Dichloridobis(1,10-phenanthroline-5,6-dione-κ2N,N′)mercury(II)

Figueiras, C.A.L.; Bomfim, J.A.S.; Howie, R.A.; Tiekink, E.R.T.; Wardell, J.L.

doi:10.1107/S1600536809049289

metal-organic compounds

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ISSN: 2056-9890

Volume 65| Part 12| December 2009| Page m1645

doi:10.1107/S1600536809049289

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Dichloridobis(1,10-phenanthroline-5,6-dione-κ²N,N′)mercury(II)

Carlos A. L. Figueiras,^a João A. S. Bomfim,^a R. Alan Howie,^b Edward R. T. Tiekink ^c ^* and James L. Wardell ^d ‡

^aDepartamento de Química Inorgânica, Instituto de Química, Universidade Federal do Rio de Janeiro, CP 68563, 21941-909 Rio de Janeiro, RJ, Brazil, ^bDepartment of Chemistry, University of Aberdeen, Old Aberdeen, AB15 5NY, Scotland, ^cDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia, and ^dDepartamento de Quimica, ICEx, Universidade Federal de Minas Gerais, 31270-901 Belo Horizonte, MG, Brazil
^*Correspondence e-mail: edward.tiekink@gmail.com

(Received 10 November 2009; accepted 18 November 2009; online 21 November 2009)

In the title compound, [HgCl₂(C₁₂H₆N₂O₂)₂], the Hg^II atom is located on a twofold rotation axis and exists within a distorted octahedral geometry defined by a cis-Cl₂N₄ donor set. Molecules are connected into layers in the ac plane via extensive C—H⋯Cl contacts as each Cl atom forms two such interactions. Contacts between the layers are of the type C=O⋯π [O⋯centroid distance = 3.110 (8) Å].

Related literature

For related main-group compounds of 1,10-phenanthroline-5,6-dione, see: de Alencastro et al. (2005 ). For the ligand synthesis, see: Yamada et al. (1992 ). For a related structure, see: Ramezanipour et al. (2005 ).

Experimental

Crystal data

[HgCl₂(C₁₂H₆N₂O₂)₂]
M_r = 691.87
Orthorhombic, F d d 2
a = 8.2261 (2) Å
b = 42.6761 (11) Å
c = 12.6108 (3) Å
V = 4427.12 (19) Å³
Z = 8
Mo Kα radiation
μ = 7.24 mm⁻¹
T = 120 K
0.20 × 0.10 × 0.06 mm

Data collection

Nonius KappaCCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.204, T_max = 0.651
10751 measured reflections
2487 independent reflections
2239 reflections with I > 2σ(I)
R_int = 0.075

Refinement

R[F² > 2σ(F²)] = 0.037
wR(F²) = 0.094
S = 1.05
2487 reflections
159 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 2.27 e Å⁻³
Δρ_min = −0.68 e Å⁻³
Absolute structure: Flack (1983 ), 1163 Friedel pairs
Flack parameter: −0.012 (13)

Table 1
Selected bond lengths (Å)

Hg—N1	2.439 (7)
Hg—N2	2.512 (6)
Hg—Cl1	2.5270 (19)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2⋯Cl1ⁱ	0.95	2.69	3.578 (8)	156
C9—H9⋯Cl1ⁱⁱ	0.95	2.78	3.701 (8)	164
Symmetry codes: (i) x-1, y, z; (ii) $[x+{\script{1\over 2}}, y, z-{\script{1\over 2}}]$ .

Data collection: COLLECT (Hooft, 1998 ); cell refinement: DENZO (Otwinowski & Minor, 1997 ) and COLLECT; data reduction: DENZO and COLLECT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999 ); software used to prepare material for publication: publCIF (Westrip, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809049289/hy2254sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809049289/hy2254Isup2.hkl

checkCIF report

Comment top

In continuation of the previous studies of coordination compounds of 1,10-phenanthroline-5,6-dione (pdon) ligand (de Alencastro et al., 2005), the title compound, HgCl₂(pdon)₂, was investigated. The reaction of HgCl₂ with pdon (1:1 mol ratio) led to the isolation of a pure 1:1 complex, HgCl₂(pdon). However, as the product was unsuitable for X-ray crystallography, a further recrystallization from MeNO₂ solution was attempted, which led to the isolation of the title compound, a 1:2 complex. Of interest was that the 1:1 HgI₂(pdon) complex, prepared similarly to the chloride analogue, was recovered on recrystallization from MeNO₂. Unfortunately this set of crystals also proved unsuitable for X-ray crystallography.

In the title compound, the Hg^II atom lies on a crystallographic twofold axis and exists within a cis-Cl₂N₄ donor set defined by two Cl atoms and four N atoms derived from two chelating pdon ligands (Fig. 1). There is a small disparity in the magnitude of the Hg—N bond distances, with Hg—N1 of 2.439 (7) Å being shorter than Hg—N2 of 2.512 (6) Å. Distortions from an ideal octahedral geometry are related in part to the acute chelate angle of 66.9 (2)°. The pdon ligand is essentially planar with a RMS of 0.226 Å for the N and C atoms, with O1 and O2 atoms lying, respectively, -0.079 (12) and 0.071 (13) Å out of the least-squares plane. The dihedral angle formed between the symmetry related 1,10-phenanthroline planes is 87.13 (11)°. The structural features described herein for the title compound resemble those found for HgCl₂(1,10-phenanthroline)₂ (Ramezanipour et al., 2005).

In the crystal structure, C—H···Cl interactions are found so that each Cl atom is associated with two H atoms to form supramolecular arrays in the ac plane (Table 1 and Fig. 2). The most prominent interactions between the layers are of the type C═O···π. The closest of these involves the carbonyl-O1 group and the centroid (Cg) of C4–C7, C11, C12 ring [O1···Cgⁱ = 3.110 (8) Å with the C5–O1···Cgⁱ angle being 133.1 (8)°, symmetry code: (i) -1/4+x, 1/4-y, -1/4+z] (Fig. 3).

Related literature top

For related main-group compounds of 1,10-phenanthroline-5,6-dione, see: de Alencastro et al. (2005). For the ligand synthesis, see: Yamada et al. (1992). For a related structure, see: Ramezanipour et al. (2005).

Experimental top

Solutions of HgCl₂ (0.272 mg, 1.0 mmol) in EtOH (5 ml) and of 1,10-phenanthroline-5,6-dione (Yamada et al., 1992) (0.212 mg, 1.0 mmol) in EtOH (20 ml) were mixed and stirred at room temperature for 1 h. The precipitate was collected, washed with small portions of EtOH and petroleum ether and dried (yield 0.330 mg). Analysis, calculated for C₁₂H₆Cl₂HgN₂O₂ [HgCl₂(pdon)]: C 29.9, H 1.3, N 5.8%; found: C 30.2, H 1.5, N 5.2%.

Recrystallization of HgCl₂(pdon) from MeNO₂ solution produced crystals of the title compound, HgCl₂(pdon)₂.

Computing details top

Data collection: COLLECT (Hooft, 1998); cell refinement: DENZO (Otwinowski & Minor, 1997) and COLLECT (Hooft, 1998); data reduction: DENZO (Otwinowski & Minor, 1997) and COLLECT (Hooft, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: publCIF (Westrip, 2009).

Figures top

	Fig. 1. Molecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level. [Symmetry code: (i) -x, -y, z.]
	Fig. 2. Supramolecular array in the ac plane mediated by C—H···Cl contacts (orange dashed lines). [Colour codes: Hg orange; Cl cyan; O red; N blue; C grey; H green.]
	Fig. 3. Unit-cell contents viewed in projection down the a axis. The C—H···Cl contacts are shown as orange dashed lines. [Colour codes: Hg orange; Cl cyan; O red; N blue; C grey; H green.]

Dichloridobis(1,10-phenanthroline-5,6-dione-κ²N,N')mercury(II) top

Crystal data top

[HgCl₂(C₁₂H₆N₂O₂)₂]	F(000) = 2640
M_r = 691.87	D_x = 2.076 Mg m⁻³
Orthorhombic, Fdd2	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: F 2 -2d	Cell parameters from 18660 reflections
a = 8.2261 (2) Å	θ = 2.9–27.5°
b = 42.6761 (11) Å	µ = 7.24 mm⁻¹
c = 12.6108 (3) Å	T = 120 K
V = 4427.12 (19) Å³	Block, yellow
Z = 8	0.20 × 0.10 × 0.06 mm

Data collection top

Nonius KappaCCD diffractometer	2487 independent reflections
Radiation source: Enraf Nonius FR591 rotating anode	2239 reflections with I > 2σ(I)
10 cm confocal mirrors monochromator	R_int = 0.075
Detector resolution: 9.091 pixels mm^-1	θ_max = 27.5°, θ_min = 3.0°
ϕ and ω scans	h = −10→8
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	k = −55→55
T_min = 0.204, T_max = 0.651	l = −16→16
10751 measured reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.037	H-atom parameters constrained
wR(F²) = 0.094	w = 1/[σ²(F_o²) + (0.0564P)² + 3.1352P] where P = (F_o² + 2F_c²)/3
S = 1.05	(Δ/σ)_max < 0.001
2487 reflections	Δρ_max = 2.27 e Å⁻³
159 parameters	Δρ_min = −0.68 e Å⁻³
1 restraint	Absolute structure: Flack (1983), 1163 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: −0.012 (13)

Crystal data top

[HgCl₂(C₁₂H₆N₂O₂)₂]	V = 4427.12 (19) Å³
M_r = 691.87	Z = 8
Orthorhombic, Fdd2	Mo Kα radiation
a = 8.2261 (2) Å	µ = 7.24 mm⁻¹
b = 42.6761 (11) Å	T = 120 K
c = 12.6108 (3) Å	0.20 × 0.10 × 0.06 mm

Data collection top

Nonius KappaCCD diffractometer	2487 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	2239 reflections with I > 2σ(I)
T_min = 0.204, T_max = 0.651	R_int = 0.075
10751 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.037	H-atom parameters constrained
wR(F²) = 0.094	Δρ_max = 2.27 e Å⁻³
S = 1.05	Δρ_min = −0.68 e Å⁻³
2487 reflections	Absolute structure: Flack (1983), 1163 Friedel pairs
159 parameters	Absolute structure parameter: −0.012 (13)
1 restraint

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Hg	0.0000	0.0000	0.48512 (8)	0.04052 (12)
Cl1	0.1811 (2)	0.03035 (5)	0.61020 (15)	0.0486 (4)
O1	−0.3649 (8)	0.12440 (15)	0.2228 (6)	0.072 (2)
O2	−0.0592 (10)	0.12581 (18)	0.1361 (7)	0.081 (2)
N1	−0.2157 (8)	0.03565 (16)	0.4299 (5)	0.0406 (14)
N2	0.0815 (7)	0.03486 (14)	0.3337 (4)	0.0399 (13)
C1	−0.3618 (9)	0.03505 (19)	0.4754 (6)	0.0472 (16)
H1	−0.3840	0.0191	0.5258	0.057*
C2	−0.4837 (9)	0.0567 (2)	0.4528 (7)	0.050 (2)
H2	−0.5869	0.0554	0.4864	0.060*
C3	−0.4507 (11)	0.07993 (18)	0.3806 (6)	0.0459 (17)
H3	−0.5300	0.0955	0.3653	0.055*
C4	−0.3014 (10)	0.08061 (18)	0.3300 (6)	0.0435 (16)
C5	−0.2664 (10)	0.1051 (2)	0.2493 (14)	0.057 (3)
C6	−0.0923 (11)	0.1052 (2)	0.1979 (8)	0.059 (2)
C7	0.0217 (9)	0.0800 (2)	0.2297 (7)	0.0450 (17)
C8	0.1742 (11)	0.0790 (2)	0.1830 (6)	0.0482 (18)
H8	0.2071	0.0945	0.1335	0.058*
C9	0.2777 (9)	0.0545 (2)	0.2110 (6)	0.0453 (18)
H9	0.3818	0.0526	0.1792	0.054*
C10	0.2257 (10)	0.03325 (19)	0.2861 (7)	0.0437 (17)
H10	0.2965	0.0166	0.3047	0.052*
C11	−0.0196 (9)	0.05763 (18)	0.3047 (6)	0.0409 (16)
C12	−0.1850 (9)	0.05809 (16)	0.3578 (7)	0.0413 (14)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Hg	0.03662 (19)	0.04817 (18)	0.03677 (16)	0.00021 (19)	0.000	0.000
Cl1	0.0400 (9)	0.0635 (11)	0.0424 (9)	−0.0042 (8)	−0.0003 (8)	−0.0077 (8)
O1	0.062 (4)	0.064 (4)	0.091 (5)	0.015 (3)	0.005 (4)	0.029 (4)
O2	0.055 (4)	0.082 (5)	0.106 (6)	0.016 (4)	0.016 (4)	0.049 (4)
N1	0.042 (3)	0.046 (3)	0.034 (3)	−0.003 (3)	0.004 (2)	−0.003 (3)
N2	0.035 (3)	0.049 (3)	0.036 (3)	0.003 (3)	0.000 (2)	−0.001 (2)
C1	0.039 (4)	0.064 (4)	0.039 (3)	−0.007 (3)	−0.002 (3)	−0.005 (4)
C2	0.033 (4)	0.069 (5)	0.047 (4)	−0.006 (3)	0.001 (3)	−0.010 (3)
C3	0.044 (4)	0.047 (4)	0.047 (4)	0.006 (3)	−0.004 (3)	−0.011 (3)
C4	0.032 (3)	0.053 (4)	0.045 (4)	0.001 (3)	−0.006 (3)	−0.004 (3)
C5	0.048 (5)	0.055 (4)	0.067 (10)	0.002 (4)	−0.011 (5)	0.012 (5)
C6	0.052 (5)	0.059 (5)	0.067 (5)	0.000 (4)	−0.008 (4)	0.012 (4)
C7	0.044 (4)	0.048 (4)	0.043 (4)	−0.003 (3)	0.004 (3)	−0.001 (3)
C8	0.050 (5)	0.052 (4)	0.043 (4)	−0.004 (3)	−0.001 (3)	0.007 (3)
C9	0.037 (4)	0.062 (5)	0.038 (4)	−0.011 (3)	0.001 (3)	−0.007 (3)
C10	0.047 (5)	0.042 (4)	0.042 (4)	0.005 (3)	−0.007 (3)	−0.001 (3)
C11	0.043 (4)	0.042 (4)	0.038 (3)	0.000 (3)	−0.002 (3)	−0.009 (3)
C12	0.039 (4)	0.040 (3)	0.045 (3)	0.000 (3)	−0.009 (3)	−0.002 (3)

Geometric parameters (Å, º) top

Hg—N1	2.439 (7)	C3—H3	0.9500
Hg—N2	2.512 (6)	C4—C12	1.401 (11)
Hg—Cl1	2.5270 (19)	C4—C5	1.487 (15)
O1—C5	1.203 (11)	C5—C6	1.572 (14)
O2—C6	1.206 (11)	C6—C7	1.483 (12)
N1—C1	1.332 (10)	C7—C11	1.386 (12)
N1—C12	1.344 (10)	C7—C8	1.387 (12)
N2—C11	1.330 (10)	C8—C9	1.392 (12)
N2—C10	1.331 (10)	C8—H8	0.9500
C1—C2	1.393 (12)	C9—C10	1.380 (11)
C1—H1	0.9500	C9—H9	0.9500
C2—C3	1.374 (13)	C10—H10	0.9500
C2—H2	0.9500	C11—C12	1.516 (11)
C3—C4	1.384 (11)

N1—Hg—N1ⁱ	146.8 (3)	C4—C3—H3	120.1
N1—Hg—N2ⁱ	87.6 (2)	C3—C4—C12	118.4 (8)
N1ⁱ—Hg—N2ⁱ	66.9 (2)	C3—C4—C5	120.1 (7)
N1—Hg—N2	66.9 (2)	C12—C4—C5	121.4 (7)
N1ⁱ—Hg—N2	87.6 (2)	O1—C5—C4	122.8 (9)
N2ⁱ—Hg—N2	81.0 (3)	O1—C5—C6	119.8 (11)
N1—Hg—Cl1	106.71 (16)	C4—C5—C6	117.4 (8)
N1ⁱ—Hg—Cl1	93.95 (16)	O2—C6—C7	124.1 (9)
N2ⁱ—Hg—Cl1	159.31 (13)	O2—C6—C5	118.3 (9)
N2—Hg—Cl1	90.78 (14)	C7—C6—C5	117.5 (8)
N1—Hg—Cl1ⁱ	93.95 (16)	C11—C7—C8	119.4 (8)
N1ⁱ—Hg—Cl1ⁱ	106.71 (16)	C11—C7—C6	122.0 (7)
N2ⁱ—Hg—Cl1ⁱ	90.78 (14)	C8—C7—C6	118.6 (8)
N2—Hg—Cl1ⁱ	159.31 (13)	C7—C8—C9	117.9 (8)
Cl1—Hg—Cl1ⁱ	102.75 (10)	C7—C8—H8	121.0
C1—N1—C12	118.3 (7)	C9—C8—H8	121.0
C1—N1—Hg	121.4 (5)	C10—C9—C8	118.6 (7)
C12—N1—Hg	120.0 (5)	C10—C9—H9	120.7
C11—N2—C10	118.1 (7)	C8—C9—H9	120.7
C11—N2—Hg	118.3 (5)	N2—C10—C9	123.5 (7)
C10—N2—Hg	123.4 (5)	N2—C10—H10	118.3
N1—C1—C2	123.3 (8)	C9—C10—H10	118.3
N1—C1—H1	118.4	N2—C11—C7	122.5 (7)
C2—C1—H1	118.4	N2—C11—C12	116.7 (7)
C3—C2—C1	118.2 (7)	C7—C11—C12	120.8 (7)
C3—C2—H2	120.9	N1—C12—C4	122.0 (8)
C1—C2—H2	120.9	N1—C12—C11	117.3 (7)
C2—C3—C4	119.8 (7)	C4—C12—C11	120.7 (7)
C2—C3—H3	120.1

N1ⁱ—Hg—N1—C1	135.2 (6)	C4—C5—C6—C7	2.9 (16)
N2ⁱ—Hg—N1—C1	96.6 (6)	O2—C6—C7—C11	177.0 (10)
N2—Hg—N1—C1	177.8 (6)	C5—C6—C7—C11	−2.3 (14)
Cl1—Hg—N1—C1	−98.6 (6)	O2—C6—C7—C8	−2.6 (15)
Cl1ⁱ—Hg—N1—C1	5.9 (6)	C5—C6—C7—C8	178.0 (9)
N1ⁱ—Hg—N1—C12	−50.0 (5)	C11—C7—C8—C9	2.5 (12)
N2ⁱ—Hg—N1—C12	−88.6 (6)	C6—C7—C8—C9	−177.8 (8)
N2—Hg—N1—C12	−7.4 (5)	C7—C8—C9—C10	−2.2 (12)
Cl1—Hg—N1—C12	76.2 (6)	C11—N2—C10—C9	2.3 (12)
Cl1ⁱ—Hg—N1—C12	−179.2 (5)	Hg—N2—C10—C9	−172.5 (6)
N1—Hg—N2—C11	7.4 (5)	C8—C9—C10—N2	−0.2 (12)
N1ⁱ—Hg—N2—C11	165.7 (5)	C10—N2—C11—C7	−1.9 (11)
N2ⁱ—Hg—N2—C11	98.7 (5)	Hg—N2—C11—C7	173.2 (6)
Cl1—Hg—N2—C11	−100.4 (5)	C10—N2—C11—C12	177.9 (7)
Cl1ⁱ—Hg—N2—C11	30.9 (8)	Hg—N2—C11—C12	−7.0 (8)
N1—Hg—N2—C10	−177.7 (6)	C8—C7—C11—N2	−0.5 (12)
N1ⁱ—Hg—N2—C10	−19.5 (6)	C6—C7—C11—N2	179.8 (8)
N2ⁱ—Hg—N2—C10	−86.5 (6)	C8—C7—C11—C12	179.7 (7)
Cl1—Hg—N2—C10	74.4 (6)	C6—C7—C11—C12	0.0 (12)
Cl1ⁱ—Hg—N2—C10	−154.2 (5)	C1—N1—C12—C4	0.1 (11)
C12—N1—C1—C2	−0.6 (12)	Hg—N1—C12—C4	−174.9 (5)
Hg—N1—C1—C2	174.3 (6)	C1—N1—C12—C11	−178.1 (6)
N1—C1—C2—C3	−0.5 (12)	Hg—N1—C12—C11	6.9 (9)
C1—C2—C3—C4	2.2 (12)	C3—C4—C12—N1	1.6 (11)
C2—C3—C4—C12	−2.7 (11)	C5—C4—C12—N1	−179.4 (9)
C2—C3—C4—C5	178.2 (9)	C3—C4—C12—C11	179.8 (7)
C3—C4—C5—O1	−2.1 (18)	C5—C4—C12—C11	−1.2 (13)
C12—C4—C5—O1	178.8 (11)	N2—C11—C12—N1	0.3 (10)
C3—C4—C5—C6	177.9 (9)	C7—C11—C12—N1	−179.9 (7)
C12—C4—C5—C6	−1.1 (16)	N2—C11—C12—C4	−178.0 (7)
O1—C5—C6—O2	3.5 (19)	C7—C11—C12—C4	1.9 (11)
C4—C5—C6—O2	−176.5 (10)	O1—C5—C6—O2	3.5 (19)
O1—C5—C6—C7	−177.1 (11)

Symmetry code: (i) −x, −y, z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···Cl1ⁱⁱ	0.95	2.69	3.578 (8)	156
C9—H9···Cl1ⁱⁱⁱ	0.95	2.78	3.701 (8)	164

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

Experimental details

Crystal data
Chemical formula	[HgCl₂(C₁₂H₆N₂O₂)₂]
M_r	691.87
Crystal system, space group	Orthorhombic, Fdd2
Temperature (K)	120
a, b, c (Å)	8.2261 (2), 42.6761 (11), 12.6108 (3)
V (Å³)	4427.12 (19)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	7.24
Crystal size (mm)	0.20 × 0.10 × 0.06

Data collection
Diffractometer	Nonius KappaCCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.204, 0.651
No. of measured, independent and observed [I > 2σ(I)] reflections	10751, 2487, 2239
R_int	0.075
(sin θ/λ)_max (Å⁻¹)	0.650

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.094, 1.05
No. of reflections	2487
No. of parameters	159
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	2.27, −0.68
Absolute structure	Flack (1983), 1163 Friedel pairs
Absolute structure parameter	−0.012 (13)

Computer programs: , DENZO (Otwinowski & Minor, 1997) and COLLECT (Hooft, 1998), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 1999), publCIF (Westrip, 2009).

Selected bond lengths (Å) top

Hg—N1	2.439 (7)	Hg—Cl1	2.5270 (19)
Hg—N2	2.512 (6)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···Cl1ⁱ	0.95	2.69	3.578 (8)	156
C9—H9···Cl1ⁱⁱ	0.95	2.78	3.701 (8)	164

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

Footnotes

‡Additional correspondence author, e-mail: j.wardell@abdn.ac.uk.

Acknowledgements

The use of the EPSRC X-ray crystallographic service at the University of Southampton, England, and the valuable assistance of the staff there are gratefully acknowledged. JLW acknowledges support from FAPEMIG (Brazil).

References

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