O2—C4—H4A109.9C8—C13—H13B109.5
C5—C4—H4A109.9H13A—C13—H13B109.5
O2—C4—H4B109.9C8—C13—H13C109.5
C5—C4—H4B109.9H13A—C13—H13C109.5
H4A—C4—H4B108.3H13B—C13—H13C109.5
O3—C5—C4110.4 (3)N1—C16—H16A109.5
O3—C5—H5A109.6N1—C16—H16B109.5
C4—C5—H5A109.6H16A—C16—H16B109.5
O3—C5—H5B109.6N1—C16—H16C109.5
C4—C5—H5B109.6H16A—C16—H16C109.5
H5A—C5—H5B108.1H16B—C16—H16C109.5
O1—C2—C3108.6 (3)N1—C17—H17A109.5
O1—C2—H2A110.0N1—C17—H17B109.5
C3—C2—H2A110.0H17A—C17—H17B109.5
O1—C2—H2B110.0N1—C17—H17C109.5
C3—C2—H2B110.0H17A—C17—H17C109.5
H2A—C2—H2B108.4H17B—C17—H17C109.5
O2—C3—C2108.7 (3)C12—C15—H15A109.5
O2—C3—H3A109.9C12—C15—H15B109.5
C2—C3—H3A109.9H15A—C15—H15B109.5
O2—C3—H3B109.9C12—C15—H15C109.5
C2—C3—H3B109.9H15A—C15—H15C109.5
H3A—C3—H3B108.3H15B—C15—H15C109.5
O1—C1—C6i109.3 (3)C10—C14—H14A109.5
O1—C1—H1A109.8C10—C14—H14B109.5
C6i—C1—H1A109.8H14A—C14—H14B109.5
O1—C1—H1B109.8C10—C14—H14C109.5
C6i—C1—H1B109.8H14A—C14—H14C109.5
H1A—C1—H1B108.3H14B—C14—H14C109.5
Symmetry code: (i) x, y+2, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1C···F40.912.383.077 (5)134
C16—H16A···O3ii0.962.523.334 (5)143
C16—H16B···O2iii0.962.513.443 (5)164
C16—H16C···O1ii0.962.573.381 (5)143
C17—H17B···F40.962.543.122 (6)119
Symmetry codes: (ii) x, y1, z; (iii) x, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1C···F40.912.383.077 (5)133.6
C16—H16A···O3i0.962.523.334 (5)143.1
C16—H16B···O2ii0.962.513.443 (5)163.6
C16—H16C···O1i0.962.573.381 (5)142.8
C17—H17B···F40.962.543.122 (6)118.9
Symmetry codes: (i) x, y1, z; (ii) x, y+1, z+1.
 

References

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