(Thio­cyanato-κS)­tris­(thio­urea-κS)mercury(II) chloride

In the title salt, [Hg(NCS)(CH₄N₂S)₃]Cl, the Hg²⁺ ion is coordinated in a severely distorted tetra­hedral manner by three thio­urea groups and one thio­cyanate anion through their S atoms. The S—Hg—S angles vary widely from 87.39 (5) to 128.02 (4)°. Weak intra­molecular N—H...S hydrogen bonds are observed, which form S(6) ring motifs. In the crystal, the ions are linked by N—H...N and weak N—H...Cl inter­actions, generating a three-dimensional network.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](N-C) = 0.007 Å
• R factor = 0.036
• wR factor = 0.082
• Data-to-parameter ratio = 33.1

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C2
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C3
PLAT905_ALERT_3_C Negative K value in the Analysis of Variance ...     -0.374
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          1
PLAT973_ALERT_2_C Large Calcd. Positive Residual Density on    Hg1       1.24 eA-3
PLAT975_ALERT_2_C Positive Residual Density at 0.86A from N4     .       0.48 eA-3

Alert level G
FORMU01_ALERT_1_G  There is a discrepancy between the atom counts in the
            _chemical_formula_sum and _chemical_formula_moiety. This is
            usually due to the moiety formula being in the wrong format.
            Atom count from _chemical_formula_sum:   C4 H12 Cl1 Hg1 N7 S4
            Atom count from _chemical_formula_moiety:C4 H12 Cl2 Hg1 N7 S4
PLAT005_ALERT_5_G No _iucr_refine_instructions_details  in the CIF          ?
PLAT007_ALERT_5_G Note: Number of Unrefined D-H Atoms ............         12
PLAT042_ALERT_1_G Calc. and Reported MoietyFormula Strings  Differ          ?
PLAT083_ALERT_2_G SHELXL Second Parameter in WGHT Unusually Large.       7.01
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported   _diffrn_ambient_temperature        293 K
PLAT232_ALERT_2_G Hirshfeld Test Diff (M-X)  Hg1    --  S1      ..       14.8 su
PLAT232_ALERT_2_G Hirshfeld Test Diff (M-X)  Hg1    --  S2      ..       30.3 su
PLAT764_ALERT_4_G Overcomplete CIF Bond List Detected (Rep/Expd) .       1.13 Ratio
PLAT912_ALERT_4_G Missing # of FCF Reflections Above STh/L=  0.600         55

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   6 ALERT level C = Check. Ensure it is not caused by an omission or oversight
  11 ALERT level G = General information/check it is not something unexpected

   4 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   7 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion
   2 ALERT type 5 Informative message, check

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S1. Comment

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). 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 metalcoordination 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 (Ozutsmi et al., 1989; Bell et al., 2001), thesoft 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). Here, we report the synthesis and structure of the title salt, [(SC(2NH₂))₃(SCN^-)Hg(²⁺]⁺ . Cl^-,(I).

In (I), the Hg²⁺ ion is coordinated to three softer S atoms of thiourea and one softer S atom of a thiocyanate anion in addition to the isolated chlorine ion (Fig. 1). Intramolecular N—H···S hydrogen bonds are observed which form S(6) ring motifs (Bernstein et al., 1995). Bond distances and angles are in agreement with those reported for related compounds (Safari et al., 2009; Nawaz et al., 2010). The S—Hg—S angles vary widely from 87.39 (5)° to 128.02 (4)°, indicative of a distorted tetrahedral arrangement. 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—C4—N7 unit is nearly linear with a bond angle of 177.9 (6)°. In the crystal, the ions are stabilized by weak N—H···Cl, and N—H···N intermolecular interactions (Table.1) which form a three-dimensional network (Fig. 2).

Related literature

For background to mercury(II) complexes of thiourea and thiocyanate ligands, see: Nawaz et al. (2010). For hard and soft acids and bases, see: Ozutsmi et al. (1989); Bell et al. (2001). For related structures, see: Safari et al. (2009); Nawaz et al. (2010); Ramesh et al. (2012). For graph-set notation, see: Bernstein et al. (1995).

S2. Experimental

A mixture of thiourea, ammonium thiocyanate and mercury (II) choloride were dissolved in aqueous solution in the molar ratio 3:1:1 and thoroughly mixed for an hour to obtain a homogenous mixture. The solution was allowed to evaporate slowly at ambient temperature. Colourless single crystals suitable for single-crystal XRD were obtained in 12 days.

S3. Refinement

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

Computing details

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, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2008); software used to prepare material for publication: WinGX (Farrugia, 2012) and PLATON (Spek, 2009).

Figures

	Fig. 1. View of the title compound showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 40% probability level. H atoms are presented as a small spheres of arbitrary radius.
	Fig. 2. Packing diagram of (I) viewed along the a axis. Intramolecular N—H···S hydrogen bonds and weak N—H···Cl, and N—H···N intermolecular interactions are shown as dashed lines.

(Thiocyanato-κS)tris(thiourea-κS)mercury(II) chloride

Crystal data

[Hg(NCS)(CH4N2S)3]Cl	F(000) = 1968
Mr = 522.49	Dx = 2.281 Mg m^−3
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 5125 reflections
a = 8.2175 (3) Å	θ = 2.4–31.2°
b = 16.3257 (8) Å	µ = 10.83 mm^−1
c = 22.6793 (10) Å	T = 293 K
V = 3042.6 (2) Å^3	Block, colorless
Z = 8	0.30 × 0.25 × 0.20 mm

Data collection

Bruker Kappa APEXII CCD diffractometer	5125 independent reflections
Radiation source: fine-focus sealed tube	3579 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.057
ω and ϕ scans	θmax = 31.8°, θmin = 2.5°
Absorption correction: multi-scan (SADABS; Sheldrick, 2004)	h = −12→6
Tmin = 0.140, Tmax = 0.221	k = −23→24
38987 measured reflections	l = −32→33

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.036	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.082	H-atom parameters constrained
S = 1.05	w = 1/[σ^2(Fo^2) + (0.0291P)^2 + 7.0058P] where P = (Fo^2 + 2Fc^2)/3
5125 reflections	(Δ/σ)max = 0.001
155 parameters	Δρmax = 2.17 e Å^−3
0 restraints	Δρmin = −1.21 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
C1	1.2410 (5)	0.1993 (3)	0.42350 (17)	0.0280 (8)
C2	1.0389 (5)	0.3016 (3)	0.2771 (2)	0.0321 (9)
C3	0.7067 (6)	0.0234 (3)	0.43089 (19)	0.0333 (9)
C4	1.2429 (7)	−0.0184 (3)	0.3691 (2)	0.0498 (13)
N1	1.3113 (5)	0.1934 (3)	0.37245 (16)	0.0488 (12)
H1A	1.4063	0.2142	0.3671	0.059*
H1B	1.2628	0.1687	0.3439	0.059*
N2	1.3169 (5)	0.2370 (3)	0.46633 (17)	0.0445 (10)
H2A	1.4119	0.2575	0.4604	0.053*
H2B	1.2718	0.2414	0.5004	0.053*
N3	1.0072 (6)	0.3302 (3)	0.32922 (19)	0.0511 (11)
H3A	1.0352	0.3794	0.3383	0.061*
H3B	0.9582	0.2999	0.3547	0.061*
N4	1.1131 (6)	0.3476 (3)	0.2386 (2)	0.0541 (12)
H4A	1.1409	0.3967	0.2477	0.065*
H4B	1.1342	0.3287	0.2040	0.065*
N5	0.6681 (6)	0.0872 (3)	0.46201 (18)	0.0496 (11)
H5A	0.6676	0.0844	0.4999	0.060*
H5B	0.6430	0.1324	0.4448	0.060*
N6	0.7440 (8)	−0.0438 (3)	0.4576 (2)	0.0667 (15)
H6A	0.7430	−0.0458	0.4955	0.080*
H6B	0.7698	−0.0865	0.4375	0.080*
N7	1.2853 (8)	−0.0407 (4)	0.4142 (2)	0.0779 (18)
Hg1	0.92567 (2)	0.123362 (12)	0.340864 (7)	0.03933 (7)
S1	1.05319 (12)	0.15817 (7)	0.43857 (4)	0.0313 (2)
S2	1.18864 (19)	0.01386 (9)	0.30317 (6)	0.0529 (4)
S3	0.70350 (17)	0.02592 (8)	0.35487 (5)	0.0430 (3)
S4	0.98486 (18)	0.20568 (7)	0.25448 (5)	0.0411 (3)
Cl1	0.66976 (13)	0.27345 (7)	0.39858 (4)	0.0323 (2)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.025 (2)	0.034 (2)	0.0245 (18)	0.0005 (16)	−0.0007 (15)	0.0005 (16)
C2	0.029 (2)	0.028 (2)	0.040 (2)	−0.0008 (16)	0.0019 (17)	−0.0016 (17)
C3	0.039 (3)	0.029 (2)	0.031 (2)	−0.0060 (18)	0.0015 (18)	0.0054 (17)
C4	0.060 (3)	0.044 (3)	0.046 (3)	0.022 (3)	0.006 (2)	−0.005 (2)
N1	0.032 (2)	0.090 (3)	0.0248 (18)	−0.021 (2)	0.0068 (15)	−0.010 (2)
N2	0.036 (2)	0.066 (3)	0.0310 (19)	−0.019 (2)	0.0034 (16)	−0.0137 (19)
N3	0.061 (3)	0.037 (2)	0.055 (3)	−0.013 (2)	0.019 (2)	−0.0159 (19)
N4	0.076 (3)	0.030 (2)	0.057 (3)	−0.015 (2)	0.024 (2)	−0.0046 (19)
N5	0.078 (3)	0.034 (2)	0.037 (2)	0.007 (2)	0.002 (2)	0.0028 (18)
N6	0.123 (5)	0.037 (3)	0.040 (2)	0.026 (3)	0.002 (3)	0.008 (2)
N7	0.110 (5)	0.079 (4)	0.044 (3)	0.043 (4)	0.005 (3)	0.008 (3)
Hg1	0.04559 (12)	0.04260 (11)	0.02981 (9)	−0.01684 (8)	−0.00241 (7)	0.00517 (7)
S1	0.0253 (5)	0.0458 (6)	0.0226 (4)	−0.0040 (4)	0.0020 (4)	−0.0053 (4)
S2	0.0672 (10)	0.0556 (8)	0.0358 (6)	0.0222 (7)	−0.0004 (6)	−0.0097 (6)
S3	0.0545 (8)	0.0436 (7)	0.0310 (5)	−0.0259 (6)	−0.0047 (5)	0.0018 (5)
S4	0.0683 (8)	0.0323 (6)	0.0227 (5)	−0.0161 (6)	−0.0053 (5)	0.0020 (4)
Cl1	0.0305 (5)	0.0362 (5)	0.0301 (5)	−0.0054 (4)	−0.0013 (4)	0.0004 (4)

Geometric parameters (Å, º)

C1—N1	1.297 (5)	N2—H2B	0.8600
C1—N2	1.309 (5)	N3—H3A	0.8600
C1—S1	1.717 (4)	N3—H3B	0.8600
C2—N3	1.297 (6)	N4—H4A	0.8600
C2—N4	1.302 (6)	N4—H4B	0.8600
C2—S4	1.707 (4)	N5—H5A	0.8600
C3—N6	1.290 (6)	N5—H5B	0.8600
C3—N5	1.298 (6)	N6—H6A	0.8600
C3—S3	1.725 (4)	N6—H6B	0.8600
C4—N7	1.141 (7)	Hg1—S4	2.4250 (11)
C4—S2	1.647 (6)	Hg1—S3	2.4422 (12)
C4—S2	1.647 (6)	Hg1—S1	2.5162 (10)
N1—H1A	0.8600	Hg1—S2	2.9320 (14)
N1—H1B	0.8600	Hg1—S2	2.9320 (14)
N2—H2A	0.8600
N1—C1—N2	119.0 (4)	C2—N4—H4B	120.0
N1—C1—S1	123.3 (3)	H4A—N4—H4B	120.0
N2—C1—S1	117.7 (3)	C3—N5—H5A	120.0
N3—C2—N4	119.9 (4)	C3—N5—H5B	120.0
N3—C2—S4	123.4 (4)	H5A—N5—H5B	120.0
N4—C2—S4	116.7 (4)	C3—N6—H6A	120.0
N6—C3—N5	119.1 (4)	C3—N6—H6B	120.0
N6—C3—S3	119.6 (4)	H6A—N6—H6B	120.0
N5—C3—S3	121.4 (4)	S4—Hg1—S3	128.02 (4)
N7—C4—S2	177.9 (6)	S4—Hg1—S1	120.18 (4)
N7—C4—S2	177.9 (6)	S3—Hg1—S1	110.11 (4)
C1—N1—H1A	120.0	S4—Hg1—S2	87.39 (5)
C1—N1—H1B	120.0	S3—Hg1—S2	101.05 (5)
H1A—N1—H1B	120.0	S1—Hg1—S2	95.02 (4)
C1—N2—H2A	120.0	S4—Hg1—S2	87.39 (5)
C1—N2—H2B	120.0	S3—Hg1—S2	101.05 (5)
H2A—N2—H2B	120.0	S1—Hg1—S2	95.02 (4)
C2—N3—H3A	120.0	C1—S1—Hg1	106.69 (14)
C2—N3—H3B	120.0	C4—S2—Hg1	97.45 (18)
H3A—N3—H3B	120.0	C3—S3—Hg1	97.71 (15)
C2—N4—H4A	120.0	C2—S4—Hg1	108.55 (16)
N1—C1—S1—Hg1	−14.6 (4)	S2—Hg1—S2—C4	0 (9)
N2—C1—S1—Hg1	166.6 (3)	N6—C3—S3—Hg1	−115.5 (4)
S4—Hg1—S1—C1	−32.03 (16)	N5—C3—S3—Hg1	66.4 (4)
S3—Hg1—S1—C1	161.59 (16)	S4—Hg1—S3—C3	−160.34 (16)
S2—Hg1—S1—C1	57.87 (16)	S1—Hg1—S3—C3	4.69 (17)
S2—Hg1—S1—C1	57.87 (16)	S2—Hg1—S3—C3	104.27 (17)
S2—C4—S2—Hg1	0 (100)	S2—Hg1—S3—C3	104.27 (17)
S4—Hg1—S2—S2	0.00 (8)	N3—C2—S4—Hg1	−17.9 (5)
S3—Hg1—S2—S2	0.00 (8)	N4—C2—S4—Hg1	163.4 (4)
S1—Hg1—S2—S2	0.00 (8)	S3—Hg1—S4—C2	138.25 (16)
S4—Hg1—S2—C4	150.5 (2)	S1—Hg1—S4—C2	−25.45 (17)
S3—Hg1—S2—C4	−81.2 (2)	S2—Hg1—S4—C2	−119.74 (17)
S1—Hg1—S2—C4	30.5 (2)	S2—Hg1—S4—C2	−119.74 (17)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···Cl1^i	0.86	2.48	3.277 (4)	155
N1—H1B···S2	0.86	2.76	3.475 (5)	142
N2—H2A···Cl1^i	0.86	2.55	3.335 (4)	152
N3—H3B···Cl1	0.86	2.61	3.320 (5)	141
N4—H4B···Cl1^ii	0.86	2.51	3.370 (5)	175
N5—H5B···Cl1	0.86	2.54	3.363 (4)	161
N5—H5A···N7^iii	0.86	2.11	2.933 (7)	160

Symmetry codes: (i) x+1, y, z; (ii) x+1/2, y, −z+1/2; (iii) −x+2, −y, −z+1.