μ-2,3,5,6-Tetra-2-pyridylpyrazine-bis­[dichloro­mercury(II)]

The title complex, μ-2,3,5,6-tetra-2-pyridylpyrazine-κ⁴N²,N⁶:N³,N⁵-bis­[dichloro­mercury(II)], [Hg₂Cl₄(C₂₄H₁₆N₆)], displays a centrosymmetric dinuclear structure, in which the 2,3,5,6-tetra-2-pyridylpyrazine ligand coordinates in a bis-tridentate bridging manner to link two Hg ions that adopt a distorted octa­hedral coordination geometry including weak inter­molecular Hg...Cl coordination.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.008 Å
• R factor = 0.026
• wR factor = 0.065
• Data-to-parameter ratio = 15.0

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT213_ALERT_2_B Atom C8      has ADP max/min Ratio .............       4.10 oblate

Alert level C
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low .......       0.97
PLAT432_ALERT_2_C Short Inter X...Y Contact  N2     ..  C10     ..       3.01 Ang.

   0 ALERT level A = In general: serious problem
   1 ALERT level B = Potentially serious problem
   2 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

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

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Computing details

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT and SHELXTL (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97; molecular graphics: SHELXTL (Bruker, 1998); software used to prepare material for publication: SHELXTL.

µ-2,3,5,6-tetra-2-pyridylpyrazine-κ⁴N²,N⁶:N³,N⁵– bis[dichloromercury(II)]

Crystal data

[Hg2Cl4(C24H16N6)]	Z = 1
Mr = 931.41	F(000) = 430
Triclinic, P1	Dx = 2.406 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.2045 (8) Å	Cell parameters from 3118 reflections
b = 9.1939 (10) Å	θ = 2.5–28.2°
c = 11.2326 (13) Å	µ = 12.37 mm^−1
α = 111.030 (2)°	T = 100 K
β = 97.764 (2)°	Block, colorless
γ = 106.370 (2)°	0.22 × 0.20 × 0.20 mm
V = 642.71 (12) Å^3

Data collection

Bruker SMART 1000 CCD area-detector diffractometer	2442 independent reflections
Radiation source: fine-focus sealed tube	2341 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.028
φ and ω scans	θmax = 26.0°, θmin = 2.0°
Absorption correction: multi-scan (SADABS; Bruker, 1998)	h = −8→6
Tmin = 0.076, Tmax = 0.084	k = −10→11
3571 measured reflections	l = −12→13

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)] = 0.026	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.065	H-atom parameters constrained
S = 1.11	w = 1/[σ^2(Fo^2) + (0.0235P)^2] where P = (Fo^2 + 2Fc^2)/3
2442 reflections	(Δ/σ)max = 0.001
163 parameters	Δρmax = 1.80 e Å^−3
0 restraints	Δρmin = −1.73 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
Hg1	0.51558 (3)	0.89271 (2)	0.794700 (17)	0.01326 (9)
Cl1	0.7508 (2)	1.05584 (17)	0.72350 (13)	0.0192 (3)
Cl2	0.2651 (2)	0.82444 (17)	0.90348 (12)	0.0176 (3)
N1	0.7036 (7)	0.7224 (5)	0.8547 (4)	0.0137 (9)
N2	0.4581 (6)	0.6051 (5)	0.6046 (4)	0.0106 (9)
N3	0.2337 (7)	0.7884 (6)	0.5776 (4)	0.0158 (10)
C1	0.7775 (8)	0.7596 (7)	0.9836 (5)	0.0197 (12)
H1A	0.8160	0.8717	1.0468	0.024*
C2	0.7988 (9)	0.6426 (7)	1.0264 (5)	0.0194 (12)
H2A	0.8547	0.6746	1.1176	0.023*
C3	0.7395 (8)	0.4774 (7)	0.9377 (5)	0.0191 (12)
H3A	0.7479	0.3940	0.9670	0.023*
C4	0.6672 (8)	0.4371 (7)	0.8041 (5)	0.0146 (11)
H4A	0.6250	0.3253	0.7397	0.017*
C5	0.6584 (7)	0.5649 (6)	0.7675 (5)	0.0110 (10)
C6	0.5857 (7)	0.5305 (6)	0.6258 (5)	0.0104 (10)
C7	0.3656 (8)	0.5736 (7)	0.4808 (5)	0.0116 (10)
C8	0.2087 (8)	0.6491 (6)	0.4730 (5)	0.0111 (10)
C9	0.0380 (8)	0.5693 (7)	0.3672 (5)	0.0135 (10)
H9A	0.0215	0.4680	0.2956	0.016*
C10	−0.1072 (8)	0.6409 (7)	0.3686 (5)	0.0160 (11)
H10A	−0.2235	0.5909	0.2965	0.019*
C11	−0.0818 (8)	0.7854 (7)	0.4757 (5)	0.0177 (11)
H11A	−0.1791	0.8371	0.4782	0.021*
C12	0.0892 (8)	0.8536 (7)	0.5797 (5)	0.0183 (12)
H12A	0.1043	0.9504	0.6554	0.022*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Hg1	0.01572 (13)	0.01262 (13)	0.01327 (12)	0.00585 (9)	0.00515 (8)	0.00635 (9)
Cl1	0.0226 (7)	0.0162 (7)	0.0226 (7)	0.0065 (6)	0.0113 (5)	0.0106 (6)
Cl2	0.0192 (7)	0.0177 (7)	0.0140 (6)	0.0043 (5)	0.0058 (5)	0.0059 (5)
N1	0.016 (2)	0.017 (2)	0.010 (2)	0.0090 (19)	0.0034 (17)	0.0051 (19)
N2	0.010 (2)	0.009 (2)	0.013 (2)	0.0011 (17)	0.0045 (16)	0.0060 (18)
N3	0.022 (2)	0.017 (2)	0.015 (2)	0.012 (2)	0.0069 (18)	0.008 (2)
C1	0.019 (3)	0.024 (3)	0.015 (3)	0.008 (2)	0.003 (2)	0.007 (2)
C2	0.023 (3)	0.023 (3)	0.012 (3)	0.007 (3)	0.002 (2)	0.008 (2)
C3	0.021 (3)	0.024 (3)	0.021 (3)	0.008 (2)	0.008 (2)	0.017 (3)
C4	0.013 (3)	0.017 (3)	0.016 (3)	0.005 (2)	0.003 (2)	0.009 (2)
C5	0.006 (2)	0.013 (3)	0.015 (3)	0.003 (2)	0.0035 (19)	0.006 (2)
C6	0.009 (2)	0.006 (2)	0.016 (2)	0.0001 (19)	0.0010 (19)	0.007 (2)
C7	0.013 (3)	0.015 (3)	0.012 (2)	0.007 (2)	0.0063 (19)	0.010 (2)
C8	0.015 (3)	0.011 (2)	0.015 (2)	0.005 (2)	0.008 (2)	0.012 (2)
C9	0.015 (3)	0.014 (3)	0.013 (2)	0.005 (2)	0.006 (2)	0.007 (2)
C10	0.013 (3)	0.025 (3)	0.018 (3)	0.007 (2)	0.007 (2)	0.017 (2)
C11	0.015 (3)	0.023 (3)	0.023 (3)	0.009 (2)	0.009 (2)	0.015 (2)
C12	0.019 (3)	0.018 (3)	0.021 (3)	0.010 (2)	0.006 (2)	0.009 (2)

Geometric parameters (Å, º)

Hg1—Cl1	2.3569 (14)	C3—H3A	0.9500
Hg1—Cl2	2.3773 (14)	C4—C5	1.391 (7)
Hg1—N1	2.539 (4)	C4—H4A	0.9500
Hg1—N2	2.610 (4)	C5—C6	1.492 (7)
Hg1—N3	2.622 (4)	C6—C7^i	1.397 (7)
N1—C5	1.339 (7)	C7—C6^i	1.397 (7)
N1—C1	1.353 (6)	C7—C8	1.492 (7)
N2—C6	1.337 (6)	C8—C9	1.391 (7)
N2—C7	1.347 (6)	C9—C10	1.383 (7)
N3—C8	1.336 (7)	C9—H9A	0.9500
N3—C12	1.338 (7)	C10—C11	1.379 (8)
C1—C2	1.362 (8)	C10—H10A	0.9500
C1—H1A	0.9500	C11—C12	1.388 (7)
C2—C3	1.384 (8)	C11—H11A	0.9500
C2—H2A	0.9500	C12—H12A	0.9500
C3—C4	1.394 (7)
Cl1—Hg1—Cl2	158.88 (5)	C5—C4—C3	118.2 (5)
Cl1—Hg1—N1	101.93 (11)	C5—C4—H4A	120.9
Cl1—Hg1—N2	96.42 (10)	C3—C4—H4A	120.9
Cl1—Hg1—N3	92.20 (11)	N1—C5—C4	123.3 (5)
Cl2—Hg1—N1	93.95 (11)	N1—C5—C6	115.8 (4)
Cl2—Hg1—N2	102.98 (10)	C4—C5—C6	120.9 (4)
Cl2—Hg1—N3	89.52 (11)	N2—C6—C7^i	120.0 (5)
N1—Hg1—N2	64.68 (13)	N2—C6—C5	114.0 (4)
N1—Hg1—N3	126.19 (14)	C7^i—C6—C5	125.9 (4)
N2—Hg1—N3	62.25 (13)	N2—C7—C6^i	119.1 (4)
C5—N1—C1	117.3 (4)	N2—C7—C8	114.4 (4)
C5—N1—Hg1	117.8 (3)	C6^i—C7—C8	126.5 (5)
C1—N1—Hg1	119.3 (3)	N3—C8—C9	122.4 (5)
C6—N2—C7	120.8 (4)	N3—C8—C7	116.3 (4)
C6—N2—Hg1	115.6 (3)	C9—C8—C7	121.0 (5)
C7—N2—Hg1	118.4 (3)	C10—C9—C8	118.5 (5)
C8—N3—C12	118.5 (5)	C10—C9—H9A	120.8
C8—N3—Hg1	120.3 (3)	C8—C9—H9A	120.8
C12—N3—Hg1	119.7 (3)	C11—C10—C9	119.5 (5)
N1—C1—C2	122.5 (5)	C11—C10—H10A	120.3
N1—C1—H1A	118.7	C9—C10—H10A	120.3
C2—C1—H1A	118.7	C10—C11—C12	118.5 (5)
C1—C2—C3	120.3 (5)	C10—C11—H11A	120.8
C1—C2—H2A	119.9	C12—C11—H11A	120.8
C3—C2—H2A	119.9	N3—C12—C11	122.5 (5)
C2—C3—C4	118.0 (5)	N3—C12—H12A	118.7
C2—C3—H3A	121.0	C11—C12—H12A	118.7
C4—C3—H3A	121.0
Cl1—Hg1—N1—C5	−100.7 (4)	C1—N1—C5—C6	−177.5 (5)
Cl2—Hg1—N1—C5	93.3 (4)	Hg1—N1—C5—C6	29.0 (6)
N2—Hg1—N1—C5	−9.1 (4)	C3—C4—C5—N1	−4.5 (8)
N3—Hg1—N1—C5	1.1 (4)	C3—C4—C5—C6	179.0 (5)
Cl1—Hg1—N1—C1	106.3 (4)	C7—N2—C6—C7^i	4.0 (8)
Cl2—Hg1—N1—C1	−59.7 (4)	Hg1—N2—C6—C7^i	−150.0 (4)
N2—Hg1—N1—C1	−162.2 (5)	C7—N2—C6—C5	−173.9 (4)
N3—Hg1—N1—C1	−152.0 (4)	Hg1—N2—C6—C5	32.1 (5)
Cl1—Hg1—N2—C6	86.9 (3)	N1—C5—C6—N2	−41.4 (6)
Cl2—Hg1—N2—C6	−101.5 (3)	C4—C5—C6—N2	135.4 (5)
N1—Hg1—N2—C6	−13.2 (3)	N1—C5—C6—C7^i	140.9 (5)
N3—Hg1—N2—C6	176.0 (4)	C4—C5—C6—C7^i	−42.3 (8)
Cl1—Hg1—N2—C7	−67.8 (4)	C6—N2—C7—C6^i	−4.0 (8)
Cl2—Hg1—N2—C7	103.8 (4)	Hg1—N2—C7—C6^i	149.4 (4)
N1—Hg1—N2—C7	−168.0 (4)	C6—N2—C7—C8	172.5 (4)
N3—Hg1—N2—C7	21.3 (3)	Hg1—N2—C7—C8	−34.1 (5)
Cl1—Hg1—N3—C8	90.5 (4)	C12—N3—C8—C9	−0.4 (8)
Cl2—Hg1—N3—C8	−110.6 (4)	Hg1—N3—C8—C9	166.0 (4)
N1—Hg1—N3—C8	−16.0 (5)	C12—N3—C8—C7	−174.9 (5)
N2—Hg1—N3—C8	−5.6 (4)	Hg1—N3—C8—C7	−8.5 (6)
Cl1—Hg1—N3—C12	−103.3 (4)	N2—C7—C8—N3	27.9 (6)
Cl2—Hg1—N3—C12	55.7 (4)	C6^i—C7—C8—N3	−155.8 (5)
N1—Hg1—N3—C12	150.2 (4)	N2—C7—C8—C9	−146.6 (5)
N2—Hg1—N3—C12	160.6 (4)	C6^i—C7—C8—C9	29.6 (8)
C5—N1—C1—C2	−2.7 (8)	N3—C8—C9—C10	2.5 (8)
Hg1—N1—C1—C2	150.5 (5)	C7—C8—C9—C10	176.7 (5)
N1—C1—C2—C3	−1.7 (9)	C8—C9—C10—C11	−1.9 (8)
C1—C2—C3—C4	3.0 (9)	C9—C10—C11—C12	−0.6 (8)
C2—C3—C4—C5	−0.1 (8)	C8—N3—C12—C11	−2.3 (8)
C1—N1—C5—C4	5.8 (8)	Hg1—N3—C12—C11	−168.7 (4)
Hg1—N1—C5—C4	−147.8 (4)	C10—C11—C12—N3	2.8 (9)

Symmetry code: (i) −x+1, −y+1, −z+1.