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

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ISSN: 2056-9890

(E)-3-Chloro-N′-hy­dr­oxy­benzene-1-carboximidamide

aDepartment of Studies and Research in Chemistry, Tumkur University, Tumkur, Karnataka 572 103, India, bDepartment of Studies and Research in Chemistry, U.C.S, Tumkur University, Tumkur, Karnataka 572 103, India, and cDepartment of Studies and Research in Physics, U.C.S., Tumkur University, Tumkur, Karnataka 572 103, India
*Correspondence e-mail: drsreenivasa@yahoo.co.in

(Received 6 November 2012; accepted 12 November 2012; online 24 November 2012)

The title compound, C7H7ClN2O, crystallizes with two independent mol­ecules in the asymmetric unit. The compound adopts an E configuration across the C=N double bond, as the –OH group and the benzene ring are on opposite sides of the double bond while the H atom of the hy­droxy group is directed away from the –NH2 group. In the crystal, mol­ecules are linked to one another through O—H⋯N and N—H⋯O hydrogen bonds, forming chains along [010].

Related literature

For related syntheses and the biological activity of oxadiazo­les, see: Kundu et al. (2012[Kundu, M., Singh, J., Singh, B., Ghosh, T., Maiti, B. C. & Maity, T. K. (2012). Indian J. Chem. Sect. B, 51, 493-497.]); Sakamoto et al. (2007[Sakamoto, T., Cullen, M. D., Hartman, T. L., Watson, K. M., Buckheit, R. W., Pannecouque, C., DeClercq, E. & Cushman, M. (2007). J. Med. Chem. 50, 3314-3319.]); Tyrkov & Sukhenko (2004[Tyrkov, A. G. & Sukhenko, L. T. (2004). Pharm. Chem. J. 38, 30-38.]). For hydrogen-bond motifs, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • C7H7ClN2O

  • Mr = 170.60

  • Triclinic, [P \overline 1]

  • a = 5.0018 (17) Å

  • b = 10.984 (4) Å

  • c = 14.407 (6) Å

  • α = 74.000 (12)°

  • β = 89.952 (12)°

  • γ = 89.877 (11)°

  • V = 760.9 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.44 mm−1

  • T = 298 K

  • 0.24 × 0.22 × 0.20 mm

Data collection
  • Bruker SMART X2S diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2004[Sheldrick, G. M. (2004). SADABS. University of Göttingen, Germany.]) Tmin = 0.902, Tmax = 0.917

  • 14972 measured reflections

  • 2655 independent reflections

  • 2192 reflections with I > 2σ(I)

  • Rint = 0.060

Refinement
  • R[F2 > 2σ(F2)] = 0.037

  • wR(F2) = 0.109

  • S = 1.05

  • 2655 reflections

  • 218 parameters

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

  • Δρmax = 0.19 e Å−3

  • Δρmin = −0.24 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O2—H2A⋯N4i 0.82 2.09 2.811 (2) 147
N3—H3B⋯O1ii 0.92 (3) 2.32 (3) 3.006 (2) 131 (2)
O1—H1⋯N2iii 0.82 2.08 2.805 (2) 147
N1—H1B⋯O2iv 0.87 (3) 2.36 (3) 3.006 (3) 132 (3)
Symmetry codes: (i) -x+2, -y+1, -z; (ii) -x, -y+1, -z; (iii) -x-1, -y+2, -z; (iv) -x+1, -y+1, -z.

Data collection: APEX2 (Bruker, 2004[Bruker (2004). APEX, SAINT-Plus and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: APEX2 and SAINT-Plus (Bruker, 2004[Bruker (2004). APEX, SAINT-Plus and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT-Plus and XPREP (Bruker, 2004[Bruker (2004). APEX, SAINT-Plus and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); 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, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

Substituted N'-hydroxybenzamidines is a key intermediate obtained during the synthesis of pharmaceutically important 1,2,4-oxadiazole derivatives. 1,2,4-Oxadiazole derivatives are well known for their anti-HIV and anti-microbial activities (Kundu et al., 2012; Sakamoto et al., 2007; Tyrkov et al., 2004). In our studies on these types of compounds, we synthesized the title compound,C7H7ClN2O, (I) and report here its crystal structure.

The title compound, (I), crystallizes with two independent molecules (A & B) in the asymmetric unit (Fig. 1). The compound prefers an E configuration across the C—N double bond, as the OH group and the benzene ring are on opposite sides of the double bond while the hydrogen atom of the hydroxyl group is directed away from the NH2 group. In the crystal, the independent molecules (A & B) are connected to their respective crystallographically identical molecules through O1—H1···N2 and O2—H2···N4 intermolecular hydrogen bonds, each forming R22(6) dimeric pairs (Fig 2). The dimeric pairs are further connected to one another through intermolecular N1-H1N1···O2 and N3-H3N3···O1 hydrogen bonds forming a chain of ring patterns (Bernstein et al., 1995) along [010] (Fig 2).

Related literature top

For related syntheses and the biological activy of oxadiazoles, see: Kundu et al. (2012); Sakamoto et al. (2007); Tyrkov & Sukhenko (2004). For hydrogen-bond motifs, see: Bernstein et al. (1995).

Experimental top

To a solution of 3-chlorobenzonitrile (1 mmol) in ethanol was added triethyl amine (2.5 mmol) and NH2OH.HCl (3.5 mmol). The reaction mixture was stirred at room temperature for 12hrs. (The reaction was monitored by TLC). The solvent was removed and the crude product was purified by column chromatography using hexane and ethyl acetate as the eluent. Single crystals required for X-ray diffraction measurements were obtained from slow evaporation of the solution of the compound in a mixture of ethanol and dichloromethane (1:4).

Refinement top

The hydrogen atoms attached to N and O were located in difference maps and refined isotropically. The remaining H atoms were positioned geometrically and refined using a riding model, with C–H = 0.93 Å with isotropic displacement parameters set to 1.2 times of the Ueq of the parent atom.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT-Plus (Bruker, 2004); data reduction: SAINT-Plus and XPREP (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound, showing the atom-labeling scheme. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. Molecular packing of the title compound when viewed along the a axis. O—H···N and N—H···O hydrogen bonds are shown as dashed lines. Hydrogen atoms not involved in hydrogen bonding are omitted for clarity.
(E)-3-chloro-N'-hydroxybenzamidine top
Crystal data top
C7H7ClN2OF(000) = 352
Mr = 170.60Prism
Triclinic, P1Dx = 1.489 Mg m3
Hall symbol: -P 1Melting point: 386 K
a = 5.0018 (17) ÅMo Kα radiation, λ = 0.71073 Å
b = 10.984 (4) ÅCell parameters from 218 reflections
c = 14.407 (6) Åθ = 1.9–25°
α = 74.000 (12)°µ = 0.44 mm1
β = 89.952 (12)°T = 298 K
γ = 89.877 (11)°Prism, colourless
V = 760.9 (5) Å30.24 × 0.22 × 0.20 mm
Z = 4
Data collection top
Bruker SMART X2S
diffractometer
2655 independent reflections
Radiation source: fine-focus sealed tube2192 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.060
Detector resolution: 1.20 pixels mm-1θmax = 25.0°, θmin = 1.9°
phi and ω scansh = 55
Absorption correction: multi-scan
(SADABS; Sheldrick, 2004)
k = 1313
Tmin = 0.902, Tmax = 0.917l = 1717
14972 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.037H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.109 w = 1/[σ2(Fo2) + (0.0546P)2 + 0.1852P]
where P = (Fo2 + 2Fc2)/3
S = 1.05(Δ/σ)max = 0.001
2655 reflectionsΔρmax = 0.19 e Å3
218 parametersΔρmin = 0.24 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 constraintsExtinction coefficient: 0.024 (4)
Primary atom site location: structure-invariant direct methods
Crystal data top
C7H7ClN2Oγ = 89.877 (11)°
Mr = 170.60V = 760.9 (5) Å3
Triclinic, P1Z = 4
a = 5.0018 (17) ÅMo Kα radiation
b = 10.984 (4) ŵ = 0.44 mm1
c = 14.407 (6) ÅT = 298 K
α = 74.000 (12)°0.24 × 0.22 × 0.20 mm
β = 89.952 (12)°
Data collection top
Bruker SMART X2S
diffractometer
2655 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2004)
2192 reflections with I > 2σ(I)
Tmin = 0.902, Tmax = 0.917Rint = 0.060
14972 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0370 restraints
wR(F2) = 0.109H atoms treated by a mixture of independent and constrained refinement
S = 1.05Δρmax = 0.19 e Å3
2655 reflectionsΔρmin = 0.24 e Å3
218 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
H1B0.079 (5)0.805 (3)0.050 (2)0.066 (8)*
H3B0.430 (5)0.301 (3)0.047 (2)0.065 (8)*
H3A0.247 (5)0.322 (2)0.1254 (17)0.043 (6)*
H1A0.256 (5)0.823 (2)0.124 (2)0.060 (7)*
Cl10.42873 (11)0.85954 (5)0.44393 (4)0.0554 (2)
O10.3214 (3)0.87635 (13)0.00143 (11)0.0422 (4)
H10.42850.91580.03880.063*
N10.0928 (3)0.81988 (15)0.10588 (14)0.0382 (4)
N20.3071 (3)0.93253 (14)0.08000 (12)0.0356 (4)
C10.0344 (3)0.95168 (15)0.20990 (13)0.0300 (4)
C20.1471 (3)0.89050 (16)0.28068 (14)0.0345 (4)
H20.23260.81700.27630.041*
C30.1997 (4)0.93902 (17)0.35722 (14)0.0363 (4)
C40.0746 (4)1.04675 (18)0.36709 (15)0.0417 (5)
H40.11161.07830.41930.050*
C50.1068 (4)1.10622 (19)0.29740 (16)0.0456 (5)
H50.19391.17870.30300.055*
C60.1621 (4)1.06053 (17)0.21941 (15)0.0398 (5)
H60.28491.10240.17310.048*
C70.0862 (3)0.90061 (15)0.12633 (13)0.0285 (4)
Cl20.07127 (12)0.35954 (5)0.44389 (4)0.0556 (2)
O20.8210 (3)0.37629 (13)0.00125 (11)0.0420 (3)
H2A0.92560.41650.03960.063*
N30.4070 (4)0.31958 (15)0.10577 (14)0.0381 (4)
N40.8071 (3)0.43247 (15)0.08013 (12)0.0357 (4)
C80.5338 (3)0.45141 (15)0.20995 (13)0.0298 (4)
C90.3535 (4)0.39047 (16)0.28028 (14)0.0350 (4)
H90.26840.31720.27570.042*
C100.3003 (4)0.43874 (17)0.35716 (14)0.0363 (4)
C110.4257 (4)0.54666 (18)0.36691 (15)0.0422 (5)
H110.38850.57820.41920.051*
C120.6065 (4)0.60617 (19)0.29736 (16)0.0457 (5)
H120.69310.67860.30300.055*
C130.6620 (4)0.56053 (17)0.21931 (15)0.0396 (5)
H130.78450.60230.17290.048*
C140.5860 (3)0.40097 (15)0.12632 (13)0.0286 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0630 (4)0.0547 (3)0.0467 (4)0.0016 (2)0.0246 (3)0.0106 (2)
O10.0441 (8)0.0484 (8)0.0418 (8)0.0024 (6)0.0111 (6)0.0251 (7)
N10.0349 (10)0.0440 (9)0.0412 (10)0.0039 (7)0.0025 (7)0.0210 (8)
N20.0357 (9)0.0405 (8)0.0357 (9)0.0016 (6)0.0075 (7)0.0191 (7)
C10.0289 (9)0.0297 (8)0.0321 (10)0.0037 (6)0.0001 (7)0.0097 (7)
C20.0353 (10)0.0311 (9)0.0383 (11)0.0006 (7)0.0048 (8)0.0114 (8)
C30.0358 (10)0.0381 (9)0.0335 (10)0.0059 (7)0.0049 (8)0.0075 (8)
C40.0522 (12)0.0401 (10)0.0375 (11)0.0075 (8)0.0013 (9)0.0185 (9)
C50.0544 (13)0.0391 (10)0.0500 (13)0.0068 (8)0.0044 (10)0.0233 (9)
C60.0418 (11)0.0377 (10)0.0417 (11)0.0078 (8)0.0107 (8)0.0138 (8)
C70.0284 (9)0.0263 (8)0.0308 (9)0.0042 (6)0.0003 (7)0.0081 (7)
Cl20.0633 (4)0.0552 (3)0.0465 (4)0.0023 (2)0.0241 (3)0.0109 (2)
O20.0445 (8)0.0488 (8)0.0404 (8)0.0033 (6)0.0107 (6)0.0252 (7)
N30.0331 (10)0.0442 (9)0.0423 (10)0.0049 (7)0.0039 (7)0.0211 (8)
N40.0347 (9)0.0411 (8)0.0367 (9)0.0018 (6)0.0056 (7)0.0197 (7)
C80.0290 (9)0.0296 (8)0.0320 (10)0.0029 (6)0.0001 (7)0.0103 (7)
C90.0351 (10)0.0313 (9)0.0401 (11)0.0006 (7)0.0044 (8)0.0122 (8)
C100.0374 (11)0.0366 (9)0.0334 (10)0.0054 (7)0.0049 (8)0.0074 (8)
C110.0538 (13)0.0404 (10)0.0366 (11)0.0076 (8)0.0004 (9)0.0181 (9)
C120.0545 (13)0.0390 (10)0.0497 (13)0.0072 (9)0.0040 (10)0.0225 (9)
C130.0423 (11)0.0373 (10)0.0420 (12)0.0085 (8)0.0083 (8)0.0154 (8)
C140.0273 (9)0.0274 (8)0.0311 (9)0.0035 (6)0.0005 (7)0.0081 (7)
Geometric parameters (Å, º) top
Cl1—C31.7412 (19)Cl2—C101.742 (2)
O1—N21.433 (2)O2—N41.436 (2)
O1—H10.8200O2—H2A0.8200
N1—C71.347 (2)N3—C141.356 (2)
N1—H1B0.87 (3)N3—H3B0.92 (3)
N1—H1A0.86 (3)N3—H3A0.85 (2)
N2—C71.288 (2)N4—C141.288 (2)
C1—C21.391 (2)C8—C91.384 (3)
C1—C61.394 (3)C8—C131.399 (2)
C1—C71.485 (2)C8—C141.481 (2)
C2—C31.376 (3)C9—C101.379 (3)
C2—H20.9300C9—H90.9300
C3—C41.379 (3)C10—C111.383 (3)
C4—C51.377 (3)C11—C121.375 (3)
C4—H40.9300C11—H110.9300
C5—C61.380 (3)C12—C131.379 (3)
C5—H50.9300C12—H120.9300
C6—H60.9300C13—H130.9300
N2—O1—H1109.5N4—O2—H2A109.5
C7—N1—H1B116.7 (17)C14—N3—H3B116.1 (16)
C7—N1—H1A118.6 (17)C14—N3—H3A117.6 (15)
H1B—N1—H1A114 (2)H3B—N3—H3A117 (2)
C7—N2—O1109.78 (14)C14—N4—O2109.65 (14)
C2—C1—C6118.65 (17)C9—C8—C13118.93 (17)
C2—C1—C7119.67 (15)C9—C8—C14119.71 (15)
C6—C1—C7121.67 (16)C13—C8—C14121.36 (16)
C3—C2—C1119.83 (17)C10—C9—C8119.82 (16)
C3—C2—H2120.1C10—C9—H9120.1
C1—C2—H2120.1C8—C9—H9120.1
C2—C3—C4121.88 (17)C9—C10—C11121.64 (18)
C2—C3—Cl1118.24 (14)C9—C10—Cl2118.40 (14)
C4—C3—Cl1119.87 (15)C11—C10—Cl2119.96 (15)
C5—C4—C3118.08 (18)C12—C11—C10118.32 (18)
C5—C4—H4121.0C12—C11—H11120.8
C3—C4—H4121.0C10—C11—H11120.8
C4—C5—C6121.40 (18)C11—C12—C13121.28 (18)
C4—C5—H5119.3C11—C12—H12119.4
C6—C5—H5119.3C13—C12—H12119.4
C5—C6—C1120.15 (18)C12—C13—C8120.01 (18)
C5—C6—H6119.9C12—C13—H13120.0
C1—C6—H6119.9C8—C13—H13120.0
N2—C7—N1123.84 (17)N4—C14—N3123.71 (17)
N2—C7—C1117.48 (15)N4—C14—C8117.58 (15)
N1—C7—C1118.61 (16)N3—C14—C8118.62 (16)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2A···N4i0.822.092.811 (2)147
N3—H3B···O1ii0.92 (3)2.32 (3)3.006 (2)131 (2)
O1—H1···N2iii0.822.082.805 (2)147
N1—H1B···O2iv0.87 (3)2.36 (3)3.006 (3)132 (3)
Symmetry codes: (i) x+2, y+1, z; (ii) x, y+1, z; (iii) x1, y+2, z; (iv) x+1, y+1, z.

Experimental details

Crystal data
Chemical formulaC7H7ClN2O
Mr170.60
Crystal system, space groupTriclinic, P1
Temperature (K)298
a, b, c (Å)5.0018 (17), 10.984 (4), 14.407 (6)
α, β, γ (°)74.000 (12), 89.952 (12), 89.877 (11)
V3)760.9 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.44
Crystal size (mm)0.24 × 0.22 × 0.20
Data collection
DiffractometerBruker SMART X2S
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2004)
Tmin, Tmax0.902, 0.917
No. of measured, independent and
observed [I > 2σ(I)] reflections
14972, 2655, 2192
Rint0.060
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.037, 0.109, 1.05
No. of reflections2655
No. of parameters218
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.19, 0.24

Computer programs: APEX2 (Bruker, 2004), APEX2 and SAINT-Plus (Bruker, 2004), SAINT-Plus and XPREP (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 2012).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2A···N4i0.822.092.811 (2)147.2
N3—H3B···O1ii0.92 (3)2.32 (3)3.006 (2)131 (2)
O1—H1···N2iii0.822.082.805 (2)147
N1—H1B···O2iv0.87 (3)2.36 (3)3.006 (3)132 (3)
Symmetry codes: (i) x+2, y+1, z; (ii) x, y+1, z; (iii) x1, y+2, z; (iv) x+1, y+1, z.
 

Acknowledgements

The authors thank Dr S. C. Sharma, Vice Chancellor, Tumkur University, Tumkur, for his constant encouragement, and Professor T. N. Guru Row and Vijithkumar, S. S. C. U, Indian Institute of Science, Bangalore, for their help with the data collection. They also thank Dr H. C. Devarajegowda, Department of Physics, Yuvarajas College (constituent), University of Mysore, for his support.

References

First citationBernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555–1573.  CrossRef CAS Web of Science
First citationBruker (2004). APEX, SAINT-Plus and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.
First citationFarrugia, L. J. (2012). J. Appl. Cryst. 45, 849–854.  Web of Science CrossRef CAS IUCr Journals
First citationKundu, M., Singh, J., Singh, B., Ghosh, T., Maiti, B. C. & Maity, T. K. (2012). Indian J. Chem. Sect. B, 51, 493–497.
First citationSakamoto, T., Cullen, M. D., Hartman, T. L., Watson, K. M., Buckheit, R. W., Pannecouque, C., DeClercq, E. & Cushman, M. (2007). J. Med. Chem. 50, 3314–3319.  Web of Science CrossRef PubMed CAS
First citationSheldrick, G. M. (2004). SADABS. University of Göttingen, Germany.
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals
First citationTyrkov, A. G. & Sukhenko, L. T. (2004). Pharm. Chem. J. 38, 30–38.  CrossRef

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