inorganic papers
Acta Cryst.(2007). E63, i111–i112 doi:10.1107/S160053680701210X Zavodniket al. SrTeO
3
i111
Acta Crystallographica Section E Structure Reports Online
ISSN 1600-5368
On the thermal evolution of the crystal
structure of SrTeO
3: the
b
-form at 473 K
Valery E. Zavodnik,aSergey A. Ivanova,band Adam I. Stasha*
a
Karpov Institute of Physical Chemistry, 10, Vorontsovo Pole, 105064 Moscow, Russian Federation, andbMaterials Chemistry, Uppsala University, Box 538, SE-75121, Uppsala, Sweden
Correspondence e-mail: [email protected]
Key indicators
Single-crystal X-ray study
T= 473 K
Mean(e–O) = 0.010 A˚
Rfactor = 0.039
wRfactor = 0.086
Data-to-parameter ratio = 36.3
For details of how these key indicators were automatically derived from the article, see http://journals.iucr.org/e.
Received 27 February 2007 Accepted 14 March 2007
II. The structure of the-phase at 473 K
#2007 International Union of Crystallography All rights reserved
As part of a programme to study structural phase transitions in strontium tellurite, SrTeO3, (STO), the structure of the -form has been determined at 473 K using single-crystal analysis. Both the structural and non-linear optical measure-ments indicate an – first-order phase-transition tempera-ture that is close to 363 K on heating and 308 K on cooling. The structure of the-phase is monoclinic (C2/c) and does not differ essentially from the-phase (C2) configuration. During the–phase transition there is a slight rearrangement of the cation building blocks [n-vertex SrOnpolyhedra (n= 6, 7 or 8)
and TeO3 pyramids]; this phase transformation can be described by a displacive mechanism.
Comment
A number of studies have been undertaken to elucidate the polymorphism of SrTeO3 (STO) (Yamada, 1975; Simon et
al.,1979; Ismailzadeet al., 1979; Libertz & Sadovskaya, 1980, Antonenkoet al., 1982; Kudzinet al., 1988), but so far this has not led to a complete understanding of the structural mechanisms of the observed phase-transition sequence. Recently, in the first paper of the present series (Zavodniket al., 2007), the structure of-phase STO was reported. This article reports the structure of the-phase.
There have been a number of experimental studies on the
[image:1.610.207.458.512.704.2]– phase transition (Ismailzade et al., 1979; Libertz & Sadovskaya, 1980; Kudzinet al., 1988). This phase transition is
Figure 1
The crystal structure of-SrTeO3at 473 K. The sequence of Sr polyhedra
reversible and is attended by anomalies in various physical properties (Kudzinet al., 1982; Sadovskaya, 1984; Antonenko
et al., 1982). The thermal hysteresis, the endo effect on the thermogravimetric curve and the abrupt change of dielectric permittivity are clear indications of a first-order phase tran-sition. At 363 K the SHG signal vanishes, reflecting a transi-tion to the centrosymmetric structure. It was determined by Sadovskaya (1984) and Kudzinet al.(1988) that the–phase transition is connected with the formation and motion of interfaces which are formed by crystallographic planes with indices close to (105) and (501).
The -phase of STO (Fig. 1) forms a three-dimensional network structure, consisting of several types of irregular n -vertex SrOn(n= 6, 7 or 8) polyhedra sharing corners or faces
and TeO3pyramids which share edges with Sr polyhedra but are not connected to each other. A few Te—O bond lengths for Te3, Te5 and Te6 cations are located at distances greater than 2.7 A˚ and do not contribute to the first coordination shell of Te4+. From a comparison of atomic positions in the- and
-phases, it was found that these structures are closely related and we are probably dealing with a displacive transition. Early investigators (Elerman, 1993; Dityatiev et al., 2006) believed that the-phase STO at 300 K was monoclinicC2/c. Current research indicates that thisC2/cstructure was found for the -phase of STO except for minor discrepancies (Elerman’s model did not locate the position of one O atom). The reasons for these discrepancies are not completely clear, and the details of the structural mechanism associated with the –
phase transition will be described later.
Experimental
Single crystals of STO were grown by the Czochralski technique as described earlier (Libertz & Sadovskaya, 1980; Avramenko et al., 1984). The products were characterized in a scanning electron microscope (Jeol 820) with an energy-dispersive spectrometer (LINK AN10000), confirming the presence and stoichiometry of Sr and Te. SHG measurements showed that there is an inversion centre in the -phase, in full agreement with the results of Libertz & Sadovskaya (1980). Following second-harmonic generation (SHG) measurements performed in our research, the-phase is stable between 363 K and 563 K on heating, and between 308 K and 563 K on cooling with a thermal hysteresis.
Crystal data
SrTeO3
Mr= 263.22
Monoclinic,C2=c a= 28.206 (6) A˚
b= 5.921 (1) A˚
c= 28.528 (6) A˚
= 114.16 (3)
V= 4347.1 (15) A˚3
Z= 48 AgKradiation
= 12.13 mm 1
T= 473 (2) K 0.240.220.09 mm
Data collection
Enraf–Nonius CAD-4 diffractometer with high-temperature device Absorption correction: analytical
Alcock, 1970
6672 independent reflections 1757 reflections withI> 2(I)
Rint= 0.090
3 standard reflections frequency: 60 min
Refinement
R[F2> 2(F2)] = 0.039
wR(F2) = 0.086
S= 0.72 6672 reflections
184 parameters
max= 2.99 e A˚ 3
min= 1.97 e A˚ 3
The doubling of the -phase unit cell relative to the -phase (Zavodniket al., 2007) results in a superlattice which can be described by the following transformation matrix (100, 010, 102). The reflection conditions for these superlattice peaks arek+ l = 2n+ 1. The total number of this class of reflections withI> 2(I) is 238, out of 3336 measured ones. At the same time, the increased temperature, which was 473 K, leads to a significant reduction in the intensity of the high-angle reflections. Of the 1913 reflections withgreater than 21, only
173 had intensities greater than 2. It was difficult to refine the O atoms anisotropically because the ratio of statistically reliable reflections to the number of refined parameters was very far from optimal. Several atoms (Te4, Sr6, O12, O42 and O53) are located inside significant voids which are larger than the voids for the rest of the atoms. The same peculiarity was also established for the-STO structure. The highest residual electron-density peak is located 0.86 A˚ from atom Te6 and the deepest hole is located 0.99 A˚ from atom Sr1. Data collection: CAD-4-PC Manual (Enraf–Nonius ,1993); cell refinement:CAD-4-PCManual; data reduction:CAD-4-PCManual; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure:SHELXL97(Sheldrick, 1997); molecular graphics:DIAMOND(Brandenburg, 2005); software used to prepare material for publication:CIFTAB(Sheldrick, 1997) and
SHELXL97.
The authors thank Dr L. Ya. Sadovskaya for the single-crystal preparation and Dr S. Yu. Stefanovich for the SHG measurements. This research was supported by the Russian Foundation for Basic Research (grant 06–03–32449).
References
Alcock, N. W. (1970).Crystallographic Computing, edited by F. R. Ahmed, pp. 271–278. Copenhagen: Munksgaard.
Antonenko, A. N., Kudzin, A. Yu. & Sadovskaya, L. Ya. (1982).Neorg. Mater.
18, 1213–1216. (In Russian.)
Avramenko, V. P., Kudzin, A. Yu. & Sadovskaya, L. Ya. (1984).Solid State Phys.26, 359–360.
Brandenburg, K. (2005).DIAMOND. Version 3.1. Crystal Impact GbR, Bonn, Germany.
Dityatiev, O. A., Berdonosov, P. S., Dolgikh, V. A., Aldous, D. W. & Lightfoot, P. (2006).Solid State Sci.8, 830–835.
Elerman, Y. (1993).Turk. J. Phys.17, 465–473.
Enraf–Nonius (1993).CAD-4-PC Manual. Version 1.2. Enraf–Nonius, Delft, The Netherlands.
Ismailzade, I. H., Kudzin, A. Yu. & Sadovskaya, L. Ya. (1979).Phys. Status Solidi A,52, K105–109.
Kudzin, A. Yu., Moiseenko, N. V. & Sadovskaya, L. Ya. (1982).Solid State Phys.24, 2837–2839.
Kudzin, A. Yu., Pasalskii, V. M., Polesya, A. F. & Sadovskaya, L. Ya. (1988).
Ukr. Fiz. Zh.33, 251–253. (In Russian.)
Libertz, G. V. & Sadovskaya, L. Ya. (1980).Phys. Status Solidi A,62, K167– 168.
Sadovskaya, L. Ya. (1984). Thesis, Dnepropetrovsk University, Russia. Sheldrick, G. M. (1997).SHELXS97,SHELXL97andCIFTAB. Release 97-2.
University of Go¨ttingen, Germany.
supporting information
sup-1
Acta Cryst. (2007). E63, i111–i112
supporting information
Acta Cryst. (2007). E63, i111–i112 [https://doi.org/10.1107/S160053680701210X]
On the thermal evolution of the crystal structure of SrTeO
3: the
β
-form at 473
K
Valery E. Zavodnik, Sergey A. Ivanov and Adam I. Stash
strontium tellurite
Crystal data
SrTeO3 Mr = 263.22 Monoclinic, C2/c
Hall symbol: -C 2yc
a = 28.206 (6) Å
b = 5.921 (1) Å
c = 28.528 (6) Å
β = 114.16 (3)°
V = 4347.1 (15) Å3 Z = 48
F(000) = 5472
Dx = 4.826 Mg m−3
Ag Kα radiation, λ = 0.56086 Å Cell parameters from 24 reflections
θ = 12.4–14.7°
µ = 12.13 mm−1 T = 473 K Prism, colourless 0.24 × 0.22 × 0.09 mm
Data collection
Enraf–Nonius CAD-4 with high-temperature device
diffractometer
Radiation source: fine-focus sealed tube
β-filter monochromator
ω/2θ scans
Absorption correction: analytical Alcock, 1970
Tmin = 0.139, Tmax = 0.386 6803 measured reflections
6672 independent reflections 1757 reflections with I > 2σ(I)
Rint = 0.090
θmax = 24.0°, θmin = 2.1° h = −36→36
k = 0→8
l = 0→36
3 standard reflections every 60 min intensity decay: none
Refinement
Refinement on F2
Least-squares matrix: full
R[F2 > 2σ(F2)] = 0.039 wR(F2) = 0.086 S = 0.72 6672 reflections 184 parameters 0 restraints
Primary atom site location: structure-invariant direct methods
Secondary atom site location: difference Fourier map
w = 1/[σ2(Fo2) + (0.0358P)2]
(Δ/σ)max = 0.001
Δρmax = 2.99 e Å−3
Δρmin = −1.97 e Å−3
Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Special details
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)
x y z Uiso*/Ueq
Te1 0.15574 (2) 0.2512 (2) 0.42644 (2) 0.02470 (15) Te2 0.41620 (3) 0.27143 (19) 0.17278 (3) 0.02222 (17) Te3 0.27695 (2) 0.2585 (2) 0.14025 (2) 0.01944 (14) Te4 0.00976 (3) 0.2660 (2) 0.11457 (3) 0.03163 (18) Te5 0.39888 (3) 0.25554 (18) 0.00100 (2) 0.02630 (15) Te6 0.30293 (3) 0.2678 (2) 0.29153 (2) 0.01769 (15) Sr1 0.16327 (3) 0.2537 (3) 0.28905 (3) 0.02105 (17) Sr2 0.44114 (4) 0.2802 (2) 0.44539 (3) 0.0223 (2) Sr3 0.14637 (4) 0.2758 (2) 0.13753 (3) 0.0289 (2) Sr4 0.42967 (3) 0.2404 (3) 0.30280 (3) 0.0239 (2) Sr5 0.29752 (3) 0.2539 (3) 0.42372 (3) 0.02285 (18)
Sr6 0.2500 0.2500 0.0000 0.0299 (3)
Sr7 0.0000 0.2184 (3) 0.2500 0.0256 (4)
O11 0.1947 (3) 0.2012 (17) 0.3885 (3) 0.044 (2)*
O12 0.1722 (5) 0.543 (2) 0.4450 (4) 0.065 (3)*
O13 0.1948 (4) 0.1051 (16) 0.4873 (3) 0.040 (2)* O21 0.4073 (4) 0.4764 (14) 0.2179 (3) 0.031 (2)* O22 0.4840 (4) 0.3537 (17) 0.1869 (3) 0.045 (2)* O23 0.4205 (4) 0.0166 (17) 0.2119 (4) 0.044 (3)* O31 0.2278 (3) 0.3094 (15) 0.0746 (3) 0.037 (2)* O32 0.2442 (4) 0.0133 (16) 0.1555 (4) 0.040 (2)* O33 0.2551 (4) 0.4745 (16) 0.1724 (4) 0.040 (2)* O41 0.0555 (4) 0.4824 (15) 0.1117 (4) 0.035 (2)*
O42 0.0251 (5) 0.337 (2) 0.1799 (4) 0.070 (3)*
O43 0.0541 (4) 0.0238 (15) 0.1243 (3) 0.030 (2)* O51 0.3718 (3) 0.4512 (14) −0.0558 (3) 0.0264 (17)* O52 0.3829 (4) −0.0132 (15) −0.0347 (3) 0.035 (2)*
O53 0.4672 (5) 0.309 (2) 0.0082 (4) 0.077 (4)*
O61 0.3435 (3) 0.2248 (15) 0.3616 (2) 0.0287 (16)* O62 0.3410 (3) 0.5148 (13) 0.2862 (3) 0.0234 (17)* O63 0.3394 (4) 0.0479 (15) 0.2729 (3) 0.030 (2)*
Atomic displacement parameters (Å2)
U11 U22 U33 U12 U13 U23
supporting information
sup-3
Acta Cryst. (2007). E63, i111–i112
Te2 0.0194 (3) 0.0236 (4) 0.0259 (3) −0.0025 (5) 0.0116 (2) −0.0021 (5) Te3 0.0157 (3) 0.0187 (3) 0.0244 (3) −0.0010 (6) 0.0088 (2) −0.0045 (6) Te4 0.0227 (4) 0.0223 (4) 0.0551 (4) −0.0017 (6) 0.0212 (3) −0.0042 (5) Te5 0.0327 (4) 0.0253 (4) 0.0250 (3) −0.0029 (6) 0.0159 (3) 0.0002 (5) Te6 0.0166 (3) 0.0175 (4) 0.0206 (2) 0.0009 (5) 0.0094 (2) −0.0009 (4) Sr1 0.0276 (4) 0.0166 (4) 0.0226 (4) −0.0016 (8) 0.0140 (3) 0.0004 (8) Sr2 0.0196 (4) 0.0204 (6) 0.0299 (4) 0.0002 (5) 0.0133 (3) −0.0014 (5) Sr3 0.0331 (5) 0.0269 (6) 0.0255 (4) 0.0036 (7) 0.0109 (4) 0.0003 (5) Sr4 0.0234 (4) 0.0243 (5) 0.0273 (4) −0.0043 (8) 0.0138 (3) 0.0001 (7) Sr5 0.0215 (4) 0.0253 (5) 0.0244 (4) 0.0033 (10) 0.0121 (3) 0.0028 (8) Sr6 0.0400 (7) 0.0292 (8) 0.0283 (6) −0.0043 (15) 0.0220 (5) −0.0009 (13) Sr7 0.0284 (7) 0.0225 (9) 0.0354 (6) 0.000 0.0227 (5) 0.000
Geometric parameters (Å, º)
Te1—O12 1.813 (12) Sr3—O43 2.887 (10)
Te1—O13 1.846 (9) Sr3—O63i 2.907 (9)
Te1—O11 1.855 (9) Sr3—O32 3.023 (11)
Te2—O23 1.850 (10) Sr3—O33 3.047 (11)
Te2—O22 1.850 (10) Sr3—O52vi 3.045 (9)
Te2—O21 1.859 (9) Sr3—O61ii 3.274 (9)
Te3—O33 1.821 (10) Sr4—O22iii 2.425 (10)
Te3—O31 1.843 (8) Sr4—O43i 2.563 (9)
Te3—O32 1.866 (10) Sr4—O63 2.594 (10)
Te4—O42 1.783 (11) Sr4—O21 2.640 (9)
Te4—O41 1.844 (10) Sr4—O42ii 2.658 (13)
Te4—O43 1.848 (9) Sr4—O41ii 2.761 (9)
Te5—O52 1.844 (9) Sr4—O23 2.829 (10)
Te5—O51 1.881 (8) Sr4—O62 2.856 (9)
Te5—O53 1.878 (13) Sr5—O32i 2.584 (10)
Te6—O62 1.856 (8) Sr5—O61 2.596 (6)
Te6—O63 1.867 (9) Sr5—O13vii 2.597 (9)
Te6—O61 1.869 (6) Sr5—O51v 2.603 (9)
Sr1—O63i 2.460 (9) Sr5—O52iv 2.626 (9)
Sr1—O21ii 2.525 (10) Sr5—O11 2.671 (9)
Sr1—O62ii 2.534 (8) Sr5—O31ii 2.733 (9)
Sr1—O11 2.621 (8) Sr5—O33ii 3.020 (10)
Sr1—O33ii 2.678 (10) Sr6—O12ii 2.440 (12)
Sr1—O23i 2.820 (11) Sr6—O12viii 2.440 (12)
Sr1—O32i 2.879 (11) Sr6—O31 2.476 (8)
Sr2—O53iii 2.381 (13) Sr6—O31vi 2.476 (8)
Sr2—O41ii 2.428 (9) Sr6—O13ix 2.552 (10)
Sr2—O43i 2.505 (9) Sr6—O13i 2.552 (10)
Sr2—O52iv 2.506 (9) Sr7—O42x 2.479 (12)
Sr2—O51v 2.510 (8) Sr7—O42 2.479 (12)
Sr2—O61 2.832 (7) Sr7—O23i 2.709 (11)
Sr2—O53v 2.932 (14) Sr7—O23xi 2.709 (11)
Sr3—O62ii 2.571 (8) Sr7—O22xii 2.728 (10)
Sr3—O41 2.657 (11) Sr7—O21xii 2.787 (9)
Sr3—O61i 2.673 (9) Sr7—O21ii 2.787 (9)
O12—Te1—O13 100.9 (5) O32i—Sr5—O31ii 124.0 (3)
O12—Te1—O11 100.4 (5) O61—Sr5—O31ii 99.0 (3)
O13—Te1—O11 101.8 (4) O13vii—Sr5—O31ii 102.1 (3)
O23—Te2—O22 106.1 (5) O51v—Sr5—O31ii 146.5 (3)
O23—Te2—O21 96.3 (4) O52iv—Sr5—O31ii 70.6 (3)
O22—Te2—O21 95.6 (4) O11—Sr5—O31ii 69.1 (3)
O33—Te3—O31 97.3 (4) O32i—Sr5—O33ii 69.7 (3)
O33—Te3—O32 97.3 (4) O61—Sr5—O33ii 62.7 (3)
O31—Te3—O32 97.3 (4) O13vii—Sr5—O33ii 151.3 (3)
O42—Te4—O41 90.5 (5) O51v—Sr5—O33ii 128.5 (3)
O42—Te4—O43 99.5 (5) O52iv—Sr5—O33ii 97.6 (3)
O41—Te4—O43 95.9 (4) O11—Sr5—O33ii 62.6 (3)
O62—Te6—O63 97.0 (4) O31ii—Sr5—O33ii 56.9 (2)
O62—Te6—O61 94.2 (4) O12ii—Sr6—O12viii 180.0 (10)
O63—Te6—O61 92.4 (4) O12ii—Sr6—O31 89.8 (4)
O63i—Sr1—O21ii 127.8 (3) O12viii—Sr6—O31 90.2 (4)
O63i—Sr1—O62ii 79.0 (3) O12ii—Sr6—O31vi 90.2 (4)
O21ii—Sr1—O62ii 79.0 (3) O12viii—Sr6—O31vi 89.8 (4)
O63i—Sr1—O11 139.4 (3) O31—Sr6—O31vi 180.0 (3)
O21ii—Sr1—O11 85.1 (3) O12ii—Sr6—O13ix 90.8 (4)
O62ii—Sr1—O11 136.8 (3) O12viii—Sr6—O13ix 89.2 (4)
O63i—Sr1—O33ii 120.1 (3) O31—Sr6—O13ix 83.4 (3)
O21ii—Sr1—O33ii 98.5 (3) O31vi—Sr6—O13ix 96.6 (3)
O62ii—Sr1—O33ii 74.8 (3) O12ii—Sr6—O13i 89.2 (4)
O11—Sr1—O33ii 68.2 (3) O12viii—Sr6—O13i 90.8 (4)
O63i—Sr1—O23i 79.8 (3) O31—Sr6—O13i 96.6 (3)
O21ii—Sr1—O23i 74.2 (3) O31vi—Sr6—O13i 83.4 (3)
O62ii—Sr1—O23i 123.5 (3) O13ix—Sr6—O13i 180.0 (5)
O11—Sr1—O23i 89.2 (3) O42x—Sr7—O42 147.1 (6)
O33ii—Sr1—O23i 157.0 (3) O42x—Sr7—O23i 87.4 (4)
O63i—Sr1—O32i 76.8 (3) O42—Sr7—O23i 71.1 (4)
O21ii—Sr1—O32i 153.9 (3) O42x—Sr7—O23xi 71.1 (4)
O62ii—Sr1—O32i 118.8 (3) O42—Sr7—O23xi 87.4 (4)
O11—Sr1—O32i 68.9 (3) O23i—Sr7—O23xi 98.6 (5)
O33ii—Sr1—O32i 70.8 (3) O42x—Sr7—O22ii 73.5 (4)
O23i—Sr1—O32i 106.1 (3) O42—Sr7—O22ii 137.0 (3)
O53iii—Sr2—O41ii 95.3 (4) O23i—Sr7—O22ii 111.4 (3)
O53iii—Sr2—O43i 90.1 (4) O23xi—Sr7—O22ii 131.9 (3)
O41ii—Sr2—O43i 81.7 (3) O42x—Sr7—O22xii 137.0 (3)
O53iii—Sr2—O52iv 125.7 (4) O42—Sr7—O22xii 73.5 (4)
O41ii—Sr2—O52iv 84.4 (3) O23i—Sr7—O22xii 131.9 (3)
O43i—Sr2—O52iv 142.7 (3) O23xi—Sr7—O22xii 111.4 (3)
O53iii—Sr2—O51v 128.7 (4) O22ii—Sr7—O22xii 75.4 (4)
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Acta Cryst. (2007). E63, i111–i112
O43i—Sr2—O51v 85.3 (3) O42—Sr7—O21xii 114.8 (3)
O52iv—Sr2—O51v 79.8 (3) O23i—Sr7—O21xii 168.1 (3)
O53iii—Sr2—O61 159.6 (3) O23xi—Sr7—O21xii 72.1 (3)
O41ii—Sr2—O61 69.0 (3) O22ii—Sr7—O21xii 71.9 (3)
O43i—Sr2—O61 75.3 (3) O22xii—Sr7—O21xii 59.8 (3)
O52iv—Sr2—O61 67.5 (3) O42x—Sr7—O21ii 114.8 (3)
O51v—Sr2—O61 65.1 (2) O42—Sr7—O21ii 82.6 (3)
O53iii—Sr2—O53v 70.0 (5) O23i—Sr7—O21ii 72.1 (3)
O41ii—Sr2—O53v 160.8 (4) O23xi—Sr7—O21ii 168.1 (3)
O43i—Sr2—O53v 85.8 (3) O22ii—Sr7—O21ii 59.8 (3)
O52iv—Sr2—O53v 114.1 (3) O22xii—Sr7—O21ii 71.9 (3)
O51v—Sr2—O53v 58.8 (3) O21xii—Sr7—O21ii 118.1 (4)
O61—Sr2—O53v 121.7 (3) Te1—O11—Sr1 126.4 (4)
O51vi—Sr3—O62ii 111.2 (3) Te1—O11—Sr5 125.0 (4)
O51vi—Sr3—O41 100.3 (3) Sr1—O11—Sr5 103.1 (3)
O62ii—Sr3—O41 107.2 (3) Te1—O12—Sr6i 136.2 (6)
O51vi—Sr3—O61i 120.9 (2) Te1—O13—Sr6ii 127.9 (4)
O62ii—Sr3—O61i 127.8 (2) Te1—O13—Sr5vii 123.2 (5)
O41—Sr3—O61i 68.4 (3) Sr6ii—O13—Sr5vii 108.9 (3)
O51vi—Sr3—O43 77.0 (3) Te2—O21—Sr1i 134.1 (4)
O62ii—Sr3—O43 66.8 (3) Te2—O21—Sr4 103.9 (4)
O41—Sr3—O43 59.1 (2) Sr1i—O21—Sr4 107.5 (3)
O61i—Sr3—O43 127.0 (2) Te2—O21—Sr7xiii 100.9 (4)
O51vi—Sr3—O63i 176.3 (3) Sr1i—O21—Sr7xiii 107.2 (3)
O62ii—Sr3—O63i 70.6 (2) Sr4—O21—Sr7xiii 97.5 (3)
O41—Sr3—O63i 76.1 (3) Te2—O22—Sr4iii 148.3 (5)
O61i—Sr3—O63i 57.6 (2) Te2—O22—Sr7xiii 103.2 (4)
O43—Sr3—O63i 101.2 (3) Sr4iii—O22—Sr7xiii 104.6 (3)
O51vi—Sr3—O32 73.3 (3) Te2—O23—Sr7xiv 127.8 (6)
O62ii—Sr3—O32 75.3 (3) Te2—O23—Sr1ii 126.6 (5)
O41—Sr3—O32 173.6 (3) Sr7xiv—O23—Sr1ii 101.3 (3)
O61i—Sr3—O32 115.0 (2) Te2—O23—Sr4 97.5 (4)
O43—Sr3—O32 117.9 (3) Sr7xiv—O23—Sr4 100.8 (3)
O63i—Sr3—O32 110.4 (3) Sr1ii—O23—Sr4 91.7 (3)
O51vi—Sr3—O33 107.4 (3) Te3—O31—Sr6 120.0 (4)
O62ii—Sr3—O33 100.6 (3) Te3—O31—Sr5i 103.5 (3)
O41—Sr3—O33 129.8 (3) Sr6—O31—Sr5i 108.2 (3)
O61i—Sr3—O33 61.5 (2) Te3—O32—Sr5ii 110.5 (4)
O43—Sr3—O33 167.2 (3) Te3—O32—Sr1ii 96.9 (4)
O63i—Sr3—O33 75.0 (3) Sr5ii—O32—Sr1ii 98.6 (3)
O32—Sr3—O33 54.3 (3) Te3—O32—Sr3 93.7 (4)
O51vi—Sr3—O52vi 59.3 (2) Sr5ii—O32—Sr3 95.7 (3)
O62ii—Sr3—O52vi 168.8 (3) Sr1ii—O32—Sr3 158.0 (4)
O41—Sr3—O52vi 70.7 (3) Te3—O33—Sr1i 103.3 (5)
O61i—Sr3—O52vi 62.4 (2) Te3—O33—Sr5i 94.0 (4)
O43—Sr3—O52vi 103.8 (3) Sr1i—O33—Sr5i 93.2 (3)
O63i—Sr3—O52vi 118.4 (2) Te3—O33—Sr3 93.9 (4)
O33—Sr3—O52vi 88.6 (3) Sr5i—O33—Sr3 82.0 (3)
O51vi—Sr3—O61ii 57.8 (2) Te4—O41—Sr2i 139.0 (5)
O62ii—Sr3—O61ii 54.0 (2) Te4—O41—Sr3 106.3 (4)
O41—Sr3—O61ii 122.1 (2) Sr2i—O41—Sr3 102.9 (4)
O61i—Sr3—O61ii 169.2 (3) Te4—O41—Sr4i 101.6 (4)
O43—Sr3—O61ii 63.7 (2) Sr2i—O41—Sr4i 99.0 (3)
O63i—Sr3—O61ii 124.4 (2) Sr3—O41—Sr4i 103.3 (3)
O32—Sr3—O61ii 54.2 (2) Te4—O42—Sr7 138.5 (7)
O33—Sr3—O61ii 108.0 (2) Te4—O42—Sr4i 107.3 (5)
O52vi—Sr3—O61ii 117.1 (2) Sr7—O42—Sr4i 112.3 (4)
O22iii—Sr4—O43i 83.3 (3) Te4—O43—Sr2ii 125.5 (4)
O22iii—Sr4—O63 164.4 (3) Te4—O43—Sr4ii 121.0 (4)
O43i—Sr4—O63 112.3 (3) Sr2ii—O43—Sr4ii 102.5 (3)
O22iii—Sr4—O21 79.4 (3) Te4—O43—Sr3 97.9 (3)
O43i—Sr4—O21 107.1 (3) Sr2ii—O43—Sr3 93.6 (3)
O63—Sr4—O21 95.6 (3) Sr4ii—O43—Sr3 112.4 (3)
O22iii—Sr4—O42ii 81.0 (4) Te5—O51—Sr2viii 109.8 (4)
O43i—Sr4—O42ii 121.7 (3) Te5—O51—Sr3vi 108.7 (4)
O63—Sr4—O42ii 89.9 (3) Sr2viii—O51—Sr3vi 102.1 (3)
O21—Sr4—O42ii 124.2 (3) Te5—O51—Sr5viii 127.7 (4)
O22iii—Sr4—O41ii 105.3 (3) Sr2viii—O51—Sr5viii 97.4 (3)
O43i—Sr4—O41ii 74.5 (3) Sr3vi—O51—Sr5viii 107.8 (3)
O63—Sr4—O41ii 79.7 (3) Te5—O52—Sr2ix 129.4 (5)
O21—Sr4—O41ii 175.2 (3) Te5—O52—Sr5ix 133.6 (5)
O42ii—Sr4—O41ii 56.7 (3) Sr2ix—O52—Sr5ix 96.9 (3)
O22iii—Sr4—O23 87.2 (3) Te5—O52—Sr3vi 92.4 (3)
O43i—Sr4—O23 165.8 (3) Sr2ix—O52—Sr3vi 91.0 (3)
O63—Sr4—O23 77.5 (3) Sr5ix—O52—Sr3vi 88.8 (3)
O21—Sr4—O23 60.6 (3) Te5—O53—Sr2iii 151.8 (6)
O42ii—Sr4—O23 66.8 (3) Te5—O53—Sr2viii 94.8 (5)
O41ii—Sr4—O23 118.4 (3) Sr2iii—O53—Sr2viii 110.0 (5)
O22iii—Sr4—O62 129.1 (3) Te6—O61—Sr5 117.6 (3)
O43i—Sr4—O62 67.4 (3) Te6—O61—Sr3ii 99.3 (3)
O63—Sr4—O62 61.3 (2) Sr5—O61—Sr3ii 98.1 (3)
O21—Sr4—O62 71.5 (3) Te6—O61—Sr2 147.7 (4)
O42ii—Sr4—O62 149.7 (3) Sr5—O61—Sr2 90.03 (18)
O41ii—Sr4—O62 105.4 (3) Sr3ii—O61—Sr2 92.5 (2)
O23—Sr4—O62 111.7 (3) Te6—O61—Sr3i 83.5 (3)
O32i—Sr5—O61 67.5 (3) Sr5—O61—Sr3i 89.7 (2)
O32i—Sr5—O13vii 119.4 (3) Sr3ii—O61—Sr3i 169.2 (3)
O61—Sr5—O13vii 145.5 (3) Sr2—O61—Sr3i 80.0 (2)
O32i—Sr5—O51v 80.5 (3) Te6—O62—Sr1i 132.9 (4)
O61—Sr5—O51v 67.5 (3) Te6—O62—Sr3i 106.8 (3)
O13vii—Sr5—O51v 80.1 (3) Sr1i—O62—Sr3i 108.9 (3)
O32i—Sr5—O52iv 136.3 (3) Te6—O62—Sr4 92.0 (3)
O61—Sr5—O52iv 69.5 (3) Sr1i—O62—Sr4 101.1 (3)
O13vii—Sr5—O52iv 92.3 (3) Sr3i—O62—Sr4 113.2 (3)
supporting information
sup-7
Acta Cryst. (2007). E63, i111–i112
O32i—Sr5—O11 72.8 (3) Te6—O63—Sr4 100.4 (4)
O61—Sr5—O11 120.3 (2) Sr1ii—O63—Sr4 106.6 (3)
O13vii—Sr5—O11 92.8 (3) Te6—O63—Sr3ii 91.7 (3)
O51v—Sr5—O11 144.4 (3) Sr1ii—O63—Sr3ii 101.0 (3)
O52iv—Sr5—O11 139.5 (3) Sr4—O63—Sr3ii 101.0 (3)
