metal-organic compounds
The crystal structure of the polymeric title complex, [CuBr2(C4H8N8)2]n, has been solved from X-ray powder data and refined with the Rietveld method using geometrical soft restraints. The Cu atom, lying on an inversion centre, has octahedral coordination, with two N atoms [Cu—N = 2.090 (13) Å] and two Br atoms [Cu—Br = 2.432 (4) Å] in the equatorial positions. The axial sites of the octahedron are occupied by two Br atoms, with Cu—Br distances of 3.101 (4) Å. Each Br atom is a bridge between neighbouring Cu atoms, which is responsible for formation of polymeric layers parallel to the bc plane, with only van der Waals interactions between them.
Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536805002205/dn6190sup1.cif | |
Rietveld powder data file (CIF format) https://doi.org/10.1107/S1600536805002205/dn6190Isup2.rtv |
CCDC reference: 263584
Computing details top
Data collection: local program; cell refinement: FULLPROF (Rodrigues-Carvajal, 2001); data reduction: local program; program(s) used to solve structure: EXPO (Altomare et al., 1999); program(s) used to refine structure: FULLPROF (Rodrigues-Carvajal, 2001); molecular graphics: ORTEP-3 for Windows (Farrugia, 1999) and PLATON (Spek, 2003); software used to prepare material for publication: FULLPROF.
Crystal data top
[CuBr2(C4H8N8)2] | Z = 2 |
Mr = 391.53 | Dx = 2.317 Mg m−3 |
Monoclinic, P21/c | Cu Kα radiation, λ = 1.5418 Å |
Hall symbol: -P 2ybc | T = 293 K |
a = 11.0319 (5) Å | Particle morphology: plate |
b = 6.8524 (4) Å | brown |
c = 7.7018 (4) Å | flat_sheet, 30 × 30 mm |
β = 105.444 (3)° | Specimen preparation: Prepared at 293 K |
V = 561.20 (5) Å3 |
Data collection top
HZG-4A (Carl Zeiss, Jena) diffractometer | Data collection mode: reflection |
Radiation source: fine-focus sealed X-ray tube, BSV-29 | Scan method: step |
Ni filtered monochromator | 2θmin = 5°, 2θmax = 110°, 2θstep = 0.02° |
Specimen mounting: packed powder pellet |
Refinement top
Refinement on Inet | 44 parameters |
Least-squares matrix: full with fixed elements per cycle | 17 restraints |
Rp = 0.054 | 0 constraints |
Rwp = 0.090 | H-atom parameters constrained |
Rexp = 0.073 | Weighting scheme based on measured s.u.'s |
RBragg = 0.049 | (Δ/σ)max = 0.016 |
5251 data points | Background function: polynomial |
Profile function: pseudo-Voight |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
x | y | z | Uiso*/Ueq | ||
Cu | 0.00000 | 0.00000 | 0.00000 | 0.034 (3)* | |
Br | 0.0933 (2) | 0.2051 (6) | 0.2589 (5) | 0.0173 (16)* | |
N1 | 0.3146 (9) | −0.3913 (13) | 0.115 (4) | 0.061 (5)* | |
N2 | 0.3542 (11) | −0.2229 (13) | 0.055 (3) | 0.061 (5)* | |
N3 | 0.2804 (9) | −0.0756 (14) | 0.035 (4) | 0.061 (5)* | |
N4 | 0.1702 (9) | −0.1519 (13) | 0.052 (4) | 0.061 (5)* | |
C5 | 0.1947 (9) | −0.3381 (15) | 0.077 (5) | 0.061 (5)* | |
C6 | 0.3781 (13) | −0.5829 (15) | 0.142 (4) | 0.061 (5)* | |
H5 | 0.1309 | −0.4294 | 0.0679 | 0.073* | |
H6A | 0.4673 | −0.5644 | 0.16740 | 0.092* | |
H6B | 0.3495 | −0.6602 | 0.0348 | 0.092* | |
H6C | 0.3587 | −0.6488 | 0.2412 | 0.092* |
Geometric parameters (Å, º) top
Cu—Br | 2.432 (4) | N3—N4 | 1.361 (18) |
Cu—Bri | 3.101 (4) | N4—C5 | 1.308 (15) |
Cu—N4 | 2.090 (13) | C5—H5 | 0.93 |
N1—N2 | 1.356 (18) | C6—H6A | 0.96 |
N1—C5 | 1.33 (2) | C6—H6B | 0.96 |
N1—C6 | 1.477 (16) | C6—H6C | 0.96 |
N2—N3 | 1.280 (16) | ||
N2—N1—C5 | 94.9 (17) | N1—C5—N4 | 117.1 (17) |
N2—N1—C6 | 128.4 (16) | N1—C6—H6A | 109.4 |
C5—N1—C6 | 133.0 (19) | N1—C6—H6B | 109.4 |
N1—N2—N3 | 117.3 (16) | N1—C6—H6C | 109.4 |
N2—N3—N4 | 104.0 (16) | N4—Cu—Br | 88.1 (7) |
Cu—N4—N3 | 124.7 (11) | N4—Cu—Bri | 89.1 (6) |
Cu—N4—C5 | 130.9 (12) | Br—Cu—Bri | 91.2 (2) |
N3—N4—C5 | 103.5 (15) |
Symmetry code: (i) −x, y−1/2, −z+1/2. |