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Incommensurately modulated borate structures of a new type were studied in detail in the nonlinear optical (NLO) materials Cs2TB4O9 (T = Ge, Si) using single-crystal X-ray diffraction techniques. The structures were solved by the charge-flipping algorithm in the superspace group I2(αβ0)0. The refinement results strongly suggest that the main structure modulation feature of Cs2TB4O9 is the ordering of the O atoms. With these modulated structure models, the unreasonable B—O distances in the average structures were explained as the ordering of BO4 and BO3.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S2052520615019733/bp5081sup1.cif
Contains datablocks global, Cs2GeB4O9, Cs2SiB4O9

fcf

Structure factor file (CIF format) https://doi.org/10.1107/S2052520615019733/bp5081Cs2GeB4O9sup2.fcf
Contains datablock I

fcf

Structure factor file (CIF format) https://doi.org/10.1107/S2052520615019733/bp5081Cs2SiB4O9sup3.fcf
Contains datablock I

pdf

Portable Document Format (PDF) file https://doi.org/10.1107/S2052520615019733/bp5081sup4.pdf
Supporting figures and tables

B-IncStrDB reference: 11442EEvkyY

CCDC references: 1432075; 1432076

Computing details top

For both compounds, data collection: CrysAlis PRO, Agilent Technologies, Version 1.171.37.35 (release 13-08-2014 CrysAlis171 .NET) (compiled Aug 13 2014,18:06:01); cell refinement: CrysAlis PRO, Agilent Technologies, Version 1.171.37.35 (release 13-08-2014 CrysAlis171 .NET) (compiled Aug 13 2014,18:06:01); data reduction: CrysAlis PRO, Agilent Technologies, Version 1.171.37.35 (release 13-08-2014 CrysAlis171 .NET) (compiled Aug 13 2014,18:06:01).

(Cs2GeB4O9) top
Crystal data top
B4Cs2GeO9Z = 2
Mr = 525.6F(000) = 468
Monoclinic, I2(αβ0)0†Dx = 3.800 Mg m3
q = -0.482300a* + 0.119200b*Mo Kα radiation, λ = 0.71073 Å
a = 6.7863 (10) ÅCell parameters from 3052 reflections
b = 6.7914 (10) Åθ = 3.6–29.2°
c = 9.9686 (15) ŵ = 11.17 mm1
β = 90°T = 100 K
V = 459.44 (12) Å30.05 × 0.03 × 0.02 mm
† Symmetry operations: (1) x1, x2, x3, x4; (2) −x1, −x2, x3, −x4; (3) x1+1/2, x2+1/2, x3+1/2, x4; (4) −x1+1/2, −x2+1/2, x3+1/2, −x4.

Data collection top
SuperNova, Dual, Cu at zero, Atlas
diffractometer
4440 independent reflections
Radiation source: X-ray tube3004 reflections with I > 3σ(I)
Mirror monochromatorRint = 0.030
Detector resolution: 10.3503 pixels mm-1θmax = 29.3°, θmin = 3.1°
ω scansh = 99
Absorption correction: multi-scan
CrysAlisPro, Agilent Technologies, Version 1.171.37.35 (release 13-08-2014 CrysAlis171 .NET) (compiled Aug 13 2014,18:06:01) Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm. Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.
k = 87
Tmin = 0.779, Tmax = 1l = 139
7489 measured reflections
Refinement top
Refinement on F6 constraints
R[F2 > 2σ(F2)] = 0.050Weighting scheme based on measured s.u.'s w = 1/(σ2(F) + 0.0001F2)
wR(F2) = 0.065(Δ/σ)max = 0.008
S = 1.69Δρmax = 3.39 e Å3
4440 reflectionsΔρmin = 5.58 e Å3
177 parametersAbsolute structure: 1517 of Friedel pairs used in the refinement
13 restraints
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
Cs1000.00120 (10)0.00767 (17)
Cs20.500.24904 (7)0.0083 (2)
Ge100.50.25095 (17)0.0041 (4)
O5b000.6619 (13)0.0029 (14)*0.5
O5a000.3372 (12)0.0029 (14)*0.5
O10.8417 (8)0.6483 (7)0.1559 (5)0.0068 (11)*
O40.7269 (6)0.3979 (5)0.0047 (8)0.0058 (9)*
O20.3523 (8)0.8399 (7)0.8419 (5)0.0070 (11)*
O30.6055 (6)0.7311 (5)0.9930 (8)0.0062 (9)*
B2a0.1661 (17)0.0615 (16)0.5797 (12)0.003 (2)*0.5
B1a0.0579 (18)0.1663 (16)0.4192 (13)0.004 (2)*0.5
B2b0.227 (2)0.0876 (17)0.5555 (14)0.006 (3)*0.5
B1b0.0886 (19)0.2241 (19)0.4423 (14)0.007 (3)*0.5
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cs10.0053 (3)0.0056 (3)0.0121 (3)0.00035 (19)00
Cs20.0106 (4)0.0092 (4)0.0050 (3)0.0006 (3)00
Ge10.0062 (7)0.0042 (6)0.0020 (6)0.0002 (5)00
Bond lengths (Å) top
AverageMinimumMaximum
B2a—O5b1.45 (9)1.44 (12)1.48 (12)
B2a—O1i1.47 (7)1.46 (8)1.50 (8)
B2a—O4i1.47 (6)1.43 (7)1.51 (7)
B2a—O3ii1.53 (6)1.52 (7)1.54 (7)
B1a—O5a1.45 (10)1.42 (14)1.47 (14)
B1a—O4iii1.53 (8)1.44 (9)1.55 (9)
B1a—O2ii1.47 (7)1.46 (9)1.51 (9)
B1a—O3ii1.46 (8)1.40 (9)1.48 (9)
B2b—O5b1.96 (14)1.96 (14)1.96 (14)
B2b—O1i1.38 (16)1.4 (2)1.4 (2)
B2b—O4i1.35 (9)1.30 (12)1.36 (12)
B2b—O3ii1.39 (13)1.38 (18)1.44 (18)
B1b—O5a1.86 (18)1.86 (18)1.86 (18)
B1b—O4iii1.38 (16)1.4 (2)1.4 (2)
B1b—O2ii1.39 (19)1.4 (3)1.4 (3)
B1b—O3ii1.37 (12)1.35 (16)1.39 (16)
Symmetry codes: (i) x1+1/2, x2+1/2, x3+1/2, x4; (ii) x1+1/2, x2+1/2, x31/2, x4; (iii) x11/2, x21/2, x3+1/2, x4.
(Cs2SiB4O9) top
Crystal data top
B4Cs2O9SiZ = 2
Mr = 481.1F(000) = 432
Monoclinic, I2(αβ0)0†Dx = 3.548 Mg m3
q = -0.478500a* + 0.175300b*Mo Kα radiation, λ = 0.71073 Å
a = 6.7489 (10) ÅCell parameters from 2986 reflections
b = 6.7479 (13) Åθ = 3.5–28.8°
c = 9.8894 (13) ŵ = 8.26 mm1
β = 90°T = 180 K
V = 450.37 (12) Å30.05 × 0.02 × 0.02 mm
† Symmetry operations: (1) x1, x2, x3, x4; (2) −x1, −x2, x3, −x4; (3) x1+1/2, x2+1/2, x3+1/2, x4; (4) −x1+1/2, −x2+1/2, x3+1/2, −x4.

Data collection top
SuperNova, Dual, Cu at zero, Atlas
diffractometer
4933 independent reflections
Radiation source: X-ray tube3155 reflections with I > 3σ(I)
Mirror monochromatorRint = 0.019
Detector resolution: 10.3914 pixels mm-1θmax = 29.1°, θmin = 2.9°
ω scansh = 99
Absorption correction: multi-scan
CrysAlisPro, Agilent Technologies, Version 1.171.37.35 (release 13-08-2014 CrysAlis171 .NET) (compiled Aug 13 2014,18:06:01) Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.
k = 79
Tmin = 0.93, Tmax = 1l = 1313
7483 measured reflections
Refinement top
Refinement on F6 constraints
R[F2 > 2σ(F2)] = 0.036Weighting scheme based on measured s.u.'s w = 1/(σ2(F) + 0.0001F2)
wR(F2) = 0.047(Δ/σ)max = 0.037
S = 1.25Δρmax = 2.57 e Å3
4933 reflectionsΔρmin = 2.47 e Å3
178 parametersAbsolute structure: 2223 of Friedel pairs used in the refinement
14 restraints
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
Cs1000.00139 (7)0.01290 (14)
Cs20.500.24894 (8)0.0196 (3)
Si100.50.2467 (5)0.0043 (8)
O5b000.6640 (10)0.0065 (8)*0.5
O5a000.3347 (10)0.0065 (8)*0.5
O10.8470 (8)0.6289 (8)0.1598 (6)0.0091 (12)*
O40.7229 (7)0.3871 (7)0.0051 (6)0.0099 (10)*
O20.3705 (8)0.8463 (7)0.8405 (6)0.0063 (11)*
O30.6143 (8)0.7262 (7)0.9957 (6)0.0106 (10)*
B2a0.1696 (15)0.0558 (14)0.5840 (10)0.009 (2)*0.5
B1a0.0527 (14)0.1691 (14)0.4188 (10)0.0075 (19)*0.5
B2b0.2264 (14)0.0773 (13)0.5584 (9)0.0066 (18)*0.5
B1b0.0789 (15)0.2286 (16)0.4439 (10)0.010 (2)*0.5
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cs10.0093 (3)0.0109 (2)0.0185 (2)0.0001 (2)00
Cs20.0237 (6)0.0227 (5)0.01224 (17)0.0017 (5)00
Si10.0031 (15)0.0081 (16)0.0018 (6)0.0049 (15)00
Bond lengths (Å) top
AverageMinimumMaximum
B2a—O5b1.44 (9)1.43 (12)1.45 (12)
B2a—O1i1.44 (7)1.42 (8)1.47 (8)
B2a—O4i1.49 (6)1.45 (7)1.52 (7)
B2a—O3ii1.52 (6)1.50 (7)1.54 (7)
B1a—O5a1.46 (10)1.45 (14)1.50 (14)
B1a—O4iii1.51 (7)1.44 (9)1.54 (9)
B1a—O2ii1.47 (7)1.45 (8)1.56 (8)
B1a—O3ii1.47 (7)1.42 (9)1.48 (9)
B2b—O5b1.94 (11)1.94 (11)1.94 (11)
B2b—O1i1.38 (11)1.37 (15)1.38 (15)
B2b—O4i1.36 (5)1.34 (7)1.37 (7)
B2b—O3ii1.37 (8)1.37 (11)1.41 (11)
B1b—O5a1.89 (14)1.89 (14)1.89 (14)
B1b—O4iii1.37 (11)1.34 (16)1.40 (16)
B1b—O2ii1.38 (14)1.4 (2)1.4 (2)
B1b—O3ii1.36 (8)1.35 (11)1.38 (11)
Symmetry codes: (i) x1+1/2, x2+1/2, x3+1/2, x4; (ii) x1+1/2, x2+1/2, x31/2, x4; (iii) x11/2, x21/2, x3+1/2, x4.
 

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