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metal-organic papers

m1608

NaÈther and Beck [AgBr(C6H7N)] doi: 10.1107/S1600536804025139 Acta Cryst.(2004). E60, m1608±m1610 Acta Crystallographica Section E

Structure Reports Online

ISSN 1600-5368

Redetermination of

catena

-Poly[[(4-methyl-pyridine-

j

N

)silver(I)]-

l

3

-bromo]

Christian NaÈther* and Andreas Beck

Institut fuÈr Anorganische Chemie, Christian-Albrechts-UniversitaÈt Kiel, Olshausenstraûe 40, D-24098 Kiel, Germany

Correspondence e-mail: cnaether@ac.uni-kiel.de

Key indicators

Single-crystal X-ray study

T= 170 K

Mean(C±C) = 0.006 AÊ

Rfactor = 0.032

wRfactor = 0.078

Data-to-parameter ratio = 21.2

For details of how these key indicators were automatically derived from the article, see http://journals.iucr.org/e.

#2004 International Union of Crystallography Printed in Great Britain ± all rights reserved

In the crystal structure of the title compound, [AgBr(C6H7N)]n, the Ag and Br atoms form Ag±Br double chains in which each Ag atom is coordinated by three Br atoms and the N atom of a 4-methylpyridine ligand in a distorted tetrahedral geometry. The asymmetric unit contains two Ag atoms, two Br atoms, and two 4-methylpyridine ligands.

Comment

The structure determination of the title compound, (I), was undertaken as part of a project on the synthesis, structure and reactivity of coordination polymers based on silver(I) halides and nitrogen-donor ligands. The structure of (I) had been determined previously by Healy et al. (1985) at room temperature in space group P21/n [a = 10.286 (5), b =

18.066 (9),c= 4.390 (3) AÊ, and= 104.31 (5)]. Healyet al.

(1985) pointed out that the 4-methylpyridine ligand is disor-dered and they assumed that the ligand oscillated about the NÐCÐC axis. We have performed a low-temperature deter-mination at 150 K and found a unit cell in which thecaxis is doubled. Re®nement has been carried out in space group

P21/n [a = 9.9601 (7) AÊ, b = 17.8849 (10) AÊ and c =

8.8523 (6) AÊ, and= 99.550 (8)].

In contrast to the room-temperature determination, at 150 K, the asymmetric unit consists of two crystallographically independent Ag and two Br atoms, as well as two crystal-lographically independent 4-methylpyridine ligands (Fig. 1). Each Ag atom is coordinated by three Br atoms and the N atom of a 4-methylpyridine ligand in a distorted tetrahedral

Received 4 October 2004 Accepted 5 October 2004 Online 9 October 2004

Figure 1

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geometry. The Ag and Br atoms are connected into Ag±Br double chains which are elongated in the direction of the a

axis (Figs. 2 and 3). In contrast to the structure determined by Healyet al., we found no disorder of the ligand. In addition, we have re®ned the structure using low-temperature data in the small unit cell with halvedcaxis. In this case, the asymmetric unit consists of one crystallographically independent Ag and Br atom and one independent ligand which is disordered. The structure can be re®ned successfully using a split model and assuming a disorder in which the phenyl ring exhibits two different orientations about the NÐCÐC axis. Because of the different temperatures of the previous and the present investigation, we cannot exclude that, for example, a low-temperature phase transition occurred. If our crystals are investigated at room temperature they immediately decom-pose completely. This was not the case for the previous determination because the crystals were sealed together with mother liquor into a capillary tube.

Experimental

AgBr (239.12 mg, 1.28 mmol) was reacted with 4-methylpyridine (2.0 ml, 20.0 mmol) in a glass container at room temperature in the dark. After 7 d, colourless crystals suitable for X-ray structure analysis were obtained. A large amount of a crystalline powder was obtained by the reaction of AgBr (240.70 mg, 1.28 mmol) in 4-methylpyridine (2.0 ml, 20.0 mmol) at room temperature with stirring for 3 d. The product was washed with diethyl ether and ®ltered off [yield (based on AgBr) 53.3%]. Elemental analysis calculated: C 25.7, H 2.5, N 5.0%; found: C 26.1, H 2.6, N 5.1%.

Crystal data

[AgBr(C6H7N)]

Mr= 280.91 Monoclinic,P21=n

a= 8.8523 (6) AÊ

b= 17.8849 (10) AÊ

c= 9.9601 (7) AÊ = 99.550 (8) V= 1555.05 (17) AÊ3

Z= 8

Dx= 2.400 Mg mÿ3 MoKradiation Cell parameters from 7718

re¯ections = 2.5±28

= 7.64 mmÿ1

T= 170 (2) K Block, colourless 0.110.090.09 mm

Data collection

Stoe IPDS diffractometer 'scans

Absorption correction: numerical (X-SHAPE; Stoe & Cie, 1998)

Tmin= 0.444,Tmax= 0.502 13360 measured re¯ections 3523 independent re¯ections

2208 re¯ections withI> 2(I)

Rint= 0.046

max= 28.0

h=ÿ11!11

k=ÿ23!23

l=ÿ13!13

Refinement

Re®nement onF2

R[F2> 2(F2)] = 0.032

wR(F2) = 0.078

S= 0.93 3523 re¯ections 166 parameters

H-atom parameters constrained

w= 1/[2(F

o2) + (0.0395P)2] whereP= (Fo2+ 2Fc2)/3 (/)max= 0.001

max= 0.61 e AÊÿ3

min=ÿ0.69 e AÊÿ3

Extinction correction:SHELXL97 Extinction coef®cient: 0.00093 (17)

Table 1

Selected geometric parameters (AÊ,).

Ag1ÐN1 2.307 (4)

Ag1ÐBr2i 2.6460 (7)

Ag1ÐBr1 2.7340 (7)

Ag1ÐBr2 2.8397 (6)

Ag1ÐAg1i 3.0792 (8)

Ag1ÐAg2 3.1078 (6)

Ag2ÐN11 2.302 (4)

Ag2ÐBr1ii 2.6654 (7)

Ag2ÐBr2 2.7245 (7)

Ag2ÐBr1 2.8620 (6)

Ag2ÐAg2ii 3.1982 (9)

N1ÐAg1ÐBr2i 120.68 (10)

N1ÐAg1ÐBr1 102.63 (11)

Br2iÐAg1ÐBr1 113.166 (18)

N1ÐAg1ÐBr2 94.61 (9)

Br2iÐAg1ÐBr2 111.811 (19)

Br1ÐAg1ÐBr2 112.45 (2)

N1ÐAg1ÐAg1i 120.83 (10) Br2iÐAg1ÐAg1i 58.891 (18) Br1ÐAg1ÐAg1i 133.65 (2) Br2ÐAg1ÐAg1i 52.920 (16)

N1ÐAg1ÐAg2 108.33 (10)

Br2iÐAg1ÐAg2 130.481 (17)

Br1ÐAg1ÐAg2 58.250 (15)

Br2ÐAg1ÐAg2 54.302 (15)

Ag1iÐAg1ÐAg2 91.131 (18) N11ÐAg2ÐBr1ii 124.10 (10) N11ÐAg2ÐBr2 104.56 (10) Br1iiÐAg2ÐBr2 108.030 (18)

N11ÐAg2ÐBr1 98.36 (9)

Br1iiÐAg2ÐBr1 109.397 (19)

Br2ÐAg2ÐBr1 112.05 (2)

N11ÐAg2ÐAg1 107.76 (10)

Br1iiÐAg2ÐAg1 127.949 (17)

Br2ÐAg2ÐAg1 57.825 (14)

Br1ÐAg2ÐAg1 54.323 (15)

N11ÐAg2ÐAg2ii 126.68 (10) Br1iiÐAg2ÐAg2ii 57.575 (17) Br2ÐAg2ÐAg2ii 126.43 (2) Br1ÐAg2ÐAg2ii 51.822 (16) Ag1ÐAg2ÐAg2ii 89.461 (18) Ag2iiÐBr1ÐAg1 110.57 (2) Ag2iiÐBr1ÐAg2 70.603 (19)

Ag1ÐBr1ÐAg2 67.427 (16)

Ag1iÐBr2ÐAg2 110.69 (2) Ag1iÐBr2ÐAg1 68.189 (19)

Ag2ÐBr2ÐAg1 67.873 (17)

Symmetry codes: (i) 2ÿx;1ÿy;1ÿz; (ii) 1ÿx;1ÿy;1ÿz.

metal-organic papers

Acta Cryst.(2004). E60, m1608±m1610 NaÈther and Beck [AgBr(C6H7N)]

m1609

Figure 2

The crystal structure of the title compound, viewed along the baxis,

showing the Ag±Br double chains. Figure 3

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The aromatic H atoms were positioned with idealized geometry (CÐH) = 0.93 AÊ) and re®ned with ®xed isotropic displacement parameters [Uiso(H) = 1.2Ueq(C)] using the riding model. The

posi-tions of the methyl H atoms were idealized (CÐH = 0.98 AÊ), then re®ned with ®xed isotropic displacement parameters [Uiso(H) =

1.5Ueq(C)] as rigid groups allowed to rotate but not tip.

Data collection:IPDSProgram Package (Stoe & Cie, 1998); cell re®nement:IPDSProgram Package; data reduction:IPDSProgram Package; program(s) used to solve structure:SHELXS97 (Sheldrick, 1997; program(s) used to re®ne structure: SHELXL97 (Sheldrick, 1997); molecular graphics:XPinSHELXTL(Bruker, 1998); software used to prepare material for publication:XCIFinSHELXTL.

This work is supported by the state of Schleswig-Holstein. We are grateful to Professor Dr Wolfgang Bensch for ®nancial support and the facility to use his experimental equipment.

References

Bruker (1998). SHELXTL. Version 5.1. Bruker AXS Inc., Madison, Wisconsin, USA.

Healy, P. C., Mills, N. K. & White, A. H. (1985).J. Chem. Soc. Dalton Trans.pp. 111±116.

Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of GoÈttingen, Germany.

Stoe & Cie (1998).X-SHAPE(Version 1.03) andIPDSprogram package (Version 2.89). Stoe & Cie, Darmstadt, Germany.

metal-organic papers

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supporting information

sup-1

Acta Cryst. (2004). E60, m1608–m1610

supporting information

Acta Cryst. (2004). E60, m1608–m1610 [https://doi.org/10.1107/S1600536804025139]

Redetermination of

catena

-Poly[[(4-methylpyridine-

κ

N

)silver(I)]-

µ

3

-bromo]

Christian N

ä

ther and Andreas Beck

catena-Poly[[(4-methylpyridine-κN)silver(I)]-µ3bromo]

Crystal data [AgBr(C6H7N)]

Mr = 280.91

Monoclinic, P21/n

Hall symbol: -P 2yn a = 8.8523 (6) Å b = 17.8849 (10) Å c = 9.9601 (7) Å β = 99.550 (8)° V = 1555.05 (17) Å3

Z = 8

F(000) = 1056 Dx = 2.400 Mg m−3

Mo radiation, λ = 0.71073 Å Cell parameters from 7718 reflections θ = 2.5–28°

µ = 7.64 mm−1

T = 170 K Block, colourless 0.11 × 0.09 × 0.09 mm

Data collection Stoe IPDS

diffractometer

Radiation source: fine-focus sealed tube Graphite monochromator

φ scans

Absorption correction: numerical (X-SHAPE; Stoe & Cie, 1998) Tmin = 0.444, Tmax = 0.502

13360 measured reflections 3523 independent reflections 2208 reflections with I > 2σ(I) Rint = 0.046

θmax = 28.0°, θmin = 2.6°

h = −11→11 k = −23→23 l = −13→13

Refinement Refinement on F2

Least-squares matrix: full R[F2 > 2σ(F2)] = 0.032

wR(F2) = 0.078

S = 0.93 3523 reflections 166 parameters 0 restraints

Primary atom site location: structure-invariant direct methods

Secondary atom site location: difference Fourier map

Hydrogen site location: inferred from neighbouring sites

H-atom parameters constrained w = 1/[σ2(F

o2) + (0.0395P)2]

where P = (Fo2 + 2Fc2)/3

(Δ/σ)max = 0.001

Δρmax = 0.61 e Å−3

Δρmin = −0.69 e Å−3

Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4

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supporting information

sup-2

Acta Cryst. (2004). E60, m1608–m1610 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 (Å2)

x y z Uiso*/Ueq

Ag1 0.85489 (5) 0.48457 (2) 0.39523 (4) 0.03276 (13)

Ag2 0.64810 (5) 0.51009 (2) 0.61457 (4) 0.03233 (12)

Br1 0.59663 (6) 0.40156 (3) 0.40068 (5) 0.02656 (13)

Br2 0.89576 (6) 0.59790 (3) 0.59770 (5) 0.02666 (13)

N1 0.7784 (5) 0.5661 (2) 0.2175 (4) 0.0238 (8)

C1 0.6405 (6) 0.5578 (2) 0.1390 (5) 0.0256 (9)

H1 0.5816 0.5147 0.1512 0.031*

C2 0.5806 (6) 0.6099 (2) 0.0403 (4) 0.0247 (9)

H2 0.4836 0.6015 −0.0145 0.030*

C3 0.6626 (6) 0.6741 (3) 0.0224 (4) 0.0247 (10)

C4 0.8053 (6) 0.6830 (3) 0.1042 (5) 0.0285 (10)

H4 0.8654 0.7261 0.0954 0.034*

C5 0.8590 (6) 0.6273 (3) 0.1998 (5) 0.0268 (10)

H5 0.9570 0.6335 0.2542 0.032*

C6 0.5975 (7) 0.7327 (3) −0.0802 (5) 0.0391 (14)

H6A 0.4984 0.7498 −0.0602 0.059*

H6B 0.5834 0.7112 −0.1719 0.059*

H6C 0.6682 0.7751 −0.0751 0.059*

N11 0.7301 (5) 0.4303 (2) 0.7932 (4) 0.0224 (8)

C11 0.7008 (6) 0.3573 (2) 0.7799 (4) 0.0241 (10)

H11 0.6448 0.3399 0.6961 0.029*

C12 0.7476 (6) 0.3053 (2) 0.8821 (4) 0.0250 (10)

H12 0.7255 0.2538 0.8662 0.030*

C13 0.8269 (6) 0.3284 (3) 1.0075 (5) 0.0257 (10)

C14 0.8568 (6) 0.4045 (2) 1.0217 (4) 0.0240 (9)

H14 0.9107 0.4233 1.1053 0.029*

C15 0.8087 (5) 0.4531 (2) 0.9148 (4) 0.0215 (9)

H15 0.8318 0.5047 0.9273 0.026*

C16 0.8773 (7) 0.2746 (3) 1.1210 (5) 0.0389 (13)

H16A 0.8436 0.2241 1.0921 0.058*

H16B 0.8321 0.2890 1.2006 0.058*

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supporting information

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Acta Cryst. (2004). E60, m1608–m1610 Atomic displacement parameters (Å2)

U11 U22 U33 U12 U13 U23

Ag1 0.0301 (3) 0.0326 (2) 0.0324 (2) 0.00621 (17) −0.00425 (17) 0.00059 (15)

Ag2 0.0326 (3) 0.0283 (2) 0.0347 (2) 0.00393 (17) 0.00147 (17) 0.00641 (14)

Br1 0.0248 (3) 0.0218 (2) 0.0311 (2) 0.00221 (17) −0.0012 (2) −0.00182 (17)

Br2 0.0222 (3) 0.0217 (2) 0.0343 (3) 0.00100 (17) −0.0004 (2) −0.00518 (17)

N1 0.021 (2) 0.0229 (19) 0.0256 (19) 0.0008 (16) −0.0004 (16) −0.0018 (14)

C1 0.021 (3) 0.025 (2) 0.030 (2) 0.0006 (18) 0.0001 (19) −0.0004 (17)

C2 0.023 (3) 0.024 (2) 0.026 (2) 0.0026 (17) −0.0005 (18) −0.0034 (16)

C3 0.025 (3) 0.027 (2) 0.023 (2) 0.0029 (18) 0.0074 (18) 0.0019 (16)

C4 0.023 (3) 0.028 (2) 0.035 (2) −0.0063 (19) 0.006 (2) −0.0014 (18)

C5 0.018 (3) 0.032 (2) 0.028 (2) −0.0022 (19) −0.0013 (19) −0.0048 (18)

C6 0.045 (4) 0.031 (3) 0.040 (3) −0.003 (2) 0.004 (3) 0.014 (2)

N11 0.023 (2) 0.0226 (18) 0.0218 (17) 0.0011 (16) 0.0046 (16) 0.0029 (14)

C11 0.028 (3) 0.021 (2) 0.022 (2) −0.0027 (18) 0.0011 (18) −0.0033 (15)

C12 0.027 (3) 0.018 (2) 0.029 (2) 0.0001 (17) 0.0030 (19) 0.0035 (16)

C13 0.020 (3) 0.029 (2) 0.028 (2) 0.0022 (19) 0.0029 (19) 0.0042 (17)

C14 0.023 (3) 0.026 (2) 0.0221 (19) −0.0037 (17) 0.0026 (18) −0.0019 (16)

C15 0.020 (3) 0.0203 (19) 0.0239 (19) −0.0028 (15) 0.0012 (17) −0.0058 (15)

C16 0.043 (4) 0.037 (3) 0.032 (3) 0.000 (2) −0.008 (2) 0.011 (2)

Geometric parameters (Å, º)

Ag1—N1 2.307 (4) C4—C5 1.405 (7)

Ag1—Br2i 2.6460 (7) C4—H4 0.9500

Ag1—Br1 2.7340 (7) C5—H5 0.9500

Ag1—Br2 2.8397 (6) C6—H6A 0.9800

Ag1—Ag1i 3.0792 (8) C6—H6B 0.9800

Ag1—Ag2 3.1078 (6) C6—H6C 0.9800

Ag2—N11 2.302 (4) N11—C11 1.332 (6)

Ag2—Br1ii 2.6654 (7) N11—C15 1.356 (6)

Ag2—Br2 2.7245 (7) C11—C12 1.391 (6)

Ag2—Br1 2.8620 (6) C11—H11 0.9500

Ag2—Ag2ii 3.1982 (9) C12—C13 1.390 (6)

Br1—Ag2ii 2.6654 (7) C12—H12 0.9500

Br2—Ag1i 2.6460 (7) C13—C14 1.389 (6)

N1—C5 1.334 (6) C13—C16 1.495 (7)

N1—C1 1.344 (6) C14—C15 1.385 (6)

C1—C2 1.395 (6) C14—H14 0.9500

C1—H1 0.9500 C15—H15 0.9500

C2—C3 1.386 (7) C16—H16A 0.9800

C2—H2 0.9500 C16—H16B 0.9800

C3—C4 1.394 (7) C16—H16C 0.9800

C3—C6 1.509 (7)

N1—Ag1—Br2i 120.68 (10) C3—C2—C1 119.9 (5)

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supporting information

sup-4

Acta Cryst. (2004). E60, m1608–m1610

Br2i—Ag1—Br1 113.166 (18) C1—C2—H2 120.0

N1—Ag1—Br2 94.61 (9) C2—C3—C4 117.5 (4)

Br2i—Ag1—Br2 111.811 (19) C2—C3—C6 120.9 (5)

Br1—Ag1—Br2 112.45 (2) C4—C3—C6 121.6 (5)

N1—Ag1—Ag1i 120.83 (10) C3—C4—C5 119.2 (4)

Br2i—Ag1—Ag1i 58.891 (18) C3—C4—H4 120.4

Br1—Ag1—Ag1i 133.65 (2) C5—C4—H4 120.4

Br2—Ag1—Ag1i 52.920 (16) N1—C5—C4 122.8 (5)

N1—Ag1—Ag2 108.33 (10) N1—C5—H5 118.6

Br2i—Ag1—Ag2 130.481 (17) C4—C5—H5 118.6

Br1—Ag1—Ag2 58.250 (15) C3—C6—H6A 109.5

Br2—Ag1—Ag2 54.302 (15) C3—C6—H6B 109.5

Ag1i—Ag1—Ag2 91.131 (18) H6A—C6—H6B 109.5

N11—Ag2—Br1ii 124.10 (10) C3—C6—H6C 109.5

N11—Ag2—Br2 104.56 (10) H6A—C6—H6C 109.5

Br1ii—Ag2—Br2 108.030 (18) H6B—C6—H6C 109.5

N11—Ag2—Br1 98.36 (9) C11—N11—C15 116.5 (4)

Br1ii—Ag2—Br1 109.397 (19) C11—N11—Ag2 120.0 (3)

Br2—Ag2—Br1 112.05 (2) C15—N11—Ag2 123.6 (3)

N11—Ag2—Ag1 107.76 (10) N11—C11—C12 123.6 (4)

Br1ii—Ag2—Ag1 127.949 (17) N11—C11—H11 118.2

Br2—Ag2—Ag1 57.825 (14) C12—C11—H11 118.2

Br1—Ag2—Ag1 54.323 (15) C13—C12—C11 120.2 (4)

N11—Ag2—Ag2ii 126.68 (10) C13—C12—H12 119.9

Br1ii—Ag2—Ag2ii 57.575 (17) C11—C12—H12 119.9

Br2—Ag2—Ag2ii 126.43 (2) C14—C13—C12 116.3 (4)

Br1—Ag2—Ag2ii 51.822 (16) C14—C13—C16 121.7 (5)

Ag1—Ag2—Ag2ii 89.461 (18) C12—C13—C16 122.0 (4)

Ag2ii—Br1—Ag1 110.57 (2) C15—C14—C13 120.4 (4)

Ag2ii—Br1—Ag2 70.603 (19) C15—C14—H14 119.8

Ag1—Br1—Ag2 67.427 (16) C13—C14—H14 119.8

Ag1i—Br2—Ag2 110.69 (2) N11—C15—C14 123.0 (4)

Ag1i—Br2—Ag1 68.189 (19) N11—C15—H15 118.5

Ag2—Br2—Ag1 67.873 (17) C14—C15—H15 118.5

C5—N1—C1 118.0 (4) C13—C16—H16A 109.5

C5—N1—Ag1 121.6 (3) C13—C16—H16B 109.5

C1—N1—Ag1 119.9 (3) H16A—C16—H16B 109.5

N1—C1—C2 122.5 (4) C13—C16—H16C 109.5

N1—C1—H1 118.7 H16A—C16—H16C 109.5

C2—C1—H1 118.7 H16B—C16—H16C 109.5

References

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