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In the title compound, [Ag(C4H4N2)]ClO4, pyrazine ligands bridge two symmetry-related Ag atoms [Ag—N = 2.222 (3) Å] to form linear polycationic chains which run along the c axis of the ortho­rhom­bic unit cell. The AgI ion has m2m site symmetry. The N atoms of the pyrazine ligand lie on a crystallographic mirror plane and each C atom of this ligand possesses crystallographically imposed disorder with two components of equal occupancy. The Cl atom of the perchlorate anion has m2m site symmetry and the two unique O atoms of this anion lie on a mirror plane. In addition, in the crystal structure, one-dimensional chains are linked through weak inter­actions involving perchlorate anions [Ag...O = 2.726 (2) Å] into a motif that can be described as a 4(4).6(2) sheet.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807048969/lh2524sup1.cif
Contains datablocks global, I

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S1600536807048969/lh2524Isup2.hkl
Contains datablock I

CCDC reference: 667142

Key indicators

  • Single-crystal X-ray study
  • T = 295 K
  • Mean [sigma](l-O) = 0.003 Å
  • Disorder in main residue
  • R factor = 0.021
  • wR factor = 0.052
  • Data-to-parameter ratio = 10.7

checkCIF/PLATON results

No syntax errors found



Alert level B PLAT242_ALERT_2_B Check Low Ueq as Compared to Neighbors for Cl1 PLAT301_ALERT_3_B Main Residue Disorder ......................... 29.00 Perc.
Alert level C PLAT062_ALERT_4_C Rescale T(min) & T(max) by ..................... 0.95 PLAT764_ALERT_4_C Overcomplete CIF Bond List Detected (Rep/Expd) . 1.27 Ratio
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 H4 Ag1 Cl1 N2 O4 Atom count from _chemical_formula_moiety:C4 H4 Ag1 Cl1 N2 O1
0 ALERT level A = In general: serious problem 2 ALERT level B = Potentially serious problem 2 ALERT level C = Check and explain 1 ALERT level G = General alerts; check 1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 1 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 2 ALERT type 4 Improvement, methodology, query or suggestion 0 ALERT type 5 Informative message, check

Comment top

Silver salts react with the bidentate pyrazine N-heterocycles to furnish adducts that display a diverse range of architectures. The nitrate adduct consists of a polycationic [Ag(C4H4N2)] chain that is surrounded by the nitrate anions, albeit at somewhat long distances (Vranka & Amma, 1966). In silver nitrite adduct, the anion is much closer to the metal atom, the anion chelating to it (Blake et al., 1999) in the resulting pyrazine-bridged chain. With the hexafluorophosphate counterion, the adduct exists as a chain as the counterion is not Lewis-basic enough to have any coordinating ability. One adduct shows the chain motif in whcih the silver atom shows linear coordination; another is a cocrystal that has both [Ag(C4H4N2)] and [Ag2(C4H4N2)5] chains (Carlucci et al., 1995a). Another adduct has the silver in a four-coordinate N4Ag environment (Carlucci et al., 1995b). The silver tetrafluoroborate adduct exists in two forms. One form has polycationic chains and non-interacting tetrafluoroborate anions; in other polymorphs, the silver atom shows three- and four-coordinate heterocycle-linked silver (Carlucci et al., 1995c).

Related literature top

For details of the silver nitrite–pyrazine, see Blake et al. (1999); for the silver hexafluorophosphate–pyrazine, see Carlucci et al. (1995a,b); for the silver tetrafluoroborate–pyrazine, see Carlucci et al. (1995c); and for the silver nitrate–pyrazine adducts, see Vranka & Amma (1966).

Experimental top

Silver perchlorate (0.207 g, 1 mmol), pyrazine (0.08 g, 1 mmol) and water (10 ml) were sealed in a Teflon-lined stainless-steel autoclave (20 ml capacity). The autoclave was heated 433 K for 3 days. It was then cooled at 5 K h-1. Colorless crystals were obtained in about 60% yield based on Ag.

Refinement top

The pyrazine molecule is disordered with respect to the carbon atoms, which were refined as four atoms, each of half-site occupancy. The four carbon-bound H atoms were placed at calculated positions (C–H 0.93 Å) and were included in the refinement in the riding model approximation, with U(H) set to 1.2 times Ueq(C).

Structure description top

Silver salts react with the bidentate pyrazine N-heterocycles to furnish adducts that display a diverse range of architectures. The nitrate adduct consists of a polycationic [Ag(C4H4N2)] chain that is surrounded by the nitrate anions, albeit at somewhat long distances (Vranka & Amma, 1966). In silver nitrite adduct, the anion is much closer to the metal atom, the anion chelating to it (Blake et al., 1999) in the resulting pyrazine-bridged chain. With the hexafluorophosphate counterion, the adduct exists as a chain as the counterion is not Lewis-basic enough to have any coordinating ability. One adduct shows the chain motif in whcih the silver atom shows linear coordination; another is a cocrystal that has both [Ag(C4H4N2)] and [Ag2(C4H4N2)5] chains (Carlucci et al., 1995a). Another adduct has the silver in a four-coordinate N4Ag environment (Carlucci et al., 1995b). The silver tetrafluoroborate adduct exists in two forms. One form has polycationic chains and non-interacting tetrafluoroborate anions; in other polymorphs, the silver atom shows three- and four-coordinate heterocycle-linked silver (Carlucci et al., 1995c).

For details of the silver nitrite–pyrazine, see Blake et al. (1999); for the silver hexafluorophosphate–pyrazine, see Carlucci et al. (1995a,b); for the silver tetrafluoroborate–pyrazine, see Carlucci et al. (1995c); and for the silver nitrate–pyrazine adducts, see Vranka & Amma (1966).

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: APEX2 (Bruker, 2005); data reduction: SAINT (Bruker 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: X-SEED (Barbour, 2001) and OLEX (Dolomanov et al., 2003); software used to prepare material for publication: publCIF (Westrip, 2007).

Figures top
[Figure 1] Fig. 1. Thermal ellipsoid plot of a portion of the chain structure; displacement ellipsoids are drawn at the 50% probability level. Hydrogen atoms are drawn as spheres of arbitrary radii. The weak Ag..Operchlorate interactions are depicted as dashed lines. [Symmetry code: i = x, y, 1/2 - z; ii = 1 - x, y, z.]
[Figure 2] Fig. 2. Layer structure as illustrated by OLEX (Dolomanov et al., 2003).
catena-Poly[[silver(I)-µ-pyrazine-κ2N:N'] perchlorate] top
Crystal data top
[Ag(C4H4N2)]ClO4F(000) = 552
Mr = 287.41Dx = 2.468 Mg m3
Orthorhombic, CmcmMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2c 2Cell parameters from 1486 reflections
a = 7.4838 (2) Åθ = 2.8–27.8°
b = 7.1954 (2) ŵ = 2.93 mm1
c = 14.3623 (4) ÅT = 295 K
V = 773.39 (4) Å3Block, colorless
Z = 40.29 × 0.23 × 0.18 mm
Data collection top
Bruker APEXII area-detector
diffractometer
493 independent reflections
Radiation source: fine-focus sealed tube443 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.023
φ and ω scansθmax = 27.5°, θmin = 2.8°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 89
Tmin = 0.489, Tmax = 0.621k = 97
2749 measured reflectionsl = 1816
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.021H-atom parameters constrained
wR(F2) = 0.052 w = 1/[σ2(Fo2) + (0.0321P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.08(Δ/σ)max = 0.001
493 reflectionsΔρmax = 0.46 e Å3
46 parametersΔρmin = 0.36 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 1997), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0057 (6)
Crystal data top
[Ag(C4H4N2)]ClO4V = 773.39 (4) Å3
Mr = 287.41Z = 4
Orthorhombic, CmcmMo Kα radiation
a = 7.4838 (2) ŵ = 2.93 mm1
b = 7.1954 (2) ÅT = 295 K
c = 14.3623 (4) Å0.29 × 0.23 × 0.18 mm
Data collection top
Bruker APEXII area-detector
diffractometer
493 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
443 reflections with I > 2σ(I)
Tmin = 0.489, Tmax = 0.621Rint = 0.023
2749 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0210 restraints
wR(F2) = 0.052H-atom parameters constrained
S = 1.08Δρmax = 0.46 e Å3
493 reflectionsΔρmin = 0.36 e Å3
46 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
Ag10.50000.05768 (4)0.25000.0418 (2)
Cl10.00000.0621 (1)0.25000.0397 (3)
O10.1546 (3)0.1779 (3)0.25000.0588 (7)
O20.00000.0517 (4)0.3301 (3)0.093 (1)
N10.50000.0229 (4)0.40375 (18)0.0366 (6)
C10.6234 (7)0.0790 (6)0.4472 (3)0.046 (1)0.50
H10.71330.13510.41250.055*0.50
C20.6208 (7)0.1030 (7)0.5424 (3)0.046 (1)0.50
H20.70710.17830.56970.055*0.50
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Ag10.0551 (3)0.0518 (3)0.0186 (2)0.0000.0000.000
Cl10.0362 (6)0.0377 (6)0.0452 (7)0.0000.0000.000
O10.036 (2)0.056 (2)0.084 (2)0.007 (1)0.0000.000
O20.085 (2)0.096 (3)0.097 (3)0.0000.0000.054 (2)
N10.043 (1)0.044 (1)0.023 (1)0.0000.0000.003 (1)
C10.046 (3)0.064 (3)0.028 (2)0.016 (2)0.005 (2)0.002 (2)
C20.047 (3)0.061 (3)0.029 (2)0.020 (2)0.000 (2)0.005 (2)
Geometric parameters (Å, º) top
Ag1—N12.222 (3)N1—C2iv1.322 (5)
Ag1—N1i2.222 (3)N1—C2v1.322 (5)
Ag1—O12.726 (2)N1—C1ii1.334 (5)
Ag1—O1ii2.726 (2)N1—C11.334 (5)
Cl1—O2i1.412 (3)C1—C21.377 (7)
Cl1—O21.412 (3)C2—N1v1.322 (5)
Cl1—O11.426 (2)C1—H10.9300
Cl1—O1iii1.426 (2)C2—H20.9300
N1i—Ag1—N1167.1 (1)C2v—N1—C1ii59.5 (3)
N1—Ag1—O192.05 (2)C2iv—N1—C159.5 (3)
N1—Ag1—O1ii92.05 (2)C2v—N1—C1116.0 (3)
N1i—Ag1—O192.05 (2)C1ii—N1—C187.6 (4)
N1i—Ag1—O1ii92.05 (2)C2iv—N1—Ag1122.2 (2)
O1—Ag1—O1ii143.0 (1)C2v—N1—Ag1122.2 (2)
O1—Cl1—O1iii108.5 (2)C1ii—N1—Ag1121.8 (2)
O1—Cl1—O2109.8 (1)C1—N1—Ag1121.8 (2)
O1—Cl1—O2i109.8 (1)N1—C1—C2121.6 (4)
O1iii—Cl1—O2109.8 (1)N1v—C2—C1122.4 (4)
O1iii—Cl1—O2i109.8 (1)N1—C1—H1119.2
O2—Cl1—O2i109.1 (3)C2—C1—H1119.2
Cl1—O1—Ag1125.8 (1)N1v—C2—H2118.8
C2iv—N1—C2v86.3 (5)C1—C2—H2118.8
C2iv—N1—C1ii116.0 (3)
O2i—Cl1—O1—Ag160.0 (2)N1i—Ag1—N1—C1ii54.5 (3)
O2—Cl1—O1—Ag160.0 (2)O1ii—Ag1—N1—C1ii162.9 (3)
O1iii—Cl1—O1—Ag1180.0O1—Ag1—N1—C1ii53.9 (3)
N1i—Ag1—O1—Cl183.87 (6)N1i—Ag1—N1—C154.5 (3)
N1—Ag1—O1—Cl183.87 (6)O1ii—Ag1—N1—C153.9 (3)
O1ii—Ag1—O1—Cl1180.0O1—Ag1—N1—C1162.9 (3)
N1i—Ag1—N1—C2iv126.1 (3)C2iv—N1—C1—C270.1 (4)
O1ii—Ag1—N1—C2iv17.7 (3)C2v—N1—C1—C21.9 (7)
O1—Ag1—N1—C2iv125.5 (3)C1ii—N1—C1—C252.2 (6)
N1i—Ag1—N1—C2v126.1 (3)Ag1—N1—C1—C2178.7 (3)
O1ii—Ag1—N1—C2v125.5 (3)N1—C1—C2—N1v2.0 (8)
O1—Ag1—N1—C2v17.7 (3)
Symmetry codes: (i) x, y, z+1/2; (ii) x+1, y, z; (iii) x, y, z; (iv) x, y, z+1; (v) x+1, y, z+1.

Experimental details

Crystal data
Chemical formula[Ag(C4H4N2)]ClO4
Mr287.41
Crystal system, space groupOrthorhombic, Cmcm
Temperature (K)295
a, b, c (Å)7.4838 (2), 7.1954 (2), 14.3623 (4)
V3)773.39 (4)
Z4
Radiation typeMo Kα
µ (mm1)2.93
Crystal size (mm)0.29 × 0.23 × 0.18
Data collection
DiffractometerBruker APEXII area-detector
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.489, 0.621
No. of measured, independent and
observed [I > 2σ(I)] reflections
2749, 493, 443
Rint0.023
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.021, 0.052, 1.08
No. of reflections493
No. of parameters46
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.46, 0.36

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker 2005), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), X-SEED (Barbour, 2001) and OLEX (Dolomanov et al., 2003), publCIF (Westrip, 2007).

 

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