Redetermination of catena-Poly­[[(4-methyl­pyridine-κN)silver(I)]-μ₃-bromo]

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.

Key indicators

• Single-crystal X-ray study
• T = 170 K
• Mean [sigma](C-C) = 0.006 Å
• R factor = 0.032
• wR factor = 0.078
• Data-to-parameter ratio = 21.2

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT029_ALERT_3_B _diffrn_measured_fraction_theta_full Low .......       0.94

Alert level C
REFLT03_ALERT_3_C  Reflection count < 95% complete
           From the CIF: _diffrn_reflns_theta_max           27.98
           From the CIF: _diffrn_reflns_theta_full           0.00
           From the CIF: _reflns_number_total               3523
           TEST2: Reflns within _diffrn_reflns_theta_max
           Count of symmetry unique reflns         3737
           Completeness (_total/calc)             94.27%
PLAT041_ALERT_1_C Calc. and Rep. SumFormula Strings    Differ ....          ?
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT045_ALERT_1_C Calculated and Reported Z Differ by ............       0.50 Ratio
PLAT764_ALERT_4_C Overcomplete CIF Bond List Detected (Rep/Expd) .       1.12 Ratio

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

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

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Computing details

Data collection: IPDS Program Package (Stoe & Cie, 1998); cell refinement: IPDS Program Package; data reduction: IPDS Program Package; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997; program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP in SHELXTL (Bruker, 1998); software used to prepare material for publication: CIFTAB in SHELXTL.

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

Crystal data

[AgBr(C6H7N)]	F(000) = 1056
Mr = 280.91	Dx = 2.400 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 7718 reflections
a = 8.8523 (6) Å	θ = 2.5–28°
b = 17.8849 (10) Å	µ = 7.64 mm^−1
c = 9.9601 (7) Å	T = 170 K
β = 99.550 (8)°	Block, colourless
V = 1555.05 (17) Å^3	0.11 × 0.09 × 0.09 mm
Z = 8

Data collection

Stoe IPDS diffractometer	3523 independent reflections
Radiation source: fine-focus sealed tube	2208 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.046
φ scans	θmax = 28.0°, θmin = 2.6°
Absorption correction: numerical (X-SHAPE; Stoe & Cie, 1998)	h = −11→11
Tmin = 0.444, Tmax = 0.502	k = −23→23
13360 measured reflections	l = −13→13

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.032	H-atom parameters constrained
wR(F^2) = 0.078	w = 1/[σ^2(Fo^2) + (0.0395P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 0.93	(Δ/σ)max = 0.001
3523 reflections	Δρmax = 0.61 e Å^−3
166 parameters	Δρmin = −0.69 e Å^−3
0 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.00093 (17)

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
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*
H16C	0.9892	0.2756	1.1446	0.058*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
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—Br2^i	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—Ag1^i	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—Br1^ii	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—Ag2^ii	3.1982 (9)	C12—C13	1.390 (6)
Br1—Ag2^ii	2.6654 (7)	C12—H12	0.9500
Br2—Ag1^i	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—Br2^i	120.68 (10)	C3—C2—C1	119.9 (5)
N1—Ag1—Br1	102.63 (11)	C3—C2—H2	120.0
Br2^i—Ag1—Br1	113.166 (18)	C1—C2—H2	120.0
N1—Ag1—Br2	94.61 (9)	C2—C3—C4	117.5 (4)
Br2^i—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—Ag1^i	120.83 (10)	C3—C4—C5	119.2 (4)
Br2^i—Ag1—Ag1^i	58.891 (18)	C3—C4—H4	120.4
Br1—Ag1—Ag1^i	133.65 (2)	C5—C4—H4	120.4
Br2—Ag1—Ag1^i	52.920 (16)	N1—C5—C4	122.8 (5)
N1—Ag1—Ag2	108.33 (10)	N1—C5—H5	118.6
Br2^i—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
Ag1^i—Ag1—Ag2	91.131 (18)	H6A—C6—H6B	109.5
N11—Ag2—Br1^ii	124.10 (10)	C3—C6—H6C	109.5
N11—Ag2—Br2	104.56 (10)	H6A—C6—H6C	109.5
Br1^ii—Ag2—Br2	108.030 (18)	H6B—C6—H6C	109.5
N11—Ag2—Br1	98.36 (9)	C11—N11—C15	116.5 (4)
Br1^ii—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)
Br1^ii—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—Ag2^ii	126.68 (10)	C13—C12—H12	119.9
Br1^ii—Ag2—Ag2^ii	57.575 (17)	C11—C12—H12	119.9
Br2—Ag2—Ag2^ii	126.43 (2)	C14—C13—C12	116.3 (4)
Br1—Ag2—Ag2^ii	51.822 (16)	C14—C13—C16	121.7 (5)
Ag1—Ag2—Ag2^ii	89.461 (18)	C12—C13—C16	122.0 (4)
Ag2^ii—Br1—Ag1	110.57 (2)	C15—C14—C13	120.4 (4)
Ag2^ii—Br1—Ag2	70.603 (19)	C15—C14—H14	119.8
Ag1—Br1—Ag2	67.427 (16)	C13—C14—H14	119.8
Ag1^i—Br2—Ag2	110.69 (2)	N11—C15—C14	123.0 (4)
Ag1^i—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

Symmetry codes: (i) −x+2, −y+1, −z+1; (ii) −x+1, −y+1, −z+1.