Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270109036865/bd3006sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270109036865/bd3006Isup2.hkl |
Single crystals of a new monoclinic polymorph of Cu3B2O6 were obtained by melting a mixture of LiBO2 and CuO at 1273 K in air and then cooling it slowly to room temperature. All attempts to obtain the monoclinic form by quenching of a stoichiometric mixture of CuO and B2O3 from 1273 K in air led to the formation of the triclinic form of Cu3B2O6. High-temperature powder X-ray diffraction data of triclinic Cu3B2O6 from room temperature up to 1073 K yielded no phase transformation.
Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008) and BS (Ozawa & Kang, 2004); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).
Cu9B6O18 | F(000) = 1740 |
Mr = 924.81 | Dx = 4.433 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 2562 reflections |
a = 17.820 (2) Å | θ = 2.7–31.8° |
b = 8.5232 (12) Å | µ = 13.64 mm−1 |
c = 9.1706 (12) Å | T = 296 K |
β = 95.913 (6)° | Prism, green |
V = 1385.4 (3) Å3 | 0.20 × 0.20 × 0.15 mm |
Z = 4 |
Bruker Kappa APEXII CCD area-detector diffractometer | 3410 independent reflections |
Radiation source: fine-focus sealed tube | 2542 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.036 |
Detector resolution: 25 pixels mm-1 | θmax = 28.3°, θmin = 1.2° |
ϕ scans | h = −14→23 |
Absorption correction: multi-scan (SADABS; Bruker, 2004) | k = −11→11 |
Tmin = 0.101, Tmax = 0.153 | l = −8→12 |
9748 measured reflections |
Refinement on F2 | 0 restraints |
Least-squares matrix: full | Primary atom site location: structure-invariant direct methods |
R[F2 > 2σ(F2)] = 0.030 | Secondary atom site location: difference Fourier map |
wR(F2) = 0.063 | w = 1/[σ2(Fo2) + (0.0316P)2] where P = (Fo2 + 2Fc2)/3 |
S = 0.96 | (Δ/σ)max = 0.001 |
3410 reflections | Δρmax = 1.11 e Å−3 |
301 parameters | Δρmin = −0.91 e Å−3 |
Cu9B6O18 | V = 1385.4 (3) Å3 |
Mr = 924.81 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 17.820 (2) Å | µ = 13.64 mm−1 |
b = 8.5232 (12) Å | T = 296 K |
c = 9.1706 (12) Å | 0.20 × 0.20 × 0.15 mm |
β = 95.913 (6)° |
Bruker Kappa APEXII CCD area-detector diffractometer | 3410 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2004) | 2542 reflections with I > 2σ(I) |
Tmin = 0.101, Tmax = 0.153 | Rint = 0.036 |
9748 measured reflections |
R[F2 > 2σ(F2)] = 0.030 | 301 parameters |
wR(F2) = 0.063 | 0 restraints |
S = 0.96 | Δρmax = 1.11 e Å−3 |
3410 reflections | Δρmin = −0.91 e Å−3 |
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. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
Cu1 | 0.05596 (3) | 0.32007 (7) | 0.66267 (7) | 0.01518 (15) | |
Cu2 | 0.14770 (3) | 1.08020 (7) | 0.52540 (6) | 0.00941 (13) | |
Cu3 | 0.09805 (4) | 0.70984 (7) | 0.66138 (8) | 0.01764 (15) | |
Cu4 | 0.26208 (3) | 0.25771 (7) | 0.28273 (6) | 0.00880 (13) | |
Cu5 | 0.25274 (3) | 0.59337 (7) | 0.25439 (6) | 0.00897 (13) | |
Cu6 | 0.26838 (3) | 0.92391 (7) | 0.27160 (6) | 0.00941 (13) | |
Cu7 | 0.36673 (3) | 0.76126 (7) | 0.00016 (6) | 0.00842 (13) | |
Cu8 | 0.43525 (3) | 0.39597 (7) | −0.08558 (6) | 0.00916 (13) | |
Cu9 | 0.43942 (3) | 1.01033 (7) | −0.16993 (7) | 0.01316 (14) | |
B1 | −0.0131 (3) | 0.5000 (7) | 0.7998 (7) | 0.0148 (12) | |
O11A | 0.0572 (3) | 0.5301 (6) | 0.7488 (6) | 0.0200 (13) | 0.80 |
O11B | 0.0329 (13) | 0.537 (3) | 0.690 (3) | 0.0200 (13) | 0.20 |
O12 | −0.05446 (19) | 0.5998 (4) | 0.8738 (4) | 0.0156 (8) | |
O13 | −0.0292 (2) | 0.3457 (4) | 0.7684 (5) | 0.0297 (10) | |
B21 | 0.2070 (3) | 0.7422 (6) | 0.5130 (6) | 0.0088 (11) | |
B22 | 0.1715 (3) | 0.4394 (7) | 0.4847 (6) | 0.0113 (11) | |
O21 | 0.15759 (17) | 0.8592 (4) | 0.5667 (3) | 0.0087 (7) | |
O22 | 0.16421 (18) | 0.5886 (4) | 0.5438 (4) | 0.0107 (7) | |
O23 | 0.21858 (18) | 0.7596 (4) | 0.3627 (3) | 0.0101 (7) | |
O24 | 0.27939 (18) | 0.7356 (4) | 0.6133 (4) | 0.0091 (7) | |
O25 | 0.21256 (19) | 0.4261 (4) | 0.3697 (4) | 0.0133 (7) | |
O26 | 0.13875 (19) | 0.3143 (4) | 0.5437 (4) | 0.0174 (8) | |
B31 | 0.3116 (3) | 0.4163 (6) | 0.0241 (6) | 0.0091 (11) | |
B32 | 0.3488 (3) | 0.1150 (6) | 0.0580 (6) | 0.0094 (11) | |
O31 | 0.35989 (17) | 0.5374 (4) | −0.0307 (3) | 0.0087 (7) | |
O32 | 0.35636 (18) | 0.2651 (4) | −0.0047 (3) | 0.0097 (7) | |
O33 | 0.30315 (18) | 0.4254 (4) | 0.1756 (3) | 0.0099 (7) | |
O34 | 0.23944 (17) | 0.4097 (4) | −0.0764 (4) | 0.0090 (7) | |
O35 | 0.30901 (19) | 0.0989 (4) | 0.1753 (4) | 0.0124 (7) | |
O36 | 0.38450 (18) | −0.0077 (4) | 0.0005 (3) | 0.0101 (7) | |
B4 | 0.4777 (3) | 0.6897 (6) | −0.2246 (6) | 0.0086 (10) | |
O41 | 0.42753 (19) | 0.7857 (4) | −0.1693 (4) | 0.0122 (7) | |
O42 | 0.49875 (18) | 0.5434 (4) | −0.1678 (4) | 0.0117 (7) | |
O43 | 0.51419 (19) | 0.7201 (4) | −0.3474 (4) | 0.0150 (8) |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cu1 | 0.0176 (3) | 0.0049 (3) | 0.0260 (4) | −0.0004 (2) | 0.0165 (3) | −0.0009 (3) |
Cu2 | 0.0104 (3) | 0.0045 (3) | 0.0146 (3) | 0.0006 (2) | 0.0072 (2) | 0.0006 (2) |
Cu3 | 0.0187 (3) | 0.0046 (3) | 0.0333 (4) | −0.0010 (2) | 0.0204 (3) | −0.0005 (3) |
Cu4 | 0.0138 (3) | 0.0042 (3) | 0.0094 (3) | 0.0011 (2) | 0.0065 (2) | 0.0008 (2) |
Cu5 | 0.0147 (3) | 0.0040 (3) | 0.0092 (3) | 0.0009 (2) | 0.0062 (2) | −0.0003 (2) |
Cu6 | 0.0160 (3) | 0.0041 (3) | 0.0091 (3) | −0.0022 (2) | 0.0060 (2) | −0.0003 (2) |
Cu7 | 0.0115 (3) | 0.0037 (3) | 0.0111 (3) | −0.0005 (2) | 0.0066 (2) | −0.0001 (2) |
Cu8 | 0.0107 (3) | 0.0044 (3) | 0.0137 (3) | 0.0005 (2) | 0.0075 (2) | 0.0003 (2) |
Cu9 | 0.0194 (3) | 0.0044 (3) | 0.0182 (3) | −0.0011 (2) | 0.0144 (3) | −0.0008 (2) |
B1 | 0.013 (3) | 0.007 (3) | 0.027 (3) | 0.000 (2) | 0.010 (2) | 0.002 (2) |
O11A | 0.018 (3) | 0.007 (2) | 0.039 (4) | −0.006 (2) | 0.019 (2) | −0.009 (3) |
O11B | 0.018 (3) | 0.007 (2) | 0.039 (4) | −0.006 (2) | 0.019 (2) | −0.009 (3) |
O12 | 0.0165 (18) | 0.0064 (18) | 0.027 (2) | −0.0011 (14) | 0.0164 (15) | 0.0015 (15) |
O13 | 0.033 (2) | 0.0079 (19) | 0.054 (3) | −0.0040 (17) | 0.034 (2) | −0.0088 (19) |
B21 | 0.011 (2) | 0.004 (2) | 0.013 (3) | 0.000 (2) | 0.007 (2) | 0.000 (2) |
B22 | 0.015 (3) | 0.009 (3) | 0.011 (3) | 0.000 (2) | 0.008 (2) | 0.001 (2) |
O21 | 0.0104 (16) | 0.0038 (16) | 0.0130 (17) | 0.0001 (13) | 0.0061 (13) | −0.0006 (13) |
O22 | 0.0160 (17) | 0.0043 (16) | 0.0136 (18) | −0.0009 (13) | 0.0097 (14) | −0.0015 (13) |
O23 | 0.0173 (17) | 0.0068 (16) | 0.0069 (17) | 0.0009 (14) | 0.0057 (13) | 0.0017 (13) |
O24 | 0.0114 (16) | 0.0071 (17) | 0.0092 (16) | −0.0014 (13) | 0.0039 (13) | 0.0037 (13) |
O25 | 0.0209 (18) | 0.0026 (16) | 0.0185 (19) | 0.0017 (14) | 0.0120 (14) | 0.0021 (14) |
O26 | 0.0218 (19) | 0.0042 (17) | 0.029 (2) | −0.0002 (15) | 0.0180 (16) | −0.0022 (16) |
B31 | 0.015 (3) | 0.004 (2) | 0.009 (3) | 0.003 (2) | 0.006 (2) | 0.000 (2) |
B32 | 0.009 (2) | 0.006 (3) | 0.013 (3) | −0.001 (2) | 0.004 (2) | 0.000 (2) |
O31 | 0.0112 (16) | 0.0048 (16) | 0.0111 (18) | −0.0008 (13) | 0.0063 (13) | −0.0014 (13) |
O32 | 0.0128 (16) | 0.0081 (17) | 0.0096 (17) | 0.0016 (14) | 0.0071 (13) | 0.0001 (13) |
O33 | 0.0158 (17) | 0.0046 (16) | 0.0107 (17) | 0.0016 (13) | 0.0075 (13) | −0.0001 (13) |
O34 | 0.0102 (16) | 0.0066 (17) | 0.0113 (17) | −0.0009 (13) | 0.0063 (13) | −0.0013 (13) |
O35 | 0.0200 (18) | 0.0055 (17) | 0.0134 (18) | 0.0017 (14) | 0.0093 (14) | 0.0017 (14) |
O36 | 0.0170 (17) | 0.0033 (16) | 0.0122 (17) | 0.0007 (14) | 0.0111 (14) | 0.0020 (13) |
B4 | 0.007 (2) | 0.007 (3) | 0.013 (3) | −0.002 (2) | 0.006 (2) | 0.003 (2) |
O41 | 0.0179 (18) | 0.0047 (17) | 0.0161 (19) | −0.0006 (14) | 0.0122 (14) | 0.0024 (14) |
O42 | 0.0111 (16) | 0.0114 (18) | 0.0141 (18) | 0.0014 (14) | 0.0090 (14) | 0.0032 (14) |
O43 | 0.0222 (19) | 0.0048 (17) | 0.021 (2) | 0.0008 (14) | 0.0141 (15) | −0.0011 (14) |
Cu1—O11A | 1.956 (5) | Cu6—Cu4iii | 2.8494 (9) |
Cu1—O11B | 1.92 (2) | Cu6—Cu7iv | 3.0329 (8) |
Cu1—O12i | 1.906 (3) | Cu7—Cu6vi | 3.0329 (8) |
Cu1—O13 | 1.896 (4) | B1—O12 | 1.354 (7) |
Cu1—O26 | 1.924 (4) | B1—O13 | 1.370 (7) |
Cu2—O12ii | 1.990 (3) | B1—O11B | 1.40 (3) |
Cu2—O21 | 1.925 (3) | B1—O11A | 1.405 (8) |
Cu2—O26iii | 2.010 (3) | O12—Cu1ii | 1.906 (3) |
Cu2—O34iv | 1.967 (3) | O12—Cu2i | 1.990 (3) |
Cu3—O11A | 1.908 (5) | O13—Cu3i | 1.850 (4) |
Cu3—O11B | 1.91 (2) | O21—Cu5iv | 2.324 (3) |
Cu3—O13ii | 1.850 (4) | B21—O21 | 1.451 (6) |
Cu3—O21 | 1.921 (3) | B21—O22 | 1.555 (6) |
Cu3—O22 | 1.970 (3) | B21—O23 | 1.422 (6) |
Cu4—O25 | 1.903 (3) | B21—O24 | 1.506 (6) |
Cu4—O33 | 1.921 (3) | B22—O22 | 1.394 (6) |
Cu4—O34v | 1.994 (3) | B22—O25 | 1.348 (7) |
Cu4—O35 | 1.916 (3) | B22—O26 | 1.355 (6) |
Cu5—O21vi | 2.324 (3) | O24—Cu7iv | 1.958 (3) |
Cu5—O23 | 1.868 (3) | O24—Cu6iv | 2.013 (3) |
Cu5—O24vi | 2.037 (3) | O24—Cu5iv | 2.037 (3) |
Cu5—O25 | 1.954 (3) | O26—Cu2ix | 2.010 (3) |
Cu5—O33 | 1.874 (3) | O31—Cu6vi | 2.333 (3) |
Cu6—O23 | 1.897 (3) | B31—O31 | 1.465 (6) |
Cu6—O24vi | 2.013 (3) | B31—O32 | 1.552 (6) |
Cu6—O31iv | 2.333 (3) | B31—O33 | 1.415 (6) |
Cu6—O34iv | 2.090 (3) | B31—O34 | 1.505 (6) |
Cu6—O35iii | 1.913 (3) | B32—O32 | 1.415 (6) |
Cu7—O24vi | 1.958 (3) | B32—O35 | 1.355 (6) |
Cu7—O31 | 1.931 (3) | B32—O36 | 1.359 (6) |
Cu7—O36iii | 1.994 (3) | O34—Cu2vi | 1.967 (3) |
Cu7—O41 | 1.995 (3) | O34—Cu4x | 1.994 (3) |
Cu8—O31 | 1.910 (3) | O34—Cu6vi | 2.090 (3) |
Cu8—O32 | 1.996 (3) | O35—Cu6ix | 1.913 (3) |
Cu8—O42 | 1.898 (3) | O36—Cu9ix | 1.934 (3) |
Cu8—O43vii | 1.885 (3) | O36—Cu7ix | 1.994 (3) |
Cu9—O36iii | 1.934 (3) | B4—O41 | 1.349 (6) |
Cu9—O41 | 1.926 (3) | B4—O42 | 1.389 (6) |
Cu9—O42viii | 1.961 (3) | B4—O43 | 1.381 (6) |
Cu9—O43viii | 1.969 (3) | O42—Cu9vii | 1.961 (3) |
Cu2—Cu1iii | 2.9767 (9) | O43—Cu8viii | 1.885 (3) |
Cu2—Cu5iv | 3.0484 (9) | O43—Cu9vii | 1.969 (3) |
Cu4—Cu6ix | 2.8494 (9) | O11A—O11B | 0.66 (2) |
Cu5—Cu2vi | 3.0484 (9) | B4—Cu9vii | 2.397 (6) |
O13—Cu1—O12i | 101.87 (16) | O43viii—Cu9—B4viii | 35.17 (16) |
O13—Cu1—O11B | 68.2 (8) | B1—O12—Cu1ii | 122.0 (3) |
O12i—Cu1—O11B | 166.8 (7) | B1—O12—Cu2i | 134.8 (3) |
O13—Cu1—O26 | 173.75 (17) | Cu1ii—O12—Cu2i | 99.62 (16) |
O12i—Cu1—O26 | 82.70 (15) | B1—O13—Cu3i | 131.3 (4) |
O11B—Cu1—O26 | 106.6 (8) | B1—O13—Cu1 | 93.2 (3) |
O13—Cu1—O11A | 70.39 (19) | Cu3i—O13—Cu1 | 134.5 (2) |
O12i—Cu1—O11A | 166.3 (2) | B21—O21—Cu3 | 94.6 (3) |
O11B—Cu1—O11A | 19.6 (6) | B21—O21—Cu2 | 130.7 (3) |
O26—Cu1—O11A | 105.97 (19) | Cu3—O21—Cu2 | 133.92 (18) |
O21—Cu2—O34iv | 94.15 (13) | B21—O21—Cu5iv | 87.1 (2) |
O21—Cu2—O12ii | 93.14 (14) | Cu3—O21—Cu5iv | 100.09 (13) |
O34iv—Cu2—O12ii | 172.65 (14) | Cu2—O21—Cu5iv | 91.19 (12) |
O21—Cu2—O26iii | 163.92 (15) | B22—O22—B21 | 129.0 (4) |
O34iv—Cu2—O26iii | 94.21 (14) | B22—O22—Cu3 | 140.9 (3) |
O12ii—Cu2—O26iii | 78.49 (14) | B21—O22—Cu3 | 89.5 (2) |
O21—Cu2—Cu1iii | 129.18 (10) | B21—O23—Cu5 | 121.6 (3) |
O34iv—Cu2—Cu1iii | 133.67 (10) | B21—O23—Cu6 | 128.7 (3) |
O12ii—Cu2—Cu1iii | 39.16 (10) | Cu5—O23—Cu6 | 97.65 (15) |
O26iii—Cu2—Cu1iii | 39.75 (10) | B21—O24—Cu7iv | 110.7 (3) |
O21—Cu2—Cu5iv | 49.65 (9) | B21—O24—Cu6iv | 109.0 (3) |
O34iv—Cu2—Cu5iv | 82.35 (9) | Cu7iv—O24—Cu6iv | 122.24 (16) |
O12ii—Cu2—Cu5iv | 101.76 (10) | B21—O24—Cu5iv | 96.9 (3) |
O26iii—Cu2—Cu5iv | 118.20 (11) | Cu7iv—O24—Cu5iv | 125.21 (16) |
Cu1iii—Cu2—Cu5iv | 111.53 (3) | Cu6iv—O24—Cu5iv | 88.80 (13) |
O13ii—Cu3—O11A | 93.5 (2) | B22—O25—Cu4 | 134.7 (3) |
O13ii—Cu3—O11B | 90.1 (8) | B22—O25—Cu5 | 128.3 (3) |
O11A—Cu3—O11B | 19.9 (7) | Cu4—O25—Cu5 | 96.42 (16) |
O13ii—Cu3—O21 | 99.16 (15) | B22—O26—Cu1 | 126.4 (3) |
O11A—Cu3—O21 | 167.06 (18) | B22—O26—Cu2ix | 135.0 (3) |
O11B—Cu3—O21 | 160.8 (8) | Cu1—O26—Cu2ix | 98.33 (15) |
O13ii—Cu3—O22 | 166.97 (16) | B31—O31—Cu8 | 95.7 (3) |
O11A—Cu3—O22 | 94.87 (19) | B31—O31—Cu7 | 132.5 (3) |
O11B—Cu3—O22 | 94.4 (8) | Cu8—O31—Cu7 | 128.82 (17) |
O21—Cu3—O22 | 73.19 (13) | B31—O31—Cu6vi | 88.8 (2) |
O25—Cu4—O35 | 173.84 (14) | Cu8—O31—Cu6vi | 109.78 (14) |
O25—Cu4—O33 | 82.57 (14) | Cu7—O31—Cu6vi | 90.17 (12) |
O35—Cu4—O33 | 93.05 (14) | B32—O32—B31 | 127.6 (4) |
O25—Cu4—O34v | 97.75 (14) | B32—O32—Cu8 | 139.1 (3) |
O35—Cu4—O34v | 87.46 (14) | B31—O32—Cu8 | 89.6 (3) |
O33—Cu4—O34v | 167.64 (13) | B31—O33—Cu5 | 121.6 (3) |
O25—Cu4—Cu6ix | 142.18 (11) | B31—O33—Cu4 | 123.1 (3) |
O35—Cu4—Cu6ix | 41.88 (10) | Cu5—O33—Cu4 | 98.53 (15) |
O33—Cu4—Cu6ix | 134.91 (10) | B31—O34—Cu2vi | 114.0 (3) |
O34v—Cu4—Cu6ix | 47.15 (9) | B31—O34—Cu4x | 101.9 (3) |
O23—Cu5—O33 | 168.47 (14) | Cu2vi—O34—Cu4x | 124.93 (16) |
O23—Cu5—O25 | 96.20 (14) | B31—O34—Cu6vi | 97.4 (3) |
O33—Cu5—O25 | 82.42 (14) | Cu2vi—O34—Cu6vi | 124.16 (16) |
O23—Cu5—O24vi | 84.53 (14) | Cu4x—O34—Cu6vi | 88.48 (13) |
O33—Cu5—O24vi | 98.62 (14) | B32—O35—Cu6ix | 134.4 (3) |
O25—Cu5—O24vi | 171.08 (14) | B32—O35—Cu4 | 128.9 (3) |
O23—Cu5—O21vi | 90.52 (13) | Cu6ix—O35—Cu4 | 96.16 (15) |
O33—Cu5—O21vi | 100.93 (13) | B32—O36—Cu9ix | 123.3 (3) |
O25—Cu5—O21vi | 104.33 (13) | B32—O36—Cu7ix | 132.9 (3) |
O24vi—Cu5—O21vi | 66.76 (12) | Cu9ix—O36—Cu7ix | 99.84 (14) |
O23—Cu5—Cu2vi | 121.59 (10) | B4—O41—Cu9 | 121.6 (3) |
O33—Cu5—Cu2vi | 69.42 (10) | B4—O41—Cu7 | 131.6 (3) |
O25—Cu5—Cu2vi | 77.62 (10) | Cu9—O41—Cu7 | 100.08 (15) |
O24vi—Cu5—Cu2vi | 94.40 (9) | B4—O42—Cu8 | 126.5 (3) |
O21vi—Cu5—Cu2vi | 39.16 (8) | B4—O42—Cu9vii | 89.7 (3) |
O23—Cu6—O35iii | 174.33 (14) | Cu8—O42—Cu9vii | 127.65 (18) |
O23—Cu6—O24vi | 84.48 (14) | B4—O43—Cu8viii | 134.1 (3) |
O35iii—Cu6—O24vi | 97.12 (14) | B4—O43—Cu9vii | 89.6 (3) |
O23—Cu6—O34iv | 92.78 (14) | Cu8viii—O43—Cu9vii | 122.53 (18) |
O35iii—Cu6—O34iv | 84.83 (13) | O12—B1—O13 | 126.6 (5) |
O24vi—Cu6—O34iv | 171.19 (13) | O12—B1—O11B | 127.5 (11) |
O23—Cu6—O31iv | 94.78 (12) | O13—B1—O11B | 101.0 (11) |
O35iii—Cu6—O31iv | 88.92 (13) | O12—B1—O11A | 127.0 (5) |
O24vi—Cu6—O31iv | 122.91 (12) | O13—B1—O11A | 106.3 (5) |
O34iv—Cu6—O31iv | 65.60 (11) | O11B—B1—O11A | 27.3 (9) |
O23—Cu6—Cu4iii | 134.37 (10) | O23—B21—O21 | 114.3 (4) |
O35iii—Cu6—Cu4iii | 41.96 (10) | O23—B21—O24 | 113.3 (4) |
O24vi—Cu6—Cu4iii | 135.01 (10) | O21—B21—O24 | 109.3 (4) |
O34iv—Cu6—Cu4iii | 44.38 (9) | O23—B21—O22 | 112.8 (4) |
O31iv—Cu6—Cu4iii | 81.85 (8) | O21—B21—O22 | 101.0 (4) |
O23—Cu6—Cu7iv | 64.84 (10) | O24—B21—O22 | 105.2 (4) |
O35iii—Cu6—Cu7iv | 120.37 (10) | O25—B22—O26 | 122.5 (5) |
O24vi—Cu6—Cu7iv | 93.13 (9) | O25—B22—O22 | 117.4 (4) |
O34iv—Cu6—Cu7iv | 93.27 (9) | O26—B22—O22 | 120.1 (5) |
O31iv—Cu6—Cu7iv | 39.54 (8) | O33—B31—O31 | 115.1 (4) |
Cu4iii—Cu6—Cu7iv | 121.13 (2) | O33—B31—O34 | 115.6 (4) |
O31—Cu7—O24vi | 92.86 (13) | O31—B31—O34 | 108.1 (4) |
O31—Cu7—O36iii | 169.56 (14) | O33—B31—O32 | 108.7 (4) |
O24vi—Cu7—O36iii | 96.91 (13) | O31—B31—O32 | 101.3 (4) |
O31—Cu7—O41 | 91.16 (13) | O34—B31—O32 | 106.6 (4) |
O24vi—Cu7—O41 | 159.51 (14) | O35—B32—O36 | 122.3 (4) |
O36iii—Cu7—O41 | 78.40 (13) | O35—B32—O32 | 119.6 (4) |
O31—Cu7—Cu6vi | 50.29 (9) | O36—B32—O32 | 118.1 (5) |
O24vi—Cu7—Cu6vi | 86.52 (9) | O11B—O11A—B1 | 76 (2) |
O36iii—Cu7—Cu6vi | 126.53 (9) | O11B—O11A—Cu3 | 80 (2) |
O41—Cu7—Cu6vi | 80.65 (10) | B1—O11A—Cu3 | 132.8 (4) |
O43vii—Cu8—O42 | 94.16 (15) | O11B—O11A—Cu1 | 77 (2) |
O43vii—Cu8—O31 | 163.88 (14) | B1—O11A—Cu1 | 89.6 (3) |
O42—Cu8—O31 | 98.67 (14) | Cu3—O11A—Cu1 | 123.6 (3) |
O43vii—Cu8—O32 | 93.18 (14) | O41—B4—O43 | 125.4 (4) |
O42—Cu8—O32 | 171.42 (13) | O41—B4—O42 | 124.5 (4) |
O31—Cu8—O32 | 73.36 (13) | O43—B4—O42 | 110.1 (4) |
O41—Cu9—O36iii | 81.57 (14) | O41—B4—Cu9vii | 176.5 (4) |
O41—Cu9—O42viii | 102.45 (14) | O43—B4—Cu9vii | 55.2 (2) |
O36iii—Cu9—O42viii | 174.54 (14) | O42—B4—Cu9vii | 54.9 (2) |
O41—Cu9—O43viii | 161.35 (15) | O11A—O11B—B1 | 77 (3) |
O36iii—Cu9—O43viii | 104.50 (14) | O11A—O11B—Cu3 | 80 (2) |
O42viii—Cu9—O43viii | 70.54 (14) | B1—O11B—Cu3 | 132.9 (16) |
O41—Cu9—B4viii | 135.05 (17) | O11A—O11B—Cu1 | 84 (2) |
O36iii—Cu9—B4viii | 139.53 (16) | B1—O11B—Cu1 | 91.4 (13) |
O42viii—Cu9—B4viii | 35.40 (15) | Cu3—O11B—Cu1 | 125.8 (13) |
Symmetry codes: (i) −x, y−1/2, −z+3/2; (ii) −x, y+1/2, −z+3/2; (iii) x, y+1, z; (iv) x, −y+3/2, z+1/2; (v) x, −y+1/2, z+1/2; (vi) x, −y+3/2, z−1/2; (vii) −x+1, y−1/2, −z−1/2; (viii) −x+1, y+1/2, −z−1/2; (ix) x, y−1, z; (x) x, −y+1/2, z−1/2. |
Experimental details
Crystal data | |
Chemical formula | Cu9B6O18 |
Mr | 924.81 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 296 |
a, b, c (Å) | 17.820 (2), 8.5232 (12), 9.1706 (12) |
β (°) | 95.913 (6) |
V (Å3) | 1385.4 (3) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 13.64 |
Crystal size (mm) | 0.20 × 0.20 × 0.15 |
Data collection | |
Diffractometer | Bruker Kappa APEXII CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2004) |
Tmin, Tmax | 0.101, 0.153 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 9748, 3410, 2542 |
Rint | 0.036 |
(sin θ/λ)max (Å−1) | 0.667 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.030, 0.063, 0.96 |
No. of reflections | 3410 |
No. of parameters | 301 |
Δρmax, Δρmin (e Å−3) | 1.11, −0.91 |
Computer programs: APEX2 (Bruker, 2004), SAINT (Bruker, 2004), SHELXTL (Sheldrick, 2008) and BS (Ozawa & Kang, 2004).
Cu1—O11A | 1.956 (5) | Cu7—O41 | 1.995 (3) |
Cu1—O11B | 1.92 (2) | Cu8—O31 | 1.910 (3) |
Cu1—O12i | 1.906 (3) | Cu8—O32 | 1.996 (3) |
Cu1—O13 | 1.896 (4) | Cu8—O42 | 1.898 (3) |
Cu1—O26 | 1.924 (4) | Cu8—O43vii | 1.885 (3) |
Cu2—O12ii | 1.990 (3) | Cu9—O36iii | 1.934 (3) |
Cu2—O21 | 1.925 (3) | Cu9—O41 | 1.926 (3) |
Cu2—O26iii | 2.010 (3) | Cu9—O42viii | 1.961 (3) |
Cu2—O34iv | 1.967 (3) | Cu9—O43viii | 1.969 (3) |
Cu3—O11A | 1.908 (5) | B1—O12 | 1.354 (7) |
Cu3—O11B | 1.91 (2) | B1—O13 | 1.370 (7) |
Cu3—O13ii | 1.850 (4) | B1—O11B | 1.40 (3) |
Cu3—O21 | 1.921 (3) | B1—O11A | 1.405 (8) |
Cu3—O22 | 1.970 (3) | B21—O21 | 1.451 (6) |
Cu4—O25 | 1.903 (3) | B21—O22 | 1.555 (6) |
Cu4—O33 | 1.921 (3) | B21—O23 | 1.422 (6) |
Cu4—O34v | 1.994 (3) | B21—O24 | 1.506 (6) |
Cu4—O35 | 1.916 (3) | B22—O22 | 1.394 (6) |
Cu5—O21vi | 2.324 (3) | B22—O25 | 1.348 (7) |
Cu5—O23 | 1.868 (3) | B22—O26 | 1.355 (6) |
Cu5—O24vi | 2.037 (3) | B31—O31 | 1.465 (6) |
Cu5—O25 | 1.954 (3) | B31—O32 | 1.552 (6) |
Cu5—O33 | 1.874 (3) | B31—O33 | 1.415 (6) |
Cu6—O23 | 1.897 (3) | B31—O34 | 1.505 (6) |
Cu6—O24vi | 2.013 (3) | B32—O32 | 1.415 (6) |
Cu6—O31iv | 2.333 (3) | B32—O35 | 1.355 (6) |
Cu6—O34iv | 2.090 (3) | B32—O36 | 1.359 (6) |
Cu6—O35iii | 1.913 (3) | B4—O41 | 1.349 (6) |
Cu7—O24vi | 1.958 (3) | B4—O42 | 1.389 (6) |
Cu7—O31 | 1.931 (3) | B4—O43 | 1.381 (6) |
Cu7—O36iii | 1.994 (3) |
Symmetry codes: (i) −x, y−1/2, −z+3/2; (ii) −x, y+1/2, −z+3/2; (iii) x, y+1, z; (iv) x, −y+3/2, z+1/2; (v) x, −y+1/2, z+1/2; (vi) x, −y+3/2, z−1/2; (vii) −x+1, y−1/2, −z−1/2; (viii) −x+1, y+1/2, −z−1/2. |
The copper(II) boron oxides CuB2O4 and Cu3B2O6 attract great interest owing to the combination of their structural and unusual physical properties (Sakurai et al., 2002; Saito et al., 2008; Martinez-Ripoll et al., 1971; Behm, 1982). The noncentrosymmetric (I42d) canted antiferromagnet CuB2O4 becomes chiral by application of a static magnetic field (Saito et al., 2008). Its crystal structure consists exclusively of BO4 tetrahedra and CuO4 squares. Antiferromagnetic triclinic Cu3B2O6 can be considered as a two-dimensional spin system because of the pronounced layered character of the crystal structure (Sakurai et al., 2002). Recently, a high-pressure modification of CuB4O7 (Knyrim et al., 2008) with CuII, isotypic with β-ZnB4O7, has been reported, showing BO4 tetrahedra and CuO5 square pyramids. The common feature of all these systems is Jahn–Teller distortion of the Cu coordination polyhedra, due to the electronic configuration of the d9 ion, which can lead to anisotropic character of the crystal structure.
During an investigation of the Li–Cu–B–O system we prepared a new polymorphic modification of Cu3B2O6. A monoclinic crystal structure of Cu3B2O6 was obtained, which can be considered as pseudo-layered with much shorter distances between neighbouring layers (1.505 Å; Fig. 1) than in the triclinic polymorph (2.7 Å; Behm, 1982). The monoclinic structure contains six-layered packing; the layers are parallel to the [402] plane and offset with respect to one another.
There are isolated BO3 triangles and B2O6 units, consisting of corner-shared BO3 triangles and BO4 tetrahedra, in the structure, giving the formula Cu9(BO3)2(B2O6)2, while the other polymorph has only B2O54- and BO33- species and a separate O2- anion, resulting in the composition Cu15[(B2O5)2(BO3)6O2]. The shortest distance between neighbouring layers is 1.506 (6) Å for the B—O bond in the BO4 tetrahedra (Fig. 1). The average B—O length is 1.366 (7) Å in the triangles and 1.483 (6) Å in the tetrahedra. This form of borate anion is quite unusual, but a report on the presence of tetrahedrally and triangularly bonded B atoms in one formation already exists (Rowsell et al., 2002). Almost all of the Cu atoms have nearly planar square coordination environments, with one or two longer contacts to O atoms from neighbouring layers, forming distorted square-pyramidal or octahedral coordination environments. Atoms Cu1 and Cu2 are exceptions, having no additional contacts shorter than 3.1 Å. Each layer contains CuO4 squares and Cu2O6 dimers sharing the corners, and BO3 triangles and B2O5 units, which are surrounded on both sides by infinite CuO2 chains from edge-sharing CuO4 squares (Fig. 2). The CuO2 chains extend parallel to the b axis. The Cu—O bond lengths in the layer vary from 1.868 (3) to 2.088 (4) Å and those between neighbouring layers vary from 2.333 (3) to 2.738 (3) Å, forming CuO5 and CuO6 polyhedra.
It has already been shown (Behm, 1982; Pardo et al., 1974) that other borates (M3B2O6, with M2+ = Mg, Ni and Co) crystallize in a completely different structure type, with only isolated BO3 triangles and practically undistorted MO6 octahedra, which form a three-dimensional network. The peculiarity of Cu3B2O6 structures is probably based on the ability of Cu2+ to adopt different coordination environments as a result of Jahn–Teller distortion.