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The crystal structure of Rb
CoBr
at 295 and 200 K has been determined. At these temperatures Rb
CoBr
exhibits an incommensurately modulated structure with wavevector
. At room temperature only the average structure was refined. Lattice parameters are
a = 9.732 (3),
b = 13.328 (4),
c = 7.654 (3) Å, space group
Pnam. The
R(
F) value was 0.0414 for 286 observed reflections (0.0778 for all 477 reflections). At 200 K the lattice parameters are
a = 9.691 (4),
b = 13.278 (5),
c = 7.630 (6) Å, superspace group
P:
Pnam:
ss. Main reflections and satellite reflections of first order were measured. The refinement converged at
R(
F) = 0.052 for 309 observed reflections (255 main reflections and 54 satellites) and 0.2971 for all reflections (1849; 695 main reflections and 1154 satellites). Amplitudes and phases of the modulation function as well as bond distances show close relationships to those observed in the incommensurately modulated phase of Rb
ZnBr
.
Supporting information
For both compounds, data collection: STOE IPDS; cell refinement: STOE IPDS. Data reduction: X-RED (STOE & CIE, GmbH 1998) for rcb110. Program(s) used to solve structure: SHELXS97 (Sheldrick, 1990) for rcb110. Program(s) used to refine structure: JANA98 (Petricek & Dusek,1998) for rbcobr; SHELXL97 (Sheldrick, 1997) for rcb110.
Crystal data top
Rb2CoBr4 | F(000) = 964 |
Mr = 549.5 | Dx = 3.717 Mg m−3 |
Orthorhombic, Pnam | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2c -2n | Cell parameters from 707 reflections |
a = 9.691 (4) Å | θ = 2.5–45° |
b = 13.278 (5) Å | µ = 27.79 mm−1 |
c = 7.630 (6) Å | T = 200 K |
V = 981.8 (16) Å3 | Irregular, blue-green |
Z = 4 | 0.12 × 0.08 × 0.02 mm |
Data collection top
IPDS Stoe diffractometer | 309 reflections with I > 2σ(I) |
θ–dependant scans | Rint = 0.485 |
Absorption correction: gaussian XRED (STOE & CIE GmbH, 1998) | θmax = 23.8°, θmin = 2.6° |
Tmin = 0.024, Tmax = 0.069 | h = −10→10 |
15154 measured reflections | k = −14→13 |
1849 independent reflections | l = −8→8 |
Refinement top
Refinement on F | 56 parameters |
R[F > 3σ(F)] = 0.297 | Weighting scheme based on measured s.u.'s w = 1/σ2(F) |
wR(F) = 0.038 | (Δ/σ)max = 0.0001 |
S = 1.77 | Δρmax = 5.43 e Å−3 |
1849 reflections | Δρmin = −6.05 e Å−3 |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Uiso*/Ueq | |
Rb | 0.0132 (4) | 0.6755 (3) | 0.25 | 0.038 (2) | |
Rb2 | 0.3736 (5) | 0.4025 (4) | 0.25 | 0.063 (2) | |
Co | 0.7760 (4) | 0.4232 (4) | 0.25 | 0.035 (2) | |
Br1 | 1.0196 (4) | 0.4160 (4) | 0.25 | 0.056 (3) | |
Br2 | 0.6771 (4) | 0.5864 (4) | 0.25 | 0.050 (3) | |
Br3 | 0.6870 (4) | 0.3395 (3) | 0.5003 (6) | 0.062 (2) | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
Rb | 0.033 (2) | 0.036 (2) | 0.043 (3) | −0.002 (2) | 0 | 0 |
Rb2 | 0.045 (3) | 0.098 (5) | 0.044 (4) | 0.007 (3) | 0 | 0 |
Co | 0.037 (3) | 0.046 (4) | 0.020 (3) | 0.003 (3) | 0 | 0 |
Br1 | 0.035 (3) | 0.066 (4) | 0.068 (6) | 0.003 (3) | 0 | 0 |
Br2 | 0.033 (3) | 0.045 (3) | 0.071 (8) | 0.005 (3) | 0 | 0 |
Br3 | 0.063 (3) | 0.090 (5) | 0.033 (2) | −0.030 (4) | −0.005 (3) | 0.028 (3) |
(rcb110) Rubidium Tetra Bromo Cobaltate
top
Crystal data top
Rb2CoBr4 | Dx = 3.676 Mg m−3 |
Mr = 274.76 | Mo Kα radiation, λ = 0.71073 Å |
Orthorhombic, Pnam | Cell parameters from 1204 reflections |
Hall symbol: -P 2c -2n | θ = 2–40° |
a = 9.732 (3) Å | µ = 27.48 mm−1 |
b = 13.328 (4) Å | T = 293 K |
c = 7.654 (3) Å | Irregular, blue-green |
V = 992.8 (6) Å3 | 0.12 × 0.08 × 0.02 mm |
F(000) = 964 | |
Data collection top
STOE IPDS diffractometer | 477 independent reflections |
Radiation source: fine-focus sealed tube | 286 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.124 |
Imaging plate scans | θmax = 19.5°, θmin = 2.6° |
Absorption correction: gaussian XRED (STOE & CIE GmbH, 1998) | h = −9→9 |
Tmin = 0.024, Tmax = 0.069 | k = −12→11 |
2800 measured reflections | l = −7→7 |
Refinement top
Refinement on F2 | 0 restraints |
Least-squares matrix: full | Primary atom site location: model |
R[F2 > 2σ(F2)] = 0.041 | Secondary atom site location: difference Fourier map |
wR(F2) = 0.100 | Calculated w = 1/[σ2(Fo2) + (0.0518P)2] where P = (Fo2 + 2Fc2)/3 |
S = 0.81 | (Δ/σ)max < 0.001 |
477 reflections | Δρmax = 0.66 e Å−3 |
40 parameters | Δρmin = −0.83 e Å−3 |
Special details top
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) top | x | y | z | Uiso*/Ueq | |
Rb | 0.0149 (3) | 0.6764 (3) | 0.25 | 0.0570 (9) | |
Rb2 | 0.3712 (3) | 0.4028 (3) | 0.25 | 0.081 (1) | |
Co | 0.7742 (4) | 0.4231 (3) | 0.25 | 0.039 (1) | |
Br1 | 0.0183 (3) | 0.4149 (3) | 0.25 | 0.087 (1) | |
Br2 | 0.6802 (4) | 0.5881 (3) | 0.25 | 0.101 (2) | |
Br3 | 0.6840 (3) | 0.3414 (2) | 0.5013 (3) | 0.102 (1) | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
Rb1 | 0.043 (2) | 0.052 (2) | 0.076 (2) | −0.0016 (18) | 0.000 | 0.000 |
Rb2 | 0.046 (2) | 0.127 (3) | 0.087 (2) | −0.001 (3) | 0.000 | 0.000 |
Co1 | 0.034 (2) | 0.041 (3) | 0.0400 (19) | −0.002 (2) | 0.000 | 0.000 |
Br1 | 0.036 (2) | 0.074 (3) | 0.151 (3) | 0.011 (2) | 0.000 | 0.000 |
Br2 | 0.052 (2) | 0.048 (2) | 0.202 (4) | 0.011 (2) | 0.000 | 0.000 |
Br3 | 0.0781 (18) | 0.165 (3) | 0.0627 (14) | −0.042 (2) | −0.0134 (13) | 0.0546 (17) |
Geometric parameters (Å, º) top
Rb1—Br2i | 3.464 (5) | Rb2—Br3iv | 3.941 (5) |
Rb1—Br1 | 3.486 (5) | Rb2—Br3v | 3.941 (5) |
Rb1—Br3ii | 3.494 (4) | Rb2—Rb1xii | 4.998 (4) |
Rb1—Br3iii | 3.494 (4) | Rb2—Rb1xiii | 4.998 (4) |
Rb1—Br3iv | 3.502 (4) | Co1—Br2 | 2.381 (5) |
Rb1—Br3v | 3.502 (4) | Co1—Br3x | 2.378 (3) |
Rb1—Br2vi | 3.527 (5) | Co1—Br3 | 2.378 (3) |
Rb1—Br1vii | 4.029 (2) | Co1—Br1xiv | 2.378 (5) |
Rb1—Br1viii | 4.029 (2) | Co1—Rb1xiv | 4.109 (5) |
Rb1—Co1i | 4.109 (5) | Br1—Co1i | 2.378 (5) |
Rb1—Rb2ix | 4.998 (4) | Br1—Rb1vii | 4.029 (2) |
Rb1—Rb2iii | 4.998 (4) | Br1—Rb1viii | 4.029 (2) |
Rb2—Br1 | 3.439 (5) | Br2—Rb1xiv | 3.464 (5) |
Rb2—Br3 | 3.693 (4) | Br2—Rb1xv | 3.527 (5) |
Rb2—Br3x | 3.693 (4) | Br2—Rb2xi | 3.8615 (16) |
Rb2—Br2xi | 3.8615 (16) | Br2—Rb2iv | 3.8615 (16) |
Rb2—Br2iv | 3.8615 (16) | Br3—Rb1xiii | 3.494 (4) |
Rb2—Br2 | 3.891 (5) | Br3—Rb1iv | 3.502 (4) |
Rb2—Co1 | 3.931 (5) | Br3—Rb2iv | 3.941 (5) |
| | | |
Br2i—Rb1—Br1 | 70.66 (10) | Br2iv—Rb2—Br3iv | 58.43 (7) |
Br2i—Rb1—Br3ii | 72.11 (9) | Br2—Rb2—Br3iv | 63.68 (8) |
Br1—Rb1—Br3ii | 129.39 (10) | Co1—Rb2—Br3iv | 94.39 (10) |
Br2i—Rb1—Br3iii | 72.11 (9) | Br1—Rb2—Br3v | 79.82 (10) |
Br1—Rb1—Br3iii | 129.39 (10) | Br3—Rb2—Br3v | 123.77 (11) |
Br3ii—Rb1—Br3iii | 66.03 (11) | Br3x—Rb2—Br3v | 93.02 (9) |
Br2i—Rb1—Br3iv | 139.79 (7) | Br2xi—Rb2—Br3v | 58.43 (7) |
Br1—Rb1—Br3iv | 85.65 (9) | Br2iv—Rb2—Br3v | 115.72 (12) |
Br3ii—Rb1—Br3iv | 102.13 (8) | Br2—Rb2—Br3v | 63.68 (8) |
Br3iii—Rb1—Br3iv | 143.37 (10) | Co1—Rb2—Br3v | 94.39 (10) |
Br2i—Rb1—Br3v | 139.79 (7) | Br3iv—Rb2—Br3v | 57.77 (9) |
Br1—Rb1—Br3v | 85.65 (9) | Br1—Rb2—Rb1xii | 104.46 (8) |
Br3ii—Rb1—Br3v | 143.37 (10) | Br3—Rb2—Rb1xii | 94.71 (9) |
Br3iii—Rb1—Br3v | 102.13 (8) | Br3x—Rb2—Rb1xii | 44.33 (6) |
Br3iv—Rb1—Br3v | 65.86 (10) | Br2xi—Rb2—Rb1xii | 44.67 (7) |
Br2i—Rb1—Br2vi | 137.01 (12) | Br2iv—Rb2—Rb1xii | 143.76 (12) |
Br1—Rb1—Br2vi | 152.33 (13) | Br2—Rb2—Rb1xii | 102.23 (7) |
Br3ii—Rb1—Br2vi | 72.10 (9) | Co1—Rb2—Rb1xii | 79.65 (7) |
Br3iii—Rb1—Br2vi | 72.10 (9) | Br3iv—Rb2—Rb1xii | 157.27 (9) |
Br3iv—Rb1—Br2vi | 71.27 (9) | Br3v—Rb2—Rb1xii | 100.52 (5) |
Br3v—Rb1—Br2vi | 71.27 (9) | Br1—Rb2—Rb1xiii | 104.46 (8) |
Br2i—Rb1—Br1vii | 79.74 (6) | Br3—Rb2—Rb1xiii | 44.33 (6) |
Br1—Rb1—Br1vii | 72.47 (7) | Br3x—Rb2—Rb1xiii | 94.71 (9) |
Br3ii—Rb1—Br1vii | 131.55 (9) | Br2xi—Rb2—Rb1xiii | 143.76 (12) |
Br3iii—Rb1—Br1vii | 68.17 (7) | Br2iv—Rb2—Rb1xiii | 44.67 (7) |
Br3iv—Rb1—Br1vii | 124.26 (10) | Br2—Rb2—Rb1xiii | 102.23 (7) |
Br3v—Rb1—Br1vii | 61.97 (6) | Co1—Rb2—Rb1xiii | 79.65 (7) |
Br2vi—Rb1—Br1vii | 107.78 (6) | Br3iv—Rb2—Rb1xiii | 100.52 (5) |
Br2i—Rb1—Br1viii | 79.74 (6) | Br3v—Rb2—Rb1xiii | 157.27 (9) |
Br1—Rb1—Br1viii | 72.47 (7) | Rb1xii—Rb2—Rb1xiii | 99.94 (10) |
Br3ii—Rb1—Br1viii | 68.17 (7) | Br1—Rb2—Rb1 | 43.76 (9) |
Br3iii—Rb1—Br1viii | 131.55 (9) | Br3—Rb2—Rb1 | 136.78 (10) |
Br3iv—Rb1—Br1viii | 61.97 (6) | Br3x—Rb2—Rb1 | 136.78 (10) |
Br3v—Rb1—Br1viii | 124.26 (10) | Br2xi—Rb2—Rb1 | 83.57 (8) |
Br2vi—Rb1—Br1viii | 107.78 (6) | Br2iv—Rb2—Rb1 | 83.57 (8) |
Br1vii—Rb1—Br1viii | 143.58 (13) | Br2—Rb2—Rb1 | 94.17 (11) |
Br2i—Rb1—Co1i | 35.36 (8) | Co1—Rb2—Rb1 | 129.61 (12) |
Br1—Rb1—Co1i | 35.30 (8) | Br3iv—Rb2—Rb1 | 43.88 (6) |
Br3ii—Rb1—Co1i | 101.60 (9) | Br3v—Rb2—Rb1 | 43.88 (6) |
Br3iii—Rb1—Co1i | 101.60 (9) | Rb1xii—Rb2—Rb1 | 126.18 (4) |
Br3iv—Rb1—Co1i | 114.91 (9) | Rb1xiii—Rb2—Rb1 | 126.18 (4) |
Br3v—Rb1—Co1i | 114.91 (9) | Br2—Co1—Br3x | 106.33 (14) |
Br2vi—Rb1—Co1i | 172.37 (12) | bR2—Co1—Br3 | 106.33 (14) |
Br1vii—Rb1—Co1i | 72.91 (6) | Br3x—Co1—Br3 | 108.0 (2) |
Br1viii—Rb1—Co1i | 72.91 (6) | Br2—Co1—Br1xiv | 115.25 (19) |
Br2i—Rb1—Rb2ix | 114.44 (6) | Br3x—Co1—Br1xiv | 110.32 (13) |
Br1—Rb1—Rb2ix | 126.99 (6) | Br3—Co1—Br1xiv | 110.32 (13) |
Br3ii—Rb1—Rb2ix | 47.60 (6) | Br2—Co1—Rb2 | 71.36 (13) |
Br3iii—Rb1—Rb2ix | 99.21 (10) | Br3x—Co1—Rb2 | 66.45 (10) |
Br3iv—Rb1—Rb2ix | 55.89 (7) | Br3—Co1—Rb2 | 66.45 (10) |
Br3v—Rb1—Rb2ix | 105.77 (8) | Br1xiv—Co1—Rb2 | 173.40 (17) |
Br2vi—Rb1—Rb2ix | 50.32 (5) | Br2—Co1—Rb1xiv | 57.35 (12) |
Br1vii—Rb1—Rb2ix | 158.05 (9) | Br3x—Co1—Rb1xiv | 125.91 (10) |
Br1viii—Rb1—Rb2ix | 58.18 (6) | Br3—Co1—Rb1xiv | 125.92 (10) |
Co1i—Rb1—Rb2ix | 128.49 (5) | Br1xiv—Co1—Rb1xiv | 57.89 (12) |
Br2i—Rb1—Rb2iii | 114.44 (6) | Rb2—Co1—Rb1xiv | 128.71 (12) |
Br1—Rb1—Rb2iii | 126.99 (6) | Co1i—Br1—Rb2 | 179.98 (15) |
Br3ii—Rb1—Rb2iii | 99.21 (10) | Co1i—Br1—Rb1 | 86.81 (14) |
Br3iii—Rb1—Rb2iii | 47.60 (6) | Rb2—Br1—Rb1 | 93.22 (13) |
Br3iv—Rb1—Rb2iii | 105.77 (8) | Co1i—Br1—Rb1vii | 86.21 (7) |
Br3v—Rb1—Rb2iii | 55.89 (7) | Rb2—Br1—Rb1vii | 93.78 (7) |
Br2vi—Rb1—Rb2iii | 50.32 (5) | Rb1—Br1—Rb1vii | 107.54 (7) |
Br1vii—Rb1—Rb2iii | 58.18 (6) | Co1i—Br1—Rb1viii | 86.21 (7) |
Br1viii—Rb1—Rb2iii | 158.05 (9) | Rb2—Br1—Rb1viii | 93.78 (7) |
Co1i—Rb1—Rb2iii | 128.49 (5) | Rb1—Br1—Rb1viii | 107.54 (7) |
Rb2ix—Rb1—Rb2iii | 99.94 (10) | Rb1vii—Br1—Rb1viii | 143.58 (13) |
Br1—Rb2—Br3 | 146.50 (7) | Co1—Br2—Rb1xiv | 87.28 (14) |
Br1—Rb2—Br3x | 146.50 (7) | Co1—Br2—Rb1xv | 175.46 (17) |
Br3—Rb2—Br3x | 62.77 (10) | Rb1xiv—Br2—Rb1xv | 97.26 (10) |
Br1—Rb2—Br2xi | 82.48 (7) | Co1—Br2—Rb2xi | 94.52 (9) |
Br3—Rb2—Br2xi | 129.04 (10) | Rb1xiv—Br2—Rb2xi | 96.38 (7) |
Br3x—Rb2—Br2xi | 66.28 (7) | Rb1xv—Br2—Rb2xi | 85.01 (8) |
Br1—Rb2—Br2iv | 82.48 (7) | Co1—Br2—Rb2iv | 94.52 (9) |
Br3—Rb2—Br2iv | 66.27 (7) | Rb1xiv—Br2—Rb2iv | 96.38 (7) |
Br3x—Rb2—Br2iv | 129.04 (10) | Rb1xv—Br2—Rb2iv | 85.01 (8) |
Br2xi—Rb2—Br2iv | 164.68 (14) | Rb2xi—Br2—Rb2iv | 164.67 (14) |
Br1—Rb2—Br2 | 137.93 (16) | Co1—Br2—Rb2 | 73.20 (13) |
Br3—Rb2—Br2 | 60.23 (8) | Rb1xiv—Br2—Rb2 | 160.49 (13) |
Br3x—Rb2—Br2 | 60.23 (8) | Rb1xv—Br2—Rb2 | 102.25 (11) |
Br2xi—Rb2—Br2 | 94.60 (8) | Rb2xi—Br2—Rb2 | 85.40 (8) |
Br2iv—Rb2—Br2 | 94.60 (8) | Rb2iv—Br2—Rb2 | 85.40 (8) |
Br1—Rb2—Co1 | 173.37 (16) | Co1—Br3—Rb1xiii | 158.96 (14) |
Br3—Rb2—Co1 | 36.18 (5) | Co1—Br3—Rb1iv | 99.34 (11) |
Br3x—Rb2—Co1 | 36.18 (5) | Rb1xiii—Br3—Rb1iv | 97.16 (7) |
Br2xi—Rb2—Co1 | 97.30 (7) | Co1—Br3—Rb2 | 77.37 (11) |
Br2iv—Rb2—Co1 | 97.30 (7) | Rb1xiii—Br3—Rb2 | 88.08 (9) |
Br2—Rb2—Co1 | 35.44 (8) | Rb1iv—Br3—Rb2 | 171.06 (13) |
Br1—Rb2—Br3iv | 79.82 (10) | Co1—Br3—Rb2iv | 92.58 (13) |
Br3—Rb2—Br3iv | 93.02 (9) | Rb1xiii—Br3—Rb2iv | 101.86 (9) |
Br3x—Rb2—Br3iv | 123.76 (11) | Rb1iv—Br3—Rb2iv | 84.86 (9) |
Br2xi—Rb2—Br3iv | 115.72 (12) | Rb2—Br3—Rb2iv | 86.98 (9) |
Symmetry codes: (i) x−1, y, z; (ii) −x+1/2, y+1/2, −z+1; (iii) −x+1/2, y+1/2, z−1/2; (iv) −x+1, −y+1, −z+1; (v) −x+1, −y+1, z−1/2; (vi) x−1/2, −y+3/2, −z+1/2; (vii) −x, −y+1, −z; (viii) −x, −y+1, −z+1; (ix) −x+1/2, y+1/2, z+1/2; (x) x, y, −z+1/2; (xi) −x+1, −y+1, −z; (xii) −x+1/2, y−1/2, z−1/2; (xiii) −x+1/2, y−1/2, z+1/2; (xiv) x+1, y, z; (xv) x+1/2, −y+3/2, −z+1/2. |
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