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

Shihabuddeen Syed, A.; Rajarajan, K.; NizamMohideen, M.

doi:10.1107/S1600536813011847

inorganic compounds

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ISSN: 2056-9890

Volume 69| Part 6| June 2013| Page i33

doi:10.1107/S1600536813011847

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

A. Shihabuddeen Syed,^a K. Rajarajan ^b ^* and M. NizamMohideen ^c ^*

^aResearch and Development Center, Bharathiar University, Coimbatore 641 046, India, ^bDepartment of Physics, Rajeswari Vedachalam Government Arts College, Chengalpet 603 001, India, and ^cDepartment of Physics, The New College (Autonomous), Chennai 600 014, India
^*Correspondence e-mail: drkrr2007@gmail.com, mnizam_new@yahoo.in

(Received 5 April 2013; accepted 30 April 2013; online 4 May 2013)

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.

Related literature

For background to mercury(II) complexes with 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 ).

Experimental

Crystal data

[Hg(NCS)(CH₄N₂S)₃]Cl
M_r = 522.49
Orthorhombic, P b c a
a = 8.2175 (3) Å
b = 16.3257 (8) Å
c = 22.6793 (10) Å
V = 3042.6 (2) Å³
Z = 8
Mo Kα radiation
μ = 10.83 mm⁻¹
T = 293 K
0.30 × 0.25 × 0.20 mm

Data collection

Bruker Kappa APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2004 ) T_min = 0.140, T_max = 0.221
38987 measured reflections
5125 independent reflections
3579 reflections with I > 2σ(I)
R_int = 0.057

Refinement

R[F² > 2σ(F²)] = 0.036
wR(F²) = 0.082
S = 1.05
5125 reflections
155 parameters
H-atom parameters constrained
Δρ_max = 2.17 e Å⁻³
Δρ_min = −1.21 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯Cl1ⁱ	0.86	2.48	3.277 (4)	155
N1—H1B⋯S2	0.86	2.76	3.475 (5)	142
N2—H2A⋯Cl1ⁱ	0.86	2.55	3.335 (4)	152
N3—H3B⋯Cl1	0.86	2.61	3.320 (5)	141
N4—H4B⋯Cl1ⁱⁱ	0.86	2.51	3.370 (5)	175
N5—H5B⋯Cl1	0.86	2.54	3.363 (4)	161
N5—H5A⋯N7ⁱⁱⁱ	0.86	2.11	2.933 (7)	160
Symmetry codes: (i) x+1, y, z; (ii) $[x+{\script{1\over 2}}, y, -z+{\script{1\over 2}}]$ ; (iii) -x+2, -y, -z+1.

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 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536813011847/jj2165sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813011847/jj2165Isup2.hkl

checkCIF report

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). 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 top

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).

Experimental top

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.

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, 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 top

	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 top

Crystal data top

[Hg(NCS)(CH₄N₂S)₃]Cl	F(000) = 1968
M_r = 522.49	D_x = 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) Å³	Block, colorless
Z = 8	0.30 × 0.25 × 0.20 mm

Data collection top

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

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.036	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.082	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.0291P)² + 7.0058P] where P = (F_o² + 2F_c²)/3
5125 reflections	(Δ/σ)_max = 0.001
155 parameters	Δρ_max = 2.17 e Å⁻³
0 restraints	Δρ_min = −1.21 e Å⁻³

Crystal data top

[Hg(NCS)(CH₄N₂S)₃]Cl	V = 3042.6 (2) Å³
M_r = 522.49	Z = 8
Orthorhombic, Pbca	Mo Kα radiation
a = 8.2175 (3) Å	µ = 10.83 mm⁻¹
b = 16.3257 (8) Å	T = 293 K
c = 22.6793 (10) Å	0.30 × 0.25 × 0.20 mm

Data collection top

Bruker Kappa APEXII CCD diffractometer	5125 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2004)	3579 reflections with I > 2σ(I)
T_min = 0.140, T_max = 0.221	R_int = 0.057
38987 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.036	0 restraints
wR(F²) = 0.082	H-atom parameters constrained
S = 1.05	Δρ_max = 2.17 e Å⁻³
5125 reflections	Δρ_min = −1.21 e Å⁻³
155 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

	x	y	z	U_iso*/U_eq
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 (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
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) top

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) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···Cl1ⁱ	0.86	2.48	3.277 (4)	155
N1—H1B···S2	0.86	2.76	3.475 (5)	142
N2—H2A···Cl1ⁱ	0.86	2.55	3.335 (4)	152
N3—H3B···Cl1	0.86	2.61	3.320 (5)	141
N4—H4B···Cl1ⁱⁱ	0.86	2.51	3.370 (5)	175
N5—H5B···Cl1	0.86	2.54	3.363 (4)	161
N5—H5A···N7ⁱⁱⁱ	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.

Experimental details

Crystal data
Chemical formula	[Hg(NCS)(CH₄N₂S)₃]Cl
M_r	522.49
Crystal system, space group	Orthorhombic, Pbca
Temperature (K)	293
a, b, c (Å)	8.2175 (3), 16.3257 (8), 22.6793 (10)
V (Å³)	3042.6 (2)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	10.83
Crystal size (mm)	0.30 × 0.25 × 0.20

Data collection
Diffractometer	Bruker Kappa APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2004)
T_min, T_max	0.140, 0.221
No. of measured, independent and observed [I > 2σ(I)] reflections	38987, 5125, 3579
R_int	0.057
(sin θ/λ)_max (Å⁻¹)	0.741

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.036, 0.082, 1.05
No. of reflections	5125
No. of parameters	155
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	2.17, −1.21

Computer programs: APEX2 (Bruker, 2004), APEX2 and SAINT (Bruker, 2004), SAINT and XPREP (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2008), WinGX (Farrugia, 2012) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···Cl1ⁱ	0.86	2.48	3.277 (4)	155.2
N1—H1B···S2	0.86	2.76	3.475 (5)	141.5
N2—H2A···Cl1ⁱ	0.86	2.55	3.335 (4)	151.5
N3—H3B···Cl1	0.86	2.61	3.320 (5)	141.0
N4—H4B···Cl1ⁱⁱ	0.86	2.51	3.370 (5)	175.0
N5—H5B···Cl1	0.86	2.54	3.363 (4)	160.8
N5—H5A···N7ⁱⁱⁱ	0.86	2.11	2.933 (7)	160.0

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

Acknowledgements

The authors thank Dr Babu Vargheese, SAIF, IIT, Madras, India, for his help in collecting the X-ray intensity data. 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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