Bis(2,4-dimethyl-pyridinium) tetra-bromido-mercurate(II).

The asymmetric unit of the title compound, (C7H10N)2[HgBr4], consists of one cation and one half-anion, bis-ected by a twofold rotation axis passing through the metal atom. The anion exhibits a distorted tetra-hedral arrangement about the Hg(II) atom. In the crystal, the cations and anions are linked by N-H⋯Br hydrogen-bonding inter-actions along [010]. Cation-cation π-π stacking and Br⋯Br inter-molecular inter-actions are absent.

Related literature

For inter­molecular inter­actions, see: Desiraju (1997 ▶). For related structures, see: Al-Far & Ali (2007 ▶); Ali & Al-Far (2007 ▶); Ali et al. (2008 ▶). For structures containing the [HgBr4]2− anion, see: Gowda et al. (2009 ▶); Li et al. (2009 ▶). For standard bond lengths in the cation, see: Allen et al. (1987 ▶).

Experimental

Crystal data

(C7H10N)2[HgBr4]

M = 736.51

Monoclinic,

a = 20.022 (5) Å

b = 7.7985 (9) Å

c = 17.651 (3) Å

β = 129.12 (3)°

V = 2138.1 (11) Å3

Z = 4

Mo Kα radiation

μ = 14.67 mm−1

T = 293 K

0.44 × 0.40 × 0.18 mm

Data collection

Agilent Xcalibur Eos diffractometer

Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011 ▶) T min = 0.002, T max = 0.072

5366 measured reflections

2895 independent reflections

1454 reflections with I > 2σ(I)

R int = 0.036

Refinement

R[F 2 > 2σ(F 2)] = 0.050

wR(F 2) = 0.102

S = 1.01

2895 reflections

98 parameters

H-atom parameters constrained

Δρmax = 1.45 e Å−3

Δρmin = −1.54 e Å−3

Data collection: CrysAlis PRO (Agilent, 2011 ▶); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Click here for additional data file.

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536812046788/bx2429sup1.cif

Click here for additional data file.

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812046788/bx2429Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

(C7H10N)2[HgBr4]	F(000) = 1352
Mr = 736.51	Dx = 2.288 Mg m−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 1281 reflections
a = 20.022 (5) Å	θ = 2.9–29.1°
b = 7.7985 (9) Å	µ = 14.67 mm−1
c = 17.651 (3) Å	T = 293 K
β = 129.12 (3)°	Block, colourless
V = 2138.1 (11) Å3	0.44 × 0.40 × 0.18 mm
Z = 4

Agilent Xcalibur Eos diffractometer	2895 independent reflections
Radiation source: Enhance (Mo) X-ray Source	1454 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.036
Detector resolution: 16.0534 pixels mm-1	θmax = 29.2°, θmin = 2.9°
ω scans	h = −27→26
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011)	k = −6→10
Tmin = 0.002, Tmax = 0.072	l = −24→16
5366 measured reflections

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)] = 0.050	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.102	H-atom parameters constrained
S = 1.01	w = 1/[σ2(Fo2) + (0.0354P)2] where P = (Fo2 + 2Fc2)/3
2895 reflections	(Δ/σ)max < 0.001
98 parameters	Δρmax = 1.45 e Å−3
0 restraints	Δρmin = −1.54 e Å−3

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.

	x	y	z	Uiso*/Ueq
Hg1	0.5000	0.17233 (6)	0.7500	0.0544 (2)
Br1	0.54606 (6)	0.33656 (12)	0.90297 (6)	0.0647 (3)
N1	0.3078 (5)	0.0541 (10)	0.9729 (5)	0.066 (2)
H1A	0.3343	0.0396	1.0342	0.080*
C1	0.3507 (5)	0.1249 (10)	0.9458 (6)	0.050 (2)
Br2	0.36889 (6)	−0.01976 (14)	0.69426 (7)	0.0796 (4)
C2	0.3064 (5)	0.1449 (10)	0.8472 (6)	0.053 (2)
H2A	0.3348	0.1915	0.8260	0.064*
C3	0.2217 (6)	0.0982 (11)	0.7793 (6)	0.054 (2)
C4	0.1817 (6)	0.0263 (12)	0.8122 (7)	0.076 (3)
H4A	0.1244	−0.0076	0.7677	0.091*
C5	0.2249 (6)	0.0046 (14)	0.9087 (7)	0.086 (3)
H5A	0.1976	−0.0443	0.9308	0.103*
C6	0.4414 (6)	0.1759 (12)	1.0245 (6)	0.078 (3)
H6A	0.4433	0.2624	1.0646	0.116*
H6B	0.4658	0.2205	0.9961	0.116*
H6C	0.4739	0.0777	1.0639	0.116*
C7	0.1732 (6)	0.1298 (12)	0.6723 (6)	0.078 (3)
H7A	0.1294	0.0438	0.6351	0.118*
H7B	0.2122	0.1247	0.6581	0.118*
H7C	0.1468	0.2411	0.6553	0.118*

	U11	U22	U33	U12	U13	U23
Hg1	0.0559 (3)	0.0639 (4)	0.0459 (3)	0.000	0.0334 (2)	0.000
Br1	0.0707 (6)	0.0762 (8)	0.0504 (5)	−0.0070 (5)	0.0398 (5)	−0.0130 (5)
N1	0.066 (5)	0.079 (6)	0.057 (5)	0.005 (4)	0.040 (4)	0.015 (4)
C1	0.058 (6)	0.044 (6)	0.055 (5)	0.001 (4)	0.039 (5)	−0.001 (4)
Br2	0.0820 (7)	0.1058 (9)	0.0702 (6)	−0.0375 (6)	0.0572 (6)	−0.0225 (6)
C2	0.057 (6)	0.056 (6)	0.053 (5)	−0.003 (4)	0.038 (5)	−0.002 (4)
C3	0.059 (6)	0.041 (5)	0.052 (5)	0.003 (4)	0.030 (5)	0.000 (4)
C4	0.050 (6)	0.084 (8)	0.065 (6)	−0.012 (5)	0.023 (5)	0.011 (6)
C5	0.058 (7)	0.111 (10)	0.087 (8)	0.005 (6)	0.046 (6)	0.029 (7)
C6	0.053 (6)	0.100 (9)	0.064 (6)	−0.012 (5)	0.030 (5)	−0.003 (6)
C7	0.078 (7)	0.087 (8)	0.053 (5)	0.013 (6)	0.033 (5)	0.010 (5)

Hg1—Br1	2.5767 (11)	C3—C4	1.372 (12)
Hg1—Br1i	2.5767 (10)	C3—C7	1.502 (11)
Hg1—Br2	2.6160 (11)	C4—C5	1.349 (11)
Hg1—Br2i	2.6160 (11)	C4—H4A	0.9300
N1—C1	1.338 (9)	C5—H5A	0.9300
N1—C5	1.347 (10)	C6—H6A	0.9600
N1—H1A	0.8600	C6—H6B	0.9600
C1—C2	1.376 (10)	C6—H6C	0.9600
C1—C6	1.485 (11)	C7—H7A	0.9600
C2—C3	1.372 (10)	C7—H7B	0.9600
C2—H2A	0.9300	C7—H7C	0.9600
Br1—Hg1—Br1i	120.39 (5)	C5—C4—C3	120.4 (9)
Br1—Hg1—Br2	106.83 (4)	C5—C4—H4A	119.8
Br1i—Hg1—Br2	106.25 (5)	C3—C4—H4A	119.8
Br1—Hg1—Br2i	106.25 (5)	N1—C5—C4	119.6 (9)
Br1i—Hg1—Br2i	106.83 (4)	N1—C5—H5A	120.2
Br2—Hg1—Br2i	110.13 (6)	C4—C5—H5A	120.2
C1—N1—C5	123.1 (8)	C1—C6—H6A	109.5
C1—N1—H1A	118.5	C1—C6—H6B	109.5
C5—N1—H1A	118.5	H6A—C6—H6B	109.5
N1—C1—C2	116.9 (8)	C1—C6—H6C	109.5
N1—C1—C6	117.3 (8)	H6A—C6—H6C	109.5
C2—C1—C6	125.8 (8)	H6B—C6—H6C	109.5
C3—C2—C1	122.0 (8)	C3—C7—H7A	109.5
C3—C2—H2A	119.0	C3—C7—H7B	109.5
C1—C2—H2A	119.0	H7A—C7—H7B	109.5
C2—C3—C4	118.0 (8)	C3—C7—H7C	109.5
C2—C3—C7	121.2 (8)	H7A—C7—H7C	109.5
C4—C3—C7	120.8 (9)	H7B—C7—H7C	109.5
C5—N1—C1—C2	−0.5 (13)	C1—C2—C3—C7	176.6 (7)
C5—N1—C1—C6	179.1 (9)	C2—C3—C4—C5	0.6 (15)
N1—C1—C2—C3	1.3 (12)	C7—C3—C4—C5	−177.4 (9)
C6—C1—C2—C3	−178.3 (8)	C1—N1—C5—C4	−0.1 (15)
C1—C2—C3—C4	−1.4 (13)	C3—C4—C5—N1	0.1 (16)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···Br2ii	0.86	2.45	3.286 (7)	163

Table 1

Selected bond lengths (Å)

Hg1—Br1	2.5767 (11)
Hg1—Br2	2.6160 (11)

Table 2

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯Br2i	0.86	2.45	3.286 (7)	163

Symmetry code: (i) .