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metal-organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 65| Part 2| February 2009| Page m148
doi:10.1107/S1600536808044206

Bis(pyridine-3-carboxylic acid-κN)silver(I) perchlorate

Xiao-Yan Niea and Qian-Zhu Lia*

aDepartment of Chemistry, Bijie University, Bijie 551700, People's Republic of China
*Correspondence e-mail: liqz75@yahoo.com.cn

(Received 18 December 2008; accepted 30 December 2008; online 8 January 2009)

In the title compound, [Ag(C6H5NO2)2]ClO4, the AgI atom shows an almost linear coordination geometry, defined by two N atoms from two pyridine-3-carboxylic acid ligands. The complex cations are linked by hydrogen bonds between the carboxyl groups into a chain. The chains are further connected through C—H⋯O hydrogen bonds and a weak Ag⋯O inter­action [2.757 (8) Å] into a layer. Another Ag⋯O inter­action [2.899 (2) Å] and a C—H⋯O hydrogen bond connect the layers into a three-dimensional network.

Related literature

For general background on coordination polymers and open-framework materials, see: James (2003[James, S. L. (2003). Chem. Soc. Rev. 32, 276-288.]); Serre et al. (2004[Serre, C., Millange, F., Thouvenot, C., Gardant, N., Pelle, F. & Ferey, G. (2004). J. Mater. Chem. 14, 1540-1543.]); Yaghi et al. (1998[Yaghi, O. M., Li, H. L., Davis, C., Richardson, D. & Groy, T. L. (1998). Acc. Chem. Res. 31, 474-484.], 2003[Yaghi, O. M., O'Keeffe, M., Ockwig, N. W., Chae, H. K., Eddaoudi, M. & Kim, J. (2003). Nature (London), 423, 705-714.]). For related structures, see: Evans & Lin (2001[Evans, O. R. & Lin, W. B. (2001). Chem. Mater. 13, 3009-3017.]); Luo et al. (2004[Luo, J. H., Jiang, F. L., Wang, R. H., Han, L., Lin, Z. Z., Cao, R. & Hong, M. C. (2004). J. Mol. Struct. 707, 211-216.]).

[Scheme 1]

Experimental

Crystal data

  • [Ag(C6H5NO2)2]ClO4

  • Mr = 453.54

  • Monoclinic, P 21 /c

  • a = 8.0139 (4) Å

  • b = 26.3288 (15) Å

  • c = 7.6891 (4) Å

  • β = 110.728 (1)°

  • V = 1517.36 (14) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 1.55 mm−1

  • T = 273 (2) K

  • 0.29 × 0.25 × 0.21 mm
Data collection

  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.649, Tmax = 0.731

  • 7763 measured reflections

  • 2729 independent reflections

  • 2150 reflections with I > 2σ(I)

  • Rint = 0.029
Refinement

  • R[F2 > 2σ(F2)] = 0.043

  • wR(F2) = 0.123

  • S = 0.87

  • 2729 reflections

  • 219 parameters

  • H-atom parameters constrained

  • Δρmax = 1.26 e Å−3

  • Δρmin = −0.57 e Å−3

Table 1
Selected geometric parameters (Å, °)

Ag1—N1 2.178 (4)
Ag1—N2 2.185 (4)
N1—Ag1—N2 165.65 (15)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C1—H1⋯O5i 0.93 2.51 3.244 (8) 136
C4—H4⋯O7ii 0.93 2.52 3.266 (8) 139
C6—H6⋯O7 0.93 2.52 3.248 (8) 136
C7—H7⋯O8i 0.93 2.49 3.287 (9) 144
C12—H12⋯O7 0.93 2.38 3.228 (9) 152
O2—H2⋯O4iii 0.82 1.84 2.649 (5) 169
O3—H3⋯O1iv 0.82 1.87 2.689 (5) 175
Symmetry codes: (i) x-1, y, z; (ii) [x, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]; (iii) [-x, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iv) [-x, y-{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808044206/hy2176sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808044206/hy2176Isup2.hkl

checkCIF report


Comment top

The use of multifunctional organic linker molecules in the preparation of coordination polymers and open-framework materials has led to the development of a rich field of chemistry owing to the potential applications of these materials in catalysis, separation, gas storage and molecular recognition (James, 2003; Serre et al., 2004; Yaghi et al., 1998, 2003). In our investigations we used nicotinic acid ligands for the preparation of new coordination polymers, because it can act as a multidentate ligand with versatile binding and coordination modes (Evans & Lin, 2001; Luo et al., 2004). In this paper, we report the crystal structure of the title compound, a new AgI complex obtained by the reaction of nicotinic acid, AgNO3 and perchloric acid in water.

As shown in Fig. 1, the title compound consists of a [Ag(C6H5NO2)2]+ cation and a perchlorate anion. The AgI atom exhibits a linear coordination geometry, defined by two N atoms from two pyridine-3-carboxylic acid ligands (Table 1). The complex cations are linked by hydrogen bonds between the carboxyl groups into a chain (Table 2). The chains are further connected by C—H···O hydrogen bonds involving C1, C6, C7 and C12 atoms and the perchlorate anions, and by a weak Ag1···O5(x-1, y, z) interaction [2.757 (8) Å] into a layer (Fig. 2). Another Ag1···O1(x, 3/2-y, z-1/2) interaction [2.899 (2) Å] and a C4—H4···O7(x, 3/2-y, 1/2+z) hydrogen bond connect the layers into a three-dimensional network.

Related literature top

For general background on coordination polymers and open-framework materials, see: James (2003); Serre et al. (2004); Yaghi et al. (1998, 2003). For related structures, see: Evans & Lin (2001); Luo et al. (2004).

Experimental top

A mixture of AgNO3 (0.169 g, 1 mmol), perchloric acid (0.12 ml), nicotinic acid (0.123 g, 1 mmol) and H2O (10 ml) was placed in a 23 ml Teflon-lined reactor, which was heated to 433 K for 3 d and then cooled to room temperature at a rate of 10 K h-1. The crystals obtained were washed with water and dried in air.

Refinement top

H atoms on C atoms were positioned geometrically and refined as riding atoms, with C—H = 0.93 Å and Uiso(H) = 1.2Ueq(C). H atoms on O atoms were located in difference Fourier maps and were fixed with O—H = 0.82 Å and Uiso(H) = 1.5Ueq(O). The highest residual electron density was found 1.31 Å from atom O7 and the deepest hole 0.46 Å from atom O7.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The structure of the title compound. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. The layer in the title compound. Hydrogen bonds and weak Ag···O interactions are shown as dashed lines.
Bis(pyridine-3-carboxylic acid-κN)silver(I) perchlorate top
Crystal data top
[Ag(C6H5NO2)2]ClO4F(000) = 896
Mr = 453.54Dx = 1.985 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 5837 reflections
a = 8.0139 (4) Åθ = 2.8–27.9°
b = 26.3288 (15) ŵ = 1.55 mm−1
c = 7.6891 (4) ÅT = 273 K
β = 110.728 (1)°Block, colourless
V = 1517.36 (14) Å30.29 × 0.25 × 0.21 mm
Z = 4
Data collection top
Bruker APEXII CCD
diffractometer		2729 independent reflections
Radiation source: fine-focus sealed tube2150 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.029
ϕ and ω scansθmax = 25.2°, θmin = 1.6°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −8→9
Tmin = 0.649, Tmax = 0.731k = −29→31
7763 measured reflectionsl = −9→8
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.043Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.123H-atom parameters constrained
S = 0.87 w = 1/[σ2(Fo2) + (0.0736P)2 + 4.5241P]
where P = (Fo2 + 2Fc2)/3
2729 reflections(Δ/σ)max = 0.001
219 parametersΔρmax = 1.26 e Å−3
0 restraintsΔρmin = −0.57 e Å−3
Crystal data top
[Ag(C6H5NO2)2]ClO4V = 1517.36 (14) Å3
Mr = 453.54Z = 4
Monoclinic, P21/cMo Kα radiation
a = 8.0139 (4) ŵ = 1.55 mm−1
b = 26.3288 (15) ÅT = 273 K
c = 7.6891 (4) Å0.29 × 0.25 × 0.21 mm
β = 110.728 (1)°
Data collection top
Bruker APEXII CCD
diffractometer		2729 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		2150 reflections with I > 2σ(I)
Tmin = 0.649, Tmax = 0.731Rint = 0.029
7763 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0430 restraints
wR(F2) = 0.123H-atom parameters constrained
S = 0.87Δρmax = 1.26 e Å−3
2729 reflectionsΔρmin = −0.57 e Å−3
219 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Ag10.40344 (6)0.612387 (13)0.34075 (6)0.05534 (19)
C10.3293 (6)0.72596 (17)0.4083 (7)0.0438 (11)
H10.21150.71500.36910.053*
Cl10.97387 (18)0.61558 (5)0.3633 (2)0.0544 (3)
N10.4208 (5)0.53278 (14)0.2719 (6)0.0457 (9)
O10.2535 (4)0.86018 (12)0.4508 (5)0.0488 (8)
C20.3650 (6)0.77700 (16)0.4460 (6)0.0367 (10)
N20.4580 (5)0.69166 (14)0.4261 (6)0.0437 (9)
O20.0616 (5)0.79535 (13)0.3776 (6)0.0596 (10)
H2−0.01200.81840.34990.089*
C30.2204 (6)0.81428 (17)0.4237 (7)0.0425 (11)
O30.0023 (4)0.43163 (13)0.1274 (6)0.0541 (9)
H3−0.07380.40930.09820.081*
C40.5421 (6)0.79317 (18)0.5073 (7)0.0466 (11)
H40.57060.82710.53560.056*
O40.1889 (5)0.36546 (12)0.1767 (5)0.0519 (9)
C50.6742 (6)0.75790 (19)0.5251 (7)0.0488 (12)
H50.79320.76780.56420.059*
O51.0454 (10)0.6352 (3)0.2338 (8)0.147 (3)
C60.6276 (6)0.70794 (18)0.4842 (7)0.0455 (11)
H60.71760.68430.49740.055*
O61.0605 (13)0.6412 (4)0.5267 (9)0.174 (4)
C70.2868 (6)0.49924 (17)0.2338 (7)0.0409 (10)
H70.17450.51070.22560.049*
O70.7884 (7)0.6209 (2)0.2885 (11)0.117 (2)
C80.3093 (6)0.44812 (16)0.2063 (6)0.0372 (10)
O81.0104 (10)0.5643 (3)0.3779 (16)0.187 (4)
C90.1598 (6)0.41126 (17)0.1687 (7)0.0409 (10)
C100.4758 (7)0.43088 (19)0.2185 (8)0.0500 (12)
H100.49480.39660.20250.060*
C110.6130 (7)0.4653 (2)0.2546 (8)0.0567 (14)
H110.72580.45470.26130.068*
C120.5813 (7)0.5153 (2)0.2807 (8)0.0534 (13)
H120.67510.53830.30560.064*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Ag10.0591 (3)0.0284 (2)0.0765 (3)0.00062 (16)0.0214 (2)−0.00512 (17)
C10.039 (2)0.035 (2)0.055 (3)−0.0009 (19)0.014 (2)−0.005 (2)
Cl10.0416 (7)0.0587 (8)0.0659 (8)0.0030 (6)0.0228 (6)0.0001 (6)
N10.044 (2)0.033 (2)0.060 (3)−0.0025 (17)0.0185 (19)−0.0041 (18)
O10.0469 (19)0.0275 (17)0.067 (2)−0.0023 (14)0.0137 (17)0.0003 (15)
C20.041 (2)0.030 (2)0.040 (2)−0.0015 (18)0.0161 (19)−0.0009 (18)
N20.044 (2)0.032 (2)0.054 (2)0.0018 (17)0.0163 (18)−0.0036 (17)
O20.043 (2)0.0321 (18)0.100 (3)0.0010 (15)0.020 (2)−0.0021 (18)
C30.044 (3)0.034 (2)0.050 (3)−0.003 (2)0.017 (2)−0.002 (2)
O30.0402 (19)0.0365 (18)0.084 (3)−0.0042 (15)0.0195 (18)−0.0055 (18)
C40.047 (3)0.035 (2)0.054 (3)−0.005 (2)0.014 (2)0.000 (2)
O40.049 (2)0.0302 (18)0.074 (2)0.0013 (15)0.0181 (17)0.0021 (16)
C50.038 (3)0.042 (3)0.065 (3)−0.002 (2)0.016 (2)−0.002 (2)
O50.133 (5)0.226 (9)0.086 (4)−0.095 (6)0.043 (4)−0.031 (5)
C60.042 (3)0.043 (3)0.051 (3)0.006 (2)0.016 (2)0.000 (2)
O60.219 (9)0.219 (9)0.081 (4)−0.109 (8)0.050 (5)−0.050 (5)
C70.036 (2)0.033 (2)0.051 (3)0.0015 (18)0.012 (2)−0.0008 (19)
O70.061 (3)0.086 (4)0.210 (7)0.007 (3)0.055 (4)0.005 (4)
C80.038 (2)0.032 (2)0.041 (2)0.0006 (18)0.0116 (19)−0.0027 (18)
O80.118 (6)0.104 (5)0.323 (12)0.054 (4)0.057 (7)−0.004 (7)
C90.042 (3)0.031 (2)0.047 (3)0.0009 (19)0.013 (2)−0.0031 (19)
C100.052 (3)0.034 (3)0.064 (3)0.004 (2)0.021 (2)−0.008 (2)
C110.044 (3)0.051 (3)0.079 (4)0.001 (2)0.027 (3)−0.010 (3)
C120.043 (3)0.045 (3)0.075 (4)−0.005 (2)0.024 (3)−0.004 (3)
Geometric parameters (Å, º) top
Ag1—N12.178 (4)O2—H20.8200
Ag1—N22.185 (4)O3—C91.303 (6)
Ag1—O1i2.899 (2)O3—H30.8200
Ag1—O5ii2.757 (8)C4—C51.378 (7)
C1—N21.341 (6)C4—H40.9300
C1—C21.383 (6)O4—C91.226 (6)
C1—H10.9300C5—C61.373 (7)
Cl1—O81.378 (7)C5—H50.9300
Cl1—O61.378 (6)C6—H60.9300
Cl1—O71.398 (6)C7—C81.384 (6)
Cl1—O51.411 (6)C7—H70.9300
N1—C71.341 (6)C8—C101.381 (7)
N1—C121.345 (6)C8—C91.489 (6)
O1—C31.239 (5)C10—C111.375 (7)
C2—C41.394 (6)C10—H100.9300
C2—C31.482 (6)C11—C121.370 (7)
N2—C61.342 (6)C11—H110.9300
O2—C31.294 (6)C12—H120.9300
N1—Ag1—N2165.65 (15)C2—C4—H4120.6
N2—C1—C2122.6 (4)C6—C5—C4119.1 (5)
N2—C1—H1118.7C6—C5—H5120.5
C2—C1—H1118.7C4—C5—H5120.5
O8—Cl1—O6112.4 (6)N2—C6—C5122.9 (4)
O8—Cl1—O7107.2 (4)N2—C6—H6118.5
O6—Cl1—O7116.4 (6)C5—C6—H6118.5
O8—Cl1—O5106.8 (6)N1—C7—C8122.4 (4)
O6—Cl1—O5105.3 (4)N1—C7—H7118.8
O7—Cl1—O5108.1 (5)C8—C7—H7118.8
C7—N1—C12117.6 (4)C10—C8—C7119.0 (4)
C7—N1—Ag1124.9 (3)C10—C8—C9119.4 (4)
C12—N1—Ag1117.3 (3)C7—C8—C9121.6 (4)
C1—C2—C4118.5 (4)O4—C9—O3124.6 (4)
C1—C2—C3121.6 (4)O4—C9—C8120.4 (4)
C4—C2—C3119.9 (4)O3—C9—C8115.0 (4)
C1—N2—C6118.1 (4)C11—C10—C8118.8 (5)
C1—N2—Ag1123.2 (3)C11—C10—H10120.6
C6—N2—Ag1118.5 (3)C8—C10—H10120.6
C3—O2—H2109.5C12—C11—C10119.1 (5)
O1—C3—O2123.6 (4)C12—C11—H11120.4
O1—C3—C2120.9 (4)C10—C11—H11120.4
O2—C3—C2115.4 (4)N1—C12—C11123.0 (5)
C9—O3—H3109.5N1—C12—H12118.5
C5—C4—C2118.8 (4)C11—C12—H12118.5
C5—C4—H4120.6
Symmetry codes: (i) x, −y+3/2, z−1/2; (ii) x−1, y, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1···O5ii0.932.513.244 (8)136
C4—H4···O7iii0.932.523.266 (8)139
C6—H6···O70.932.523.248 (8)136
C7—H7···O8ii0.932.493.287 (9)144
C12—H12···O70.932.383.228 (9)152
O2—H2···O4iv0.821.842.649 (5)169
O3—H3···O1v0.821.872.689 (5)175
Symmetry codes: (ii) x−1, y, z; (iii) x, −y+3/2, z+1/2; (iv) −x, y+1/2, −z+1/2; (v) −x, y−1/2, −z+1/2.

Experimental details

Crystal data
Chemical formula[Ag(C6H5NO2)2]ClO4
Mr453.54
Crystal system, space groupMonoclinic, P21/c
Temperature (K)273
a, b, c (Å)8.0139 (4), 26.3288 (15), 7.6891 (4)
β (°) 110.728 (1)
V (Å3)1517.36 (14)
Z4
Radiation typeMo Kα
µ (mm−1)1.55
Crystal size (mm)0.29 × 0.25 × 0.21
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.649, 0.731
No. of measured, independent and
observed [I > 2σ(I)] reflections		7763, 2729, 2150
Rint0.029
(sin θ/λ)max (Å−1)0.599
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.043, 0.123, 0.87
No. of reflections2729
No. of parameters219
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)1.26, −0.57

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Selected geometric parameters (Å, º) top
Ag1—N12.178 (4)Ag1—N22.185 (4)
N1—Ag1—N2165.65 (15)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1···O5i0.932.513.244 (8)136
C4—H4···O7ii0.932.523.266 (8)139
C6—H6···O70.932.523.248 (8)136
C7—H7···O8i0.932.493.287 (9)144
C12—H12···O70.932.383.228 (9)152
O2—H2···O4iii0.821.842.649 (5)169
O3—H3···O1iv0.821.872.689 (5)175
Symmetry codes: (i) x−1, y, z; (ii) x, −y+3/2, z+1/2; (iii) −x, y+1/2, −z+1/2; (iv) −x, y−1/2, −z+1/2.
 

Acknowledgements

The authors kindly acknowledge Bijie University for supporting this work.

References

First citationBruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
 First citationEvans, O. R. & Lin, W. B. (2001). Chem. Mater. 13, 3009–3017.  Web of Science CSD CrossRef CAS Google Scholar
 First citationJames, S. L. (2003). Chem. Soc. Rev. 32, 276–288.  Web of Science CrossRef PubMed CAS Google Scholar
 First citationLuo, J. H., Jiang, F. L., Wang, R. H., Han, L., Lin, Z. Z., Cao, R. & Hong, M. C. (2004). J. Mol. Struct. 707, 211–216.  Web of Science CSD CrossRef CAS Google Scholar
 First citationSerre, C., Millange, F., Thouvenot, C., Gardant, N., Pelle, F. & Ferey, G. (2004). J. Mater. Chem. 14, 1540–1543.  Web of Science CSD CrossRef CAS Google Scholar
 First citationSheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.  Google Scholar
 First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationYaghi, O. M., Li, H. L., Davis, C., Richardson, D. & Groy, T. L. (1998). Acc. Chem. Res. 31, 474–484.  Web of Science CrossRef CAS Google Scholar
 First citationYaghi, O. M., O'Keeffe, M., Ockwig, N. W., Chae, H. K., Eddaoudi, M. & Kim, J. (2003). Nature (London), 423, 705–714.  Web of Science CrossRef PubMed CAS Google Scholar

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Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 65| Part 2| February 2009| Page m148
doi:10.1107/S1600536808044206
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