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

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ISSN: 2056-9890

Bis(cyanido-κC)bis­­(cyclo­hexyl­amine-κN)mercury(II)

aMaterials Chemistry Laboratory, Department of Chemistry, GC University, Lahore 54000, Pakistan, and bDepartment of Chemistry, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE, Scotland
*Correspondence e-mail: iuklodhi@yahoo.com

(Received 4 January 2010; accepted 8 January 2010; online 30 January 2010)

In the title compound, [Hg(CN)2(C6H13N)2], the HgII ion adopts an extremely distorted HgC2N2 tetra­hedral coordination. The crystal packing is influenced by weak N—H⋯N hydrogen bonds between the amino groups and the cyanide N atoms, resulting in chains of mol­ecules propagating in [110]. Both cyclo­hexyl­amine mol­ecules adopt chair conformations.

Related literature

For related structures, see: Ejaz et al. (2009[Ejaz, Sahin, O. & Khan, I. U. (2009). Acta Cryst. E65, m1457.]); Cingolani et al. (1987[Cingolani, A., Lorenzotti, A., Lobbia, G. G., Leonesi, D., Bonati, F. & Bovio, B. (1987). Inorg. Chim. Acta, 132, 167-176.]).

[Scheme 1]

Experimental

Crystal data
  • [Hg(CN)2(C6H13N)2]

  • Mr = 450.98

  • Triclinic, [P \overline 1]

  • a = 7.9283 (4) Å

  • b = 9.1791 (5) Å

  • c = 12.2722 (6) Å

  • α = 93.972 (3)°

  • β = 99.179 (3)°

  • γ = 97.258 (3)°

  • V = 870.95 (8) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 8.83 mm−1

  • T = 293 K

  • 0.31 × 0.23 × 0.15 mm

Data collection
  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2007[Bruker (2007). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.171, Tmax = 0.351

  • 16082 measured reflections

  • 3385 independent reflections

  • 2830 reflections with I > 2σ(I)

  • Rint = 0.041

Refinement
  • R[F2 > 2σ(F2)] = 0.061

  • wR(F2) = 0.193

  • S = 1.10

  • 3385 reflections

  • 172 parameters

  • H-atom parameters constrained

  • Δρmax = 3.17 e Å−3

  • Δρmin = −1.98 e Å−3

Table 1
Selected geometric parameters (Å, °)

Hg1—C13 2.076 (17)
Hg1—C14 2.084 (17)
Hg1—N2 2.404 (12)
Hg1—N1 2.426 (14)
C13—Hg1—C14 145.6 (7)
C13—Hg1—N2 100.1 (6)
C14—Hg1—N2 107.0 (7)
C13—Hg1—N1 101.5 (6)
C14—Hg1—N1 102.3 (7)
N2—Hg1—N1 83.4 (5)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H2⋯N3i 0.90 2.37 3.21 (2) 155
N2—H3⋯N3i 0.90 2.48 3.31 (2) 154
N2—H4⋯N4ii 0.90 2.37 3.22 (2) 157
Symmetry codes: (i) -x, -y, -z+1; (ii) -x+1, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). 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: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

As part of our ongoing studies of MX2Y2 complexes (Ejaz et al., 2009), the synthesis and structure of the title compound, (I), (Fig. 1), are now described.

The HgII atom in (I) adopts what could be described as an extremely distorted HgC2N2 tetrahedral geometry (Table 1), arising from its coordination by two cyanide anions and two cyclohexylamine ligands. As well as the gross deviations of the bond angles from nominal tetrahedral values, the Hg—C and Hg—N bond lengths are very different. Indeed, an alternative description of the structure of (I) could be to start with a nominal linear Hg(CN)2 molecule, which is then weakly coordinated by the two N-bonded ligands (Cingolani et al., 1987). The cyclohexylamine molecules in (I) adopt chair conformations.

In the crystal, the molecules interact by way of N—H···N hydrogen bonds (Table 2), leading to chains in the structure.

Surprisingly, the Cambridge Structural Database contains just one crystal structure containing an Hg(CN)2(NR)2 unit (Cingolani et al., 1987), in which the C—Hg—C bond angles in the two asymmetric molecules are 148.2 (8) and 163.1 (9)°.

Related literature top

For related structures, see: Ejaz et al. (2009); Cingolani et al. (1987).

Experimental top

Mercury(II) cyanide (0.5 g, 2.2 mmol) was dissolved in distilled water (20 ml). Cyclohexylamine (0.44 g, 4.4 mmol) was added and the mixture stirred at room temperature for 15 minutes. A white precipitate formed, which was filtered off, washed with distilled water and dried. Colourless blocks of (I) were recrystallized from methanol.

Refinement top

All the hydrogen atoms were placed in calculated positions (C—H = 0.97–0.98 Å, N—H = 0.90 Å) and refined as riding with Uiso(H) = 1.2Ueq(carrier). The highest difference peak is 1.54Å from N3 and the deepest difference hole is 0.89Å from H1A.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) showing displacement ellipsoids at the 50% probability level.
[Figure 2] Fig. 2. Unit cell packing in (I) with all C-bound hydrogen atoms omitted for clarity and hydrogen bonds indicated by dashed lines. Symmetry codes: (i) –x, –y, 1–z; (ii) 1–x, 1–y, 1–z.
Bis(cyanido-κC)bis(cyclohexylamine-κN)mercury(II) top
Crystal data top
[Hg(CN)2(C6H13N)2]V = 870.95 (8) Å3
Mr = 450.98Z = 2
Triclinic, P1F(000) = 436
Hall symbol: -P 1Dx = 1.720 Mg m3
a = 7.9283 (4) ÅMo Kα radiation, λ = 0.71073 Å
b = 9.1791 (5) ŵ = 8.83 mm1
c = 12.2722 (6) ÅT = 293 K
α = 93.972 (3)°Block, colourless
β = 99.179 (3)°0.31 × 0.23 × 0.15 mm
γ = 97.258 (3)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer
3385 independent reflections
Radiation source: fine-focus sealed tube2830 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.041
ω scansθmax = 26.0°, θmin = 2.6°
Absorption correction: multi-scan
(SADABS; Bruker, 2007)
h = 99
Tmin = 0.171, Tmax = 0.351k = 1111
16082 measured reflectionsl = 1515
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)] = 0.061Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.193H-atom parameters constrained
S = 1.10 w = 1/[σ2(Fo2) + (0.0858P)2 + 12.3401P]
where P = (Fo2 + 2Fc2)/3
3385 reflections(Δ/σ)max = 0.001
172 parametersΔρmax = 3.17 e Å3
0 restraintsΔρmin = 1.98 e Å3
Crystal data top
[Hg(CN)2(C6H13N)2]γ = 97.258 (3)°
Mr = 450.98V = 870.95 (8) Å3
Triclinic, P1Z = 2
a = 7.9283 (4) ÅMo Kα radiation
b = 9.1791 (5) ŵ = 8.83 mm1
c = 12.2722 (6) ÅT = 293 K
α = 93.972 (3)°0.31 × 0.23 × 0.15 mm
β = 99.179 (3)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer
3385 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2007)
2830 reflections with I > 2σ(I)
Tmin = 0.171, Tmax = 0.351Rint = 0.041
16082 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0610 restraints
wR(F2) = 0.193H-atom parameters constrained
S = 1.10 w = 1/[σ2(Fo2) + (0.0858P)2 + 12.3401P]
where P = (Fo2 + 2Fc2)/3
3385 reflectionsΔρmax = 3.17 e Å3
172 parametersΔρmin = 1.98 e Å3
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
Hg10.15752 (8)0.30488 (6)0.45191 (5)0.0641 (3)
C10.363 (3)0.059 (2)0.3106 (15)0.082 (5)
H1A0.45320.00490.32120.099*
C20.199 (4)0.038 (3)0.272 (2)0.132 (11)
H2A0.10360.01840.26160.159*
H2B0.17840.10960.32470.159*
C30.221 (5)0.119 (3)0.158 (2)0.155 (14)
H3A0.31800.17360.16940.187*
H3B0.11800.18840.12890.187*
C40.249 (4)0.013 (4)0.077 (2)0.148 (12)
H4A0.15560.04620.06700.177*
H4B0.25380.06440.00570.177*
C50.420 (6)0.083 (4)0.123 (3)0.176 (17)
H5A0.44610.15380.07090.211*
H5B0.51160.02150.13180.211*
C60.414 (4)0.166 (3)0.236 (2)0.125 (9)
H6A0.52680.21980.26720.150*
H6B0.33200.23580.22690.150*
N10.3599 (18)0.1352 (17)0.4211 (11)0.074 (4)
H10.46620.18520.44460.089*
H20.34570.06430.46730.089*
C70.197 (3)0.355 (2)0.7345 (14)0.085 (5)
H70.07340.32080.72710.102*
C80.220 (3)0.509 (2)0.7259 (16)0.096 (6)
H8A0.16530.52750.65280.115*
H8B0.34250.54310.73310.115*
C90.145 (5)0.598 (3)0.814 (2)0.150 (13)
H9A0.16650.70250.80560.180*
H9B0.02150.56860.80610.180*
C100.232 (5)0.566 (3)0.925 (2)0.134 (10)
H10A0.35230.60920.93500.160*
H10B0.17980.61420.98120.160*
C110.222 (5)0.407 (3)0.940 (2)0.137 (11)
H11A0.10410.36730.94330.164*
H11B0.29310.39461.01010.164*
C120.284 (3)0.324 (2)0.8463 (15)0.097 (6)
H12A0.40760.35120.85230.117*
H12B0.26190.21910.85340.117*
N20.2619 (18)0.2820 (14)0.6440 (9)0.068 (3)
H30.24710.18490.65290.082*
H40.37660.31110.65520.082*
C130.073 (2)0.1629 (18)0.4292 (15)0.067 (4)
N30.196 (2)0.0797 (19)0.4154 (15)0.090 (4)
C140.282 (2)0.504 (2)0.4133 (18)0.089 (6)
N40.352 (3)0.610 (2)0.395 (2)0.116 (6)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Hg10.0633 (4)0.0592 (4)0.0654 (4)0.0021 (2)0.0064 (3)0.0050 (3)
C10.080 (11)0.096 (13)0.067 (10)0.004 (10)0.014 (9)0.006 (9)
C20.16 (2)0.111 (17)0.118 (19)0.051 (16)0.064 (18)0.043 (15)
C30.24 (4)0.117 (19)0.090 (17)0.06 (2)0.06 (2)0.061 (16)
C40.15 (2)0.22 (4)0.058 (13)0.00 (2)0.005 (14)0.031 (18)
C50.26 (5)0.16 (3)0.11 (2)0.05 (3)0.11 (3)0.016 (19)
C60.16 (2)0.118 (19)0.086 (15)0.035 (17)0.026 (15)0.003 (13)
N10.069 (8)0.088 (9)0.060 (8)0.005 (7)0.009 (6)0.014 (7)
C70.111 (15)0.088 (12)0.052 (9)0.017 (11)0.007 (9)0.010 (8)
C80.121 (16)0.095 (14)0.065 (11)0.037 (12)0.005 (10)0.023 (10)
C90.21 (3)0.13 (2)0.11 (2)0.09 (2)0.02 (2)0.026 (17)
C100.20 (3)0.12 (2)0.083 (16)0.03 (2)0.025 (18)0.032 (14)
C110.20 (3)0.13 (2)0.074 (14)0.01 (2)0.041 (17)0.019 (14)
C120.142 (19)0.086 (13)0.061 (11)0.013 (13)0.013 (11)0.003 (9)
N20.086 (9)0.064 (7)0.045 (6)0.024 (6)0.008 (6)0.005 (5)
C130.056 (9)0.064 (9)0.083 (11)0.010 (7)0.015 (8)0.018 (8)
N30.072 (10)0.090 (11)0.103 (12)0.013 (9)0.001 (8)0.012 (9)
C140.067 (10)0.084 (12)0.114 (15)0.004 (9)0.007 (10)0.048 (11)
N40.090 (12)0.100 (13)0.153 (19)0.005 (10)0.013 (12)0.034 (13)
Geometric parameters (Å, º) top
Hg1—C132.076 (17)N1—H20.9000
Hg1—C142.084 (17)C7—C81.41 (3)
Hg1—N22.404 (12)C7—N21.45 (2)
Hg1—N12.426 (14)C7—C121.50 (3)
C1—C61.45 (3)C7—H70.9800
C1—C21.47 (3)C8—C91.55 (3)
C1—N11.49 (2)C8—H8A0.9700
C1—H1A0.9800C8—H8B0.9700
C2—C31.58 (3)C9—C101.48 (4)
C2—H2A0.9700C9—H9A0.9700
C2—H2B0.9700C9—H9B0.9700
C3—C41.45 (4)C10—C111.48 (4)
C3—H3A0.9700C10—H10A0.9700
C3—H3B0.9700C10—H10B0.9700
C4—C51.53 (4)C11—C121.52 (3)
C4—H4A0.9700C11—H11A0.9700
C4—H4B0.9700C11—H11B0.9700
C5—C61.55 (3)C12—H12A0.9700
C5—H5A0.9700C12—H12B0.9700
C5—H5B0.9700N2—H30.9000
C6—H6A0.9700N2—H40.9000
C6—H6B0.9700C13—N31.14 (2)
N1—H10.9000C14—N41.12 (2)
C13—Hg1—C14145.6 (7)Hg1—N1—H2106.6
C13—Hg1—N2100.1 (6)H1—N1—H2106.5
C14—Hg1—N2107.0 (7)C8—C7—N2109.0 (17)
C13—Hg1—N1101.5 (6)C8—C7—C12109.4 (16)
C14—Hg1—N1102.3 (7)N2—C7—C12113.0 (17)
N2—Hg1—N183.4 (5)C8—C7—H7108.4
C6—C1—C2116 (2)N2—C7—H7108.4
C6—C1—N1109.7 (17)C12—C7—H7108.4
C2—C1—N1109.9 (16)C7—C8—C9114 (2)
C6—C1—H1A106.8C7—C8—H8A108.8
C2—C1—H1A106.8C9—C8—H8A108.8
N1—C1—H1A106.8C7—C8—H8B108.8
C1—C2—C3105 (2)C9—C8—H8B108.8
C1—C2—H2A110.7H8A—C8—H8B107.7
C3—C2—H2A110.7C10—C9—C8107 (2)
C1—C2—H2B110.7C10—C9—H9A110.3
C3—C2—H2B110.7C8—C9—H9A110.3
H2A—C2—H2B108.8C10—C9—H9B110.3
C4—C3—C2111 (2)C8—C9—H9B110.3
C4—C3—H3A109.4H9A—C9—H9B108.5
C2—C3—H3A109.4C11—C10—C9114 (2)
C4—C3—H3B109.4C11—C10—H10A108.8
C2—C3—H3B109.4C9—C10—H10A108.8
H3A—C3—H3B108.0C11—C10—H10B108.8
C3—C4—C5106 (3)C9—C10—H10B108.8
C3—C4—H4A110.5H10A—C10—H10B107.7
C5—C4—H4A110.5C10—C11—C12111 (2)
C3—C4—H4B110.5C10—C11—H11A109.4
C5—C4—H4B110.5C12—C11—H11A109.4
H4A—C4—H4B108.7C10—C11—H11B109.4
C4—C5—C6111 (3)C12—C11—H11B109.4
C4—C5—H5A109.4H11A—C11—H11B108.0
C6—C5—H5A109.4C7—C12—C11113 (2)
C4—C5—H5B109.4C7—C12—H12A109.1
C6—C5—H5B109.4C11—C12—H12A109.1
H5A—C5—H5B108.0C7—C12—H12B109.1
C1—C6—C5109 (2)C11—C12—H12B109.1
C1—C6—H6A110.0H12A—C12—H12B107.8
C5—C6—H6A110.0C7—N2—Hg1123.3 (12)
C1—C6—H6B110.0C7—N2—H3106.5
C5—C6—H6B110.0Hg1—N2—H3106.5
H6A—C6—H6B108.4C7—N2—H4106.5
C1—N1—Hg1123.1 (12)Hg1—N2—H4106.5
C1—N1—H1106.6H3—N2—H4106.5
Hg1—N1—H1106.6N3—C13—Hg1177.0 (15)
C1—N1—H2106.6N4—C14—Hg1178.2 (19)
C6—C1—C2—C357 (3)N2—C7—C8—C9176 (2)
N1—C1—C2—C3177 (2)C12—C7—C8—C960 (3)
C1—C2—C3—C462 (4)C7—C8—C9—C1059 (3)
C2—C3—C4—C564 (4)C8—C9—C10—C1153 (4)
C3—C4—C5—C660 (4)C9—C10—C11—C1252 (4)
C2—C1—C6—C556 (4)C8—C7—C12—C1155 (3)
N1—C1—C6—C5179 (3)N2—C7—C12—C11177 (2)
C4—C5—C6—C155 (4)C10—C11—C12—C751 (3)
C6—C1—N1—Hg166 (2)C8—C7—N2—Hg158 (2)
C2—C1—N1—Hg163 (2)C12—C7—N2—Hg1179.6 (13)
C13—Hg1—N1—C169.3 (14)C13—Hg1—N2—C777.6 (14)
C14—Hg1—N1—C185.7 (14)C14—Hg1—N2—C780.9 (14)
N2—Hg1—N1—C1168.3 (14)N1—Hg1—N2—C7178.2 (14)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H2···N3i0.902.373.21 (2)155
N2—H3···N3i0.902.483.31 (2)154
N2—H4···N4ii0.902.373.22 (2)157
Symmetry codes: (i) x, y, z+1; (ii) x+1, y+1, z+1.

Experimental details

Crystal data
Chemical formula[Hg(CN)2(C6H13N)2]
Mr450.98
Crystal system, space groupTriclinic, P1
Temperature (K)293
a, b, c (Å)7.9283 (4), 9.1791 (5), 12.2722 (6)
α, β, γ (°)93.972 (3), 99.179 (3), 97.258 (3)
V3)870.95 (8)
Z2
Radiation typeMo Kα
µ (mm1)8.83
Crystal size (mm)0.31 × 0.23 × 0.15
Data collection
DiffractometerBruker Kappa APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2007)
Tmin, Tmax0.171, 0.351
No. of measured, independent and
observed [I > 2σ(I)] reflections
16082, 3385, 2830
Rint0.041
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.061, 0.193, 1.10
No. of reflections3385
No. of parameters172
H-atom treatmentH-atom parameters constrained
w = 1/[σ2(Fo2) + (0.0858P)2 + 12.3401P]
where P = (Fo2 + 2Fc2)/3
Δρmax, Δρmin (e Å3)3.17, 1.98

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997).

Selected geometric parameters (Å, º) top
Hg1—C132.076 (17)Hg1—N22.404 (12)
Hg1—C142.084 (17)Hg1—N12.426 (14)
C13—Hg1—C14145.6 (7)C13—Hg1—N1101.5 (6)
C13—Hg1—N2100.1 (6)C14—Hg1—N1102.3 (7)
C14—Hg1—N2107.0 (7)N2—Hg1—N183.4 (5)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H2···N3i0.902.373.21 (2)155
N2—H3···N3i0.902.483.31 (2)154
N2—H4···N4ii0.902.373.22 (2)157
Symmetry codes: (i) x, y, z+1; (ii) x+1, y+1, z+1.
 

Acknowledgements

IUK thanks the Higher Education Commission of Pakistan for its financial support under the project `Strengthening of Materials Chemistry Laboratory at GCUL'.

References

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