research papers
Single crystals of the title compounds were prepared by solid–solid reaction using BaBr2 flux at 1373 K. The structures of these two new cobaltites were solved and refined. The two compounds are built from a close-packing of [BaO3] and [BaOBr] layers with stacking sequences (c′chhcc′)3 and (c′chhhcc′)2 for the 18R and 14H structures, respectively, which create Co3O12 trimers or Co4O15 tetramers of face-sharing octahedra connected at their extremities to isolated tetrahedra by corner-sharing. These new materials are strongly related to the 5H-Ba5Co5O14/12H-Ba0.9CoO2.6 and 10H-Ba5Co5ClO13/6H-Ba6Co6ClO16 materials, with the existence of common blocks. In Ba6Co5BrO14 and Ba7Co6BrO17, all the atoms in the vicinity of the [BaOBr] layers are disordered, whereas the rest of the structure is perfectly ordered.
Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108768107029394/bp5003sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108768107029394/bp5003Isup2.hkl | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108768107029394/bp5003IIsup3.hkl |
Computing details top
For both compounds, program(s) used to refine structure: (Jana2000; Petricek and Dusek, 2000); software used to prepare material for publication: (Jana2000; Petricek and Dusek, 2000).
(I) top
Crystal data top
Ba7BrCo6O17 | F(000) = 1450 |
Mr = 1666.9 | Dx = 5.940 Mg m−3 |
Hexagonal, P63/mmc | Mo Kα radiation, λ = 0.71069 Å |
Hall symbol: -P 6c;-2c | µ = 21.93 mm−1 |
a = 5.6611 (1) Å | T = 293 K |
c = 33.5672 (8) Å | Hexagonal platelets, black |
V = 931.64 (3) Å3 | 0.12 × 0.09 × 0.06 mm |
Z = 2 |
Data collection top
Bruker APEX 11, CCD 4K diffractometer | 1045 reflections with I > 3σ(I) |
φ and ω scans | Rint = 0.045 |
Absorption correction: multi-scan | θmax = 39.9°, θmin = 1.2° |
Tmin = 0.139, Tmax = 0.518 | h = −10→10 |
11909 measured reflections | k = −5→8 |
1158 independent reflections | l = −60→60 |
Refinement top
Refinement on F | Weighting scheme based on measured s.u.'s w = 1/σ2(F) |
R[F2 > 2σ(F2)] = 0.048 | (Δ/σ)max = 0.001 |
wR(F2) = 0.066 | Δρmax = 7.98 e Å−3 |
S = 4.70 | Δρmin = −5.50 e Å−3 |
1158 reflections | Extinction correction: B-C type 1 Gaussian isotropic (Becker & Coppens, 1974) |
53 parameters | Extinction coefficient: 0.028 (8) |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
x | y | z | Uiso*/Ueq | Occ. (<1) | |
Ba1 | 0 | 0 | 0.12114 (2) | 0.00937 (16) | |
Ba2 | 0.333333 | 0.666667 | 0.186738 (18) | 0.00824 (15) | |
Ba3 | 0 | 0 | 0.25 | 0.0115 (2) | |
Ba4 | 0.30479 (11) | 0.6096 (2) | 0.96009 (3) | 0.0134 (5) | 0.3333 |
Co1 | 0.333333 | 0.666667 | 0.85919 (4) | 0.0063 (3) | |
Co2 | 0.333333 | 0.666667 | 0.78574 (4) | 0.0057 (3) | |
Co3 | 0.333333 | 0.666667 | 0.08606 (5) | 0.0089 (3) | |
Br1 | 0 | 0 | 0.4804 (4) | 0.035 (2) | 0.437 (15) |
Br2 | 0 | 0 | 0.5 | 0.023 (6) | 0.13 (3) |
O1 | 0.4955 (4) | 0.9911 (9) | 0.89323 (17) | 0.0139 (13) | |
O2 | 0.1872 (4) | 0.3744 (8) | 0.82175 (13) | 0.0080 (11) | |
O3 | 0.5170 (6) | 0.0339 (12) | 0.25 | 0.0092 (17) | |
O4 | 0.2798 (17) | 0.560 (3) | 0.0343 (5) | 0.036 (7) | 0.3333 |
Atomic displacement parameters (Å2) top
U11 | U22 | U33 | U12 | U13 | U23 | |
Ba1 | 0.00775 (19) | 0.00775 (19) | 0.0126 (3) | 0.00387 (10) | 0 | 0 |
Ba2 | 0.00653 (19) | 0.00653 (19) | 0.0117 (3) | 0.00326 (10) | 0 | 0 |
Ba3 | 0.0070 (2) | 0.0070 (2) | 0.0205 (4) | 0.00348 (12) | 0 | 0 |
Ba4 | 0.0134 (4) | 0.0184 (8) | 0.0100 (3) | 0.0092 (4) | −0.00033 (16) | −0.0007 (3) |
Co1 | 0.0058 (3) | 0.0058 (3) | 0.0072 (5) | 0.00292 (17) | 0 | 0 |
Co2 | 0.0046 (3) | 0.0046 (3) | 0.0078 (5) | 0.00231 (17) | 0 | 0 |
Co3 | 0.0086 (4) | 0.0086 (4) | 0.0096 (6) | 0.0043 (2) | 0 | 0 |
Br1 | 0.0261 (12) | 0.0261 (12) | 0.053 (7) | 0.0130 (6) | 0 | 0 |
Br2 | 0.033 (7) | 0.033 (7) | 0.003 (13) | 0.017 (3) | 0 | 0 |
O1 | 0.0129 (14) | 0.0121 (19) | 0.016 (2) | 0.0061 (10) | −0.0021 (9) | −0.0043 (17) |
O2 | 0.0096 (14) | 0.0042 (16) | 0.0083 (15) | 0.0021 (8) | 0.0004 (7) | 0.0009 (13) |
O3 | 0.0105 (19) | 0.010 (3) | 0.007 (2) | 0.0049 (13) | 0 | 0 |
O4 | 0.053 (9) | 0.033 (10) | 0.015 (7) | 0.017 (5) | 0.000 (3) | 0.001 (7) |
(II) top
Crystal data top
Ba6BrCo5O14 | F(000) = 1854 |
Mr = 1422.6 | Dx = 5.920 Mg m−3 |
Trigonal, R3m | Mo Kα radiation, λ = 0.71069 Å |
Hall symbol: -R 3;-2" | µ = 22.16 mm−1 |
a = 5.6578 (3) Å | T = 293 K |
c = 43.166 (4) Å | Hexagonal platelets, black |
V = 1196.65 (14) Å3 | 0.13 × 0.10 × 0.06 mm |
Z = 3 |
Data collection top
Bruker APEX 11, CCD 4K diffractometer | 1117 reflections with I > 3σ(I) |
φ and ω scans | Rint = 0.045 |
Absorption correction: multi-scan | θmax = 43.8°, θmin = 1.4° |
Tmin = 0.128, Tmax = 0.265 | h = −5→10 |
13868 measured reflections | k = −10→10 |
1232 independent reflections | l = −80→84 |
Refinement top
Refinement on F | Weighting scheme based on measured s.u.'s w = 1/σ2(F) |
R[F2 > 2σ(F2)] = 0.032 | (Δ/σ)max = 0.0004 |
wR(F2) = 0.047 | Δρmax = 4.36 e Å−3 |
S = 3.86 | Δρmin = −4.12 e Å−3 |
1232 reflections | Extinction correction: B-C type 1 Lorentzian isotropic (Becker & Coppens, 1974) |
46 parameters | Extinction coefficient: 0.023 (5) |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
x | y | z | Uiso*/Ueq | Occ. (<1) | |
Ba1 | 0 | 0 | 0.093083 (9) | 0.00958 (9) | |
Ba2 | 0 | 0 | 0.810512 (9) | 0.00961 (9) | |
Ba3 | 0.30796 (8) | −0.30796 (8) | 0.031094 (14) | 0.0153 (2) | 0.3333 |
Co1 | 0 | 0 | 0.44255 (2) | 0.00649 (16) | |
Co2 | 0 | 0 | 0.5 | 0.0061 (2) | |
Co3 | 0 | 0 | 0.73297 (2) | 0.00947 (18) | |
Br1 | 0 | 0 | 0.98409 (11) | 0.0225 (19) | 0.23 (3) |
Br2 | 0 | 0 | 0 | 0.097 (14) | 0.55 (5) |
O1 | 0.4941 (2) | −0.4941 (2) | 0.08305 (7) | 0.0152 (8) | |
O2 | 0.4809 (2) | −0.4809 (2) | 0.19494 (6) | 0.0091 (6) | |
O3 | 0.2800 (10) | −0.2800 (10) | 0.9726 (2) | 0.031 (3) | 0.3333 |
Atomic displacement parameters (Å2) top
U11 | U22 | U33 | U12 | U13 | U23 | |
Ba1 | 0.00808 (11) | 0.00808 (11) | 0.01257 (15) | 0.00404 (6) | 0 | 0 |
Ba2 | 0.00743 (11) | 0.00743 (11) | 0.01396 (16) | 0.00372 (6) | 0 | 0 |
Ba3 | 0.0154 (3) | 0.0154 (3) | 0.0119 (2) | 0.00541 (19) | 0.00141 (10) | −0.00141 (10) |
Co1 | 0.00549 (19) | 0.00549 (19) | 0.0085 (3) | 0.00274 (9) | 0 | 0 |
Co2 | 0.0053 (2) | 0.0053 (2) | 0.0077 (4) | 0.00266 (12) | 0 | 0 |
Co3 | 0.0088 (2) | 0.0088 (2) | 0.0108 (3) | 0.00440 (11) | 0 | 0 |
Br1 | 0.022 (2) | 0.022 (2) | 0.023 (4) | 0.0112 (10) | 0 | 0 |
Br2 | 0.0425 (19) | 0.0425 (19) | 0.21 (4) | 0.0212 (9) | 0 | 0 |
O1 | 0.0137 (9) | 0.0137 (9) | 0.0217 (12) | 0.0096 (9) | 0.0014 (5) | −0.0014 (5) |
O2 | 0.0093 (7) | 0.0093 (7) | 0.0102 (8) | 0.0059 (8) | −0.0006 (4) | 0.0006 (4) |
O3 | 0.036 (4) | 0.036 (4) | 0.010 (3) | 0.009 (4) | 0.0028 (17) | −0.0028 (17) |