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

Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 71| Part 2| February 2015| Pages m28-m29

Crystal structure of bis­­(thio­cyanato-κS)bis­­(thio­urea-κS)mercury(II)

aDepartment of Physics, Rajeswari Vedachalam Government Arts College, Chengalpet 603 001, India, bDepartment of Physics, The New College (Autonomous), Chennai 600 014, India, and cDepartment of Physics, Loyola College (Autonomous), Chennai 600 034, India
*Correspondence e-mail: drkrr2007@gmail.com, mnizam_new@yahoo.in

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 6 January 2015; accepted 12 January 2015; online 17 January 2015)

In the title complex, [Hg(NCS)2(CH4N2S)2], the HgII atom is four-coordinated having an irregular four-coordinate geometry composed of four thione S atoms of two thio­cyanate groups and two thio­urea groups. The S—Hg—S angles are 172.02 (9)° for the trans-thio­cyanate S atoms and 90.14 (5)° for the cis-thio­urea S atoms. The mol­ecular structure is stabilized by an intra­molecular N—H⋯S hydrogen bond, which forms an S(6) ring motif. In the crystal, mol­ecules are linked by a number of N—H⋯N and N—H⋯S hydrogen bonds, forming a three-dimensional framework. The first report of the crystal structure of this compound appeared in 1966 [Korczynski (1966[Korczynski, A. (1966). Rocz. Chem. 40, 547-569.]). Rocz. Chem. 40, 547–569] with an extremely high R factor of 17.2%, and no mention of how the data were collected.

1. Related literature

For literature on thio­urea- and thio­cyanate-based metal–organic crystalline materials and their derivatives, see: Ramesh et al. (2012[Ramesh, V., Rajarajan, K., Kumar, K. S., Subashini, A. & NizamMohideen, M. (2012). Acta Cryst. E68, m335-m336.]); Shihabuddeen Syed et al. (2013[Shihabuddeen Syed, A., Rajarajan, K. & NizamMohideen, M. (2013). Acta Cryst. E69, i33.]). For the concept of hard and soft acids and bases, see: Ozutsumi et al. (1989[Ozutsumi, K., Takamuku, T., Ishiguro, S. & Ohtaki, H. (1989). Bull. Chem. Soc. Jpn, 62, 1875-1879.]); Bell et al. (2001[Bell, N. A., Branston, T. N., Clegg, W., Parker, L., Raper, E. S., Sammon, C. & Constable, C. P. (2001). Inorg. Chim. Acta, 319, 130-136.]). For the crystal structures of similar compounds, see: Nawaz et al. (2010[Nawaz, S., Sadaf, H., Fettouhi, M., Fazal, A. & Ahmad, S. (2010). Acta Cryst. E66, m952.]); Safari et al. (2009[Safari, N., Amani, V., Abedi, A., Notash, B. & Ng, S. W. (2009). Acta Cryst. E65, m372.]); Shihabuddeen Syed et al. (2013[Shihabuddeen Syed, A., Rajarajan, K. & NizamMohideen, M. (2013). Acta Cryst. E69, i33.]). For the first report of the crystal structure of the title compound, see: Korczynski (1966[Korczynski, A. (1966). Rocz. Chem. 40, 547-569.]).

[Scheme 1]

2. Experimental

2.1. Crystal data

  • [Hg(NCS)2(CH4N2S)2]

  • Mr = 468.99

  • Orthorhombic, P b c 21

  • a = 8.5359 (5) Å

  • b = 9.0337 (5) Å

  • c = 15.7575 (10) Å

  • V = 1215.07 (12) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 13.33 mm−1

  • T = 293 K

  • 0.20 × 0.20 × 0.15 mm

2.2. Data collection

  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2004[Sheldrick, G. M. (2004). SADABS. University of Göttingen, Germany.]) Tmin = 0.176, Tmax = 0.240

  • 19798 measured reflections

  • 2397 independent reflections

  • 2158 reflections with I > 2σ(I)

  • Rint = 0.058

2.3. Refinement

  • R[F2 > 2σ(F2)] = 0.029

  • wR(F2) = 0.075

  • S = 1.15

  • 2397 reflections

  • 137 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 1.44 e Å−3

  • Δρmin = −1.03 e Å−3

  • Absolute structure: Flack (1983[Flack, H. D. (1983). Acta Cryst. A39, 876-881.]), 1149 Freidel pairs.

  • Absolute structure parameter: 0.034 (12)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N3—H3B⋯S1 0.86 2.55 3.404 (7) 174
N3—H3A⋯N2i 0.86 2.37 3.103 (10) 143
N4—H4A⋯N2i 0.86 2.17 2.952 (10) 151
N4—H4B⋯N1ii 0.86 2.56 3.085 (11) 121
N5—H5A⋯N1iii 0.86 2.26 3.025 (10) 149
N5—H5A⋯S4iv 0.86 2.80 3.384 (7) 126
N5—H5B⋯N2v 0.86 2.21 3.025 (10) 158
N6—H6A⋯N1iii 0.86 2.25 3.019 (10) 149
N6—H6B⋯S2vi 0.86 2.56 3.419 (8) 172
Symmetry codes: (i) [-x+1, y-{\script{1\over 2}}, z]; (ii) [x, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]; (iii) x-1, y, z; (iv) [-x, -y+2, z-{\script{1\over 2}}]; (v) [x, -y+{\script{5\over 2}}, z-{\script{1\over 2}}]; (vi) [-x, y-{\script{1\over 2}}, z].

Data collection: APEX2 (Bruker, 2004[Bruker (2004). APEX2, SAINT and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: APEX2 and SAINT (Bruker, 2004[Bruker (2004). APEX2, SAINT and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT and XPREP (Bruker, 2004[Bruker (2004). APEX2, SAINT 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, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: WinGX (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and PLATON.

Supporting information


Synthesis and crystallization top

A mixture of thio­urea, ammonium thio­cyanate and mercury (II) chloride were dissolved in aqueous solution in the molar ratio 2:2:1 and thoroughly mixed for 1 h to obtain a homogeneous mixture. The solution was allowed to evaporate slowly at ambient temperature. Colourless block-like crystals were obtained in a week.

Refinement top

All the H atoms were positioned geometrically with N—H = 0.86 Å and constrained to ride on their parent atoms with Uiso(H) = 1.2Ueq(N).

Comment top

This work is part of a research project concerning the investigation of thiourea (N2H4CS) and thiocyanate (SCN) based metal organic crystalline materials and their derivatives (Ramesh et al., 2012; Shihabuddeen Syed et al., 2013). Transition metal thiourea and thiocyanate coordination complexes are candidate materials for device applications including their nonlinear optical properties. As ligands, both thiourea and thiocyanate are interesting due to their potential formation of metal coordination complexes as they exhibit multifunctional coordination modes due to the presence of 'S' and 'N' donor atoms. With reference to the hard and soft acids and bases) concept (Ozutsumi et al., 1989; Bell et al., 2001), the soft cations show a pronounced affinity for coordination with the softer ligands, while hard cations prefer coordination with harder ligands. Several crystallographic reports about mercury(II) complexes usually consist of discrete monomeric molecules with tetrahedral (somewhat distorted) coordination environments around mercury(II) (Nawaz et al., 2010). Herein, we report on the synthesis and crystal structure of the title complex.

The title monomeric complex is composed of two thiocyanate and two thiourea ligands coordinated to the Hg atom via the softer thione S atom (Fig. 1). The four-coordinate mercury atom adopts a severely distorted tetrahedral geometry. The S—Hg—S angles are S3-Hg1-S4 = 172.02 (9) ° for the trans thiocyanate S atoms and S1-Hg1-S2 = 90.14 (5) ° for the trans thiourea S atoms. The bond distances Hg1-S3 and Hg1-S4 are 2.390 (3) and 2.381 (3) Å, respectively, while bond distances Hg1—S1 and Hg1—S2 are 3.064818) and 3.0836 (18) Å, respectively. Bond distances and angles are in agreement with those reported for related compounds (Shihabuddeen Syed et al., 2013; Safari et al., 2009; Nawaz et al., 2010). The SCN moiety is planar [to within 0.007 (1) Å with the C-N and C-S bond lengths corresponding to the values intermediate between single and double bonds. The S2-C2-N2 and S1-C1-N1 units are nearly linear with bond angles of 178.5 (7) and 179.4 (8)°, respectively. The compound is closely related with (thiocyanato-kS)tris(thiourea-kS)mercury(II) chloride (Shihabuddeen Syed et al., 2013). The molecular structure is stabilized by intramolecular an N-H···S hydrogen bond, which forms an S(6) ring motif (Fig. 1 and Table 1).

In the crystal, molecules are connected via N-H···N hydrogen bonds, involving the thiourea NH2 H atoms and the thiocyanate N atom (Fig. 2 and Table 1). This gives rise to the formation of a three-dimensional framework which is reinforced by N-H···S hydrogen bonds (Fig. 2 and Table 1).

The first report of the crystal structure of the title compound appeared in 1966 (Korczynski, 1966) with an extremely high R factor of 17.2 %, and no mention of how the data were collected.

Related literature top

For literature on thiourea- and thiocyanate-based metal–organic crystalline materials and their derivatives, see: Ramesh et al. (2012); Shihabuddeen Syed et al. (2013). For the concept of hard and soft acids and bases, see: Ozutsumi et al. (1989); Bell et al. (2001). For the crystal structures of similar compounds, see: Nawaz et al. (2010); Safari et al. (2009); Shihabuddeen Syed et al. (2013). For the first report of the crystal structure of the title compound, see: Korczynski (1966).

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 2012) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. A view of the molecular structure of the title complex, with atom labelling. Displacement ellipsoids are drawn at the 50% probability level. The intramolecular N—H···S hydrogen bond is shown as a double dashed line (see Table 1 for details).
[Figure 2] Fig. 2. The crystal packing of the title complex, viewed along the a axis. Hydrogen bonds are shown as dashed lines (see Table 1 for details).
Bis(thiocyanato-κS)bis(thiourea-κS)mercury(II) top
Crystal data top
[Hg(NCS)2(CH4N2S)2]F(000) = 872
Mr = 468.99Dx = 2.564 Mg m3
Orthorhombic, Pbc21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2bCell parameters from 2397 reflections
a = 8.5359 (5) Åθ = 2.4–31.2°
b = 9.0337 (5) ŵ = 13.33 mm1
c = 15.7575 (10) ÅT = 293 K
V = 1215.07 (12) Å3Block, colourless
Z = 40.20 × 0.20 × 0.15 mm
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2397 independent reflections
Radiation source: fine-focus sealed tube2158 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.058
ω and ϕ scansθmax = 26.0°, θmin = 2.4°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2004)
h = 1010
Tmin = 0.176, Tmax = 0.240k = 1111
19798 measured reflectionsl = 1919
Refinement top
Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.029 w = 1/[σ2(Fo2) + (0.0237P)2 + 4.6956P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.075(Δ/σ)max = 0.001
S = 1.15Δρmax = 1.44 e Å3
2397 reflectionsΔρmin = 1.03 e Å3
137 parametersExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
1 restraintExtinction coefficient: 0.0082 (3)
Primary atom site location: structure-invariant direct methodsAbsolute structure: Flack (1983), 1149 Freidel pairs.
Secondary atom site location: difference Fourier mapAbsolute structure parameter: 0.034 (12)
Crystal data top
[Hg(NCS)2(CH4N2S)2]V = 1215.07 (12) Å3
Mr = 468.99Z = 4
Orthorhombic, Pbc21Mo Kα radiation
a = 8.5359 (5) ŵ = 13.33 mm1
b = 9.0337 (5) ÅT = 293 K
c = 15.7575 (10) Å0.20 × 0.20 × 0.15 mm
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2397 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2004)
2158 reflections with I > 2σ(I)
Tmin = 0.176, Tmax = 0.240Rint = 0.058
19798 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.029H-atom parameters constrained
wR(F2) = 0.075Δρmax = 1.44 e Å3
S = 1.15Δρmin = 1.03 e Å3
2397 reflectionsAbsolute structure: Flack (1983), 1149 Freidel pairs.
137 parametersAbsolute structure parameter: 0.034 (12)
1 restraint
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell esds are taken into account in the estimation of distances, angles and torsion angles

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
Hg10.25569 (4)0.89378 (3)0.72851 (8)0.0374 (1)
S10.4564 (2)1.1691 (2)0.69569 (13)0.0336 (6)
S20.0283 (2)1.0924 (2)0.76929 (13)0.0334 (6)
S30.2017 (3)0.8900 (3)0.57967 (14)0.0329 (7)
S40.3068 (3)0.8610 (3)0.87589 (15)0.0353 (7)
N10.6053 (9)1.0000 (9)0.5700 (5)0.041 (3)
N20.0984 (9)1.2628 (8)0.9017 (5)0.037 (3)
N30.6051 (8)0.9346 (7)0.8444 (5)0.034 (2)
N40.5630 (8)0.7508 (9)0.9391 (4)0.039 (2)
N50.0507 (8)1.0248 (7)0.5262 (4)0.031 (2)
N60.0982 (7)0.8404 (8)0.6204 (5)0.032 (2)
C10.5444 (9)1.0700 (9)0.6213 (5)0.026 (2)
C20.0478 (9)1.1927 (9)0.8463 (5)0.025 (2)
C30.5073 (8)0.8485 (9)0.8853 (5)0.026 (2)
C40.0009 (9)0.9200 (8)0.5772 (4)0.022 (2)
H3A0.704300.926700.853000.0410*
H3B0.570200.999100.809000.0410*
H4A0.662400.744000.947100.0460*
H4B0.500100.693700.966400.0460*
H5A0.149601.040500.521500.0370*
H5B0.014601.077400.497600.0370*
H6A0.197100.856300.615700.0380*
H6B0.064700.771900.653700.0380*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Hg10.0319 (2)0.0600 (2)0.0205 (2)0.0029 (1)0.0073 (2)0.0032 (3)
S10.0359 (11)0.0344 (10)0.0304 (10)0.0005 (9)0.0003 (8)0.0009 (9)
S20.0319 (11)0.0370 (10)0.0314 (11)0.0017 (9)0.0016 (9)0.0026 (9)
S30.0231 (10)0.0548 (14)0.0209 (11)0.0038 (9)0.0006 (9)0.0002 (9)
S40.0243 (11)0.0616 (14)0.0200 (11)0.0005 (10)0.0013 (9)0.0005 (10)
N10.035 (4)0.051 (5)0.038 (4)0.000 (4)0.003 (4)0.005 (4)
N20.039 (4)0.035 (4)0.037 (5)0.002 (3)0.002 (3)0.002 (3)
N30.026 (4)0.033 (4)0.044 (4)0.001 (3)0.005 (3)0.011 (3)
N40.041 (4)0.044 (4)0.031 (4)0.010 (3)0.005 (3)0.009 (3)
N50.031 (4)0.031 (4)0.030 (4)0.000 (3)0.003 (3)0.006 (3)
N60.026 (3)0.036 (4)0.033 (4)0.001 (3)0.007 (3)0.007 (3)
C10.024 (4)0.032 (4)0.022 (4)0.004 (3)0.004 (3)0.008 (3)
C20.025 (4)0.036 (4)0.015 (4)0.003 (3)0.005 (3)0.011 (3)
C30.028 (4)0.031 (4)0.019 (4)0.008 (3)0.002 (3)0.010 (3)
C40.028 (4)0.026 (4)0.012 (4)0.001 (3)0.005 (3)0.001 (3)
Geometric parameters (Å, º) top
Hg1—S13.0641 (18)N4—C31.313 (11)
Hg1—S23.0836 (18)N5—C41.318 (9)
Hg1—S32.390 (3)N6—C41.302 (10)
Hg1—S42.381 (3)N3—H3A0.8600
S1—C11.655 (8)N3—H3B0.8600
S2—C21.648 (8)N4—H4A0.8600
S3—C41.736 (8)N4—H4B0.8600
S4—C31.722 (7)N5—H5A0.8600
N1—C11.151 (11)N5—H5B0.8600
N2—C21.162 (11)N6—H6A0.8600
N3—C31.310 (10)N6—H6B0.8600
S1—Hg1—S290.14 (5)C3—N3—H3A120.00
S1—Hg1—S387.35 (8)C3—N3—H3B120.00
S1—Hg1—S499.39 (8)H3A—N3—H3B120.00
S2—Hg1—S393.51 (8)S3—C4—N5117.1 (6)
S2—Hg1—S490.75 (8)S3—C4—N6122.9 (6)
S3—Hg1—S4172.02 (9)N5—C4—N6119.9 (7)
Hg1—S1—C186.2 (3)C3—N4—H4A120.00
Hg1—S2—C299.4 (3)C3—N4—H4B120.00
Hg1—S3—C4102.1 (2)H4A—N4—H4B120.00
Hg1—S4—C3105.9 (3)C4—N5—H5A120.00
S1—C1—N1179.4 (8)C4—N5—H5B120.00
S2—C2—N2178.4 (8)H5A—N5—H5B120.00
S4—C3—N3123.5 (6)C4—N6—H6A120.00
S4—C3—N4117.4 (6)C4—N6—H6B120.00
N3—C3—N4119.1 (7)H6A—N6—H6B120.00
S2—Hg1—S1—C1145.2 (3)S2—Hg1—S3—C426.2 (3)
S3—Hg1—S1—C151.7 (3)S1—Hg1—S4—C355.8 (3)
S4—Hg1—S1—C1124.0 (3)S2—Hg1—S4—C3146.1 (3)
S1—Hg1—S2—C256.6 (3)Hg1—S3—C4—N653.0 (7)
S3—Hg1—S2—C2144.0 (3)Hg1—S3—C4—N5129.8 (5)
S4—Hg1—S2—C242.8 (3)Hg1—S4—C3—N4139.9 (6)
S1—Hg1—S3—C4116.2 (3)Hg1—S4—C3—N342.8 (8)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3B···S10.862.553.404 (7)174
N3—H3A···N2i0.862.373.103 (10)143
N4—H4A···N2i0.862.172.952 (10)151
N4—H4B···N1ii0.862.563.085 (11)121
N5—H5A···N1iii0.862.263.025 (10)149
N5—H5A···S4iv0.862.803.384 (7)126
N5—H5B···N2v0.862.213.025 (10)158
N6—H6A···N1iii0.862.253.019 (10)149
N6—H6B···S2vi0.862.563.419 (8)172
Symmetry codes: (i) x+1, y1/2, z; (ii) x, y+3/2, z+1/2; (iii) x1, y, z; (iv) x, y+2, z1/2; (v) x, y+5/2, z1/2; (vi) x, y1/2, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N3—H3B···S10.862.553.404 (7)174
N3—H3A···N2i0.862.373.103 (10)143
N4—H4A···N2i0.862.172.952 (10)151
N4—H4B···N1ii0.862.563.085 (11)121
N5—H5A···N1iii0.862.263.025 (10)149
N5—H5A···S4iv0.862.803.384 (7)126
N5—H5B···N2v0.862.213.025 (10)158
N6—H6A···N1iii0.862.253.019 (10)149
N6—H6B···S2vi0.862.563.419 (8)172
Symmetry codes: (i) x+1, y1/2, z; (ii) x, y+3/2, z+1/2; (iii) x1, y, z; (iv) x, y+2, z1/2; (v) x, y+5/2, z1/2; (vi) x, y1/2, z.
 

Acknowledgements

The authors are grateful to the SAIF, IIT, Madras, India, for the data collection. KR thanks the University Grants Commission, Government of India, for financial support granted under a Major Research Project [F. No. 41–1008/2012 (SR)].

References

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ISSN: 2056-9890
Volume 71| Part 2| February 2015| Pages m28-m29
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