Crystal structures of the triple perovskites Ba2K2Te2O9 and Ba2KNaTe2O9, and redetermination of the double perovskite Ba2CaTeO6.

Single crystals of Ba2K2Te2O9 (dibarium dipotassium nona-oxidoditellurate), (I), Ba2KNaTe2O9 (dibarium potassium sodium nona-oxidoditellurate), (II), and Ba2CaTeO6 (dibarium calcium hexa-oxidotellurate), (III), were obtained from KNO3/KI or KNO3/NaNO3 flux syntheses in platinum crucibles for (I) and (II), or porcelain crucibles for (III). (I) and (II) are isotypic and are members of triple perovskites with general formula A2[12co]A'[12co]B2[6o]B'[6o]O9. They crystallize in the 6H-BaTiO3 structure family in space-group type P63/mmc, with the A, A', B and B' sites being occupied by K, Ba, Te and a second Ba in (I), and in (II) by mixed-occupied (Ba/K), Ba, Te and Na sites, respectively. (III) adopts the A2[12co]B'[6o]B''[6o]O6 double perovskite structure in space-group type Fmm, with Ba, Ca and Te located on the A, B' and B'' sites, respectively. The current refinement of (III) is based on single-crystal X-ray data. It confirms the previous refinement from X-ray powder diffraction data [Fu et al. (2008). J. Solid State Chem.181, 2523-2529], but with higher precision.

Chemical context

During a recent project on the structure determination of barium oxotellurates(VI), different preparation methods were applied for single-crystal growth of the phases Ba[H4TeO6], Ba[H2TeO5], Ba[Te2O6(OH)2] and Ba[TeO4] (Weil et al., 2016 ▸). Owing to the different water content that defines the thermal stability range of the respective phase, relatively mild temperatures < 600 K had to be adjusted for the three hydrous phases using either a diffusion method in aqueous solutions (room temperature) or hydro­thermal methods (ca 470 K), whereas for the anhydrous phase higher temperatures could be employed. However, Ba[TeO4] decomposes into Ba[TeO3] with release of oxygen at temperatures above 1000 K, which prevents prolonged heating near this temperature. Although very small crystals of Ba[TeO4] with a rather poor quality could eventually be grown by heating Ba[H4TeO6] at 873 K for some days (Weil et al., 2016 ▸), alternative crystal-growth methods were tested with the intention of obtaining larger crystals with better quality. With the upper stability range of the target phase Ba[TeO4] in mind, KNO3/KI or KNO3/NaNO3 mixtures were used for crystal-growth experiments. Such salt mixtures have low eutectic melting points, e.g. 498 K for a 50:50 mol% mixture of NaNO3/KNO3 (Berg & Kerridge, 2004 ▸). At least for the latter eutectic mixture, crystal-growth experiments from the melt have already been applied successfully for another barium phase, viz. Ba2As2O7 (Weil, 2016 ▸). However, Ba[TeO4] did not form under the given conditions because K+ or mixtures of K+ and Na+ were incorporated instead, resulting in the formation of Ba2K2Te2O9 (I) or Ba2KNaTe2O9 (II) single crystals. In the case a porcelain crucible was employed, Ba2CaTeO6 (III) was obtained in form of very few single crystals.

Structural commentary

The three title compounds belong to the vast family of perovskites (Tilley, 2016 ▸). The ideal cubic A [12 B [6O3 perovskite structure comprises of corner-sharing [BO6] octa­hedra. In the centre of the resulting 3 ∞[BO6/2] network, the A-site cation occupies a 12-coordinate cubocta­hedral site. The 2H hexa­gonal perovskite structure contains chains of face-sharing [BO6] octa­hedra that are separated by chains of A-site cations. In an alternative description, perovskite structures can be derived from closed-packed arrangements of the anions with different stacking sequences (Lufaso & zur Loye, 2005a ▸; Stöger et al., 2010 ▸). For example, in the cubic perovskite an ABC stacking and in the hexa­gonal 2H perovskite an AB stacking is observed. More complex structures that are realized in double perovskites or triple perovskites can include both cubic (c) and hexa­gonal stacking sequences (h) and consequently structure motifs of corner-sharing and face-sharing [BO6] octa­hedra like in the triple perovskites discussed below.

Ba2K2Te2O9 (I) and Ba2KNaTe2O9 (II) are isotypic and members of the triple perovskite family with general formula A 2 [12 A′[12 B 2 [6 B′[6O9. They crystallize in the 6H-BaTiO3 structure type in space-group type P63 /mmc with Z = 2. In (I) the A, A′, B and B′ sites are occupied by K1, Ba1, Te1 and Ba2, and in (II) by mixed-occupied (Ba/K)1, Ba1, Te1 and Na2, respectively. The 6H-BaTiO3 structure type is sometimes also referred to as the BaFeO2+ structure type with possible values for Z = 2, 3 or 6, dependent on the overall formula sum of the compound. The stacking sequence for this structure type is (cch)2 (Tilley, 2016 ▸). About 240 entries of this structure family are compiled in the recent version of the Inorganic Crystal Structure Database (ICSD, 2018 ▸), with hexa­gonal BaTiO3 being the first phase that has been structurally determined (Burbank & Evans, 1948 ▸). Only four Te-containing phases have been reported so far to adopt this structure type, viz. Ba3Fe2TeO9 (Harari et al., 1972 ▸), K3LaTe2O9 (Zhang et al., 2015 ▸), Ba3Cr1.94Te1.06O9 (Li et al., 2016 ▸) and the high-pressure phase Ba2NiTeO6 (Z = 3; Aoba et al., 2016 ▸). A review of this structure type and of perovskites in general was given recently by Tilley (2016 ▸). In both structures (I) and (II), Ba1 is situated on Wyckoff position 2b (site symmetry m2), the K1 site in (I) and the mixed-occpied (Ba/K)1 site (occupancy ratio 1:1) in (II) on 4f (3m.), Ba2 in (I) and Na2 in (II) on 2a ( m.), and in both structures Te1 4f (3m.), O1 on 6h (mm2) and O2 on 12k (.m.), respectively. Hence the smaller TeVI atoms occupy the face-sharing octa­hedral B site while the larger barium (Ba2 in (I)) or sodium cations (Na2 in (II)) occupy the corner-sharing octa­hedral B′ site. The inner angles of the two face-sharing [TeO6] octa­hedra in (I) and (II) (Table 1 ▸) are more similar than those in isotypic triple perovskites (Lufaso & zur Loye, 2005a ▸), with center shifts of 0.076 Å in (I) and of 0.191 Å in (II). Representative for both (I) and (II), the crystal structure of Ba2K2Te2O9 is given in Fig. 1 ▸. It should be noted that the A (= K1) position in (I) has only nine coordination partners, while in (II) twelve oxygen atoms surround the corresponding site that is statistically occupied by Ba2+ and K+ (= (Ba/K)1).

Table 1

Selected bond lengths (Å) and angles (°) in the structures (I)–(III)

(I)		(II)		(III)
K1—O1	2.893 (2) [3×]	(Ba/K)1—O2	2.98780 (19) [6×]	Ba—O	2.9577 (5) [12×]
K1—O2	3.0359 (17) [6×]	(Ba/K)1—O2	3.1064 (19) [3×]	Ca—O	2.247 (3) [6x]
		(Ba/K)1—O1	3.1927 (12) [3×]	Te—O	1.930 (3) [6×]
Ba1—O2	2.952 (2) [6×]	Ba1—O2	2.9532 (18) [6×]
Ba1—O1	3.0382 (17) [6×]	Ba1—O1	2.9935 (14) [6×]
Te1—O2	1.8524 (18) [3×]	Te1—O2	1.8481 (16) [3×]
Te1—O1	2.0474 (16) [3×]	Te1—O1	2.0418 (14) [3×]
Ba2—O2	2.5910 (18) [6×]	Na2—O2	2.3037 (16) [6×]
O1—Te1—O1	75.43 (7) [3×]	O1—Te1—O1	75.95 (6) [3×]
Δa	0.076	Δa	0.191

Note: (a) Δ is the center shift (Å) of the Te atoms in the Te2O9 dimer. The center shift is defined as the distance between the Te atoms in the 4f Wyckoff position (z ≃ 1/6) of the actual crystal structure and the ideal high-symmetry 4f Te position (z = 1/6) (Lufaso & zur Loye, 2005a ▸).

Figure 1

Projection of the crystal structure of Ba2K2Te2O9 (I) along [00]. [Ba2O6] octa­hedra are green, [TeO6] octa­hedra are red, potassium sites are blue, Ba1 sites turquoise and O sites shaded pale grey. Displacement ellipsoids are drawn at the 97% probability level.

The current refinement of Ba2CaTeO6 (III) is based on single crystal X-ray data and confirms the previous structure determination from X-ray powder diffraction data, but with higher precision (reliability factors for the previous deter­min­ation: R wp = 0.159, R p = 0.112; Fu et al., 2008 ▸). Ba2CaTeO6 (III) is a member of the double perovskite family with general formula A 2 [12 B′ [6 B′′ [6O6. Dependent on the cations present at the B′ and B′′ sites, double perovskites are functional oxide materials with inter­esting electronic and magnetic properties (Vasala & Karppinen, 2015 ▸). In the crystal structure of (III), Ba, Ca and Te are located on the A, B′ and B′′ sites, respectively. The Wyckoff positions and site symmetries of the four sites present in the structure of (III) are: Ba on 8c (3m), Ca on 4a (m m), Te on 4b (m m), and O on 24e (4m.m). Since Ba2CaTeO6 represents the highest possible symmetry of a double perovskite structure (cubic elpasolite-type in space group type Fm m), tilting of the B′O6 or B′′O6 octa­hedra (Howard et al., 2003 ▸), like in the monoclinic structure of Sr2CaTeO6 (Prior et al., 2005 ▸), is not observed. The ordering of the CaO6 and TeO6 octa­hedra in a checkerboard arrangement in (III) is displayed in Fig. 2 ▸.

Figure 2

Projection of the crystal structure of Ba2CaTeO6 (III) along [00]. [CaO6] octa­hedra are turquoise, [TeO6] octa­hedra are red, Ba sites blue and O sites pale grey. Displacement ellipsoids are drawn at the 97% probability level.

With the exception of the Na—O bond length, all other bond lengths (Table 1 ▸) are characteristic for their respective coordination polyhedra and in good agreement with mean values compiled recently for alkali and alkaline earth cations bonded to oxygen: K—O = 2.955 Å for coordination number (CN) 9, 3.095 Å for CN 12; Ca—O = 2.668 Å for CN 12; Ba—O = 2.689 Å for CN 6, 2.965 Å for CN 12 (Gagné & Hawthorne, 2016 ▸). The same is valid for the mean value of octa­hedrally coordinated TeVI with a mean Te—O bond length of 1.923 Å (Gagné & Hawthorne, 2018 ▸). As noted above, the Na—O bond length deviates from the mean value. At 2.3037 (16) Å it is considerably shorter than the mean of 2.441 Å for CN 6 (Gagné & Hawthorne, 2016 ▸). Such a compression has also been reported for other 6H-BaTiO3-type structures containing sodium. For example, the Na—O distance in K3NaOs2O9 has nearly the same value [2.313 (6) Å; Mogare et al., 2012 ▸] but is reported to be significantly shorter in Ba3NaRuIrO9 [2.058 (9) Å; Lufaso & zur Loye, 2005b ▸].

Synthesis and crystallization

Ba[H4TeO6] was prepared according to a literature protocol (Engelbrecht & Sladky, 1965 ▸) and its purity checked by X-ray powder diffraction. One gram of dried Ba[H4TeO6] was mixed with five grams of a KNO3/KI mixture (stoichiometric ratio 2:1) for (I) or a KNO3/NaNO3 mixture (stoichiometric ratio 1:1) for (II). The mixtures were placed in platinum crucibles and heated within six h to 773 K, held at that temperature for four days and cooled to room temperature within 12 h. The solidified melts were leached out with water and the remaining solid filtered off, washed with water and ethanol. Colourless single crystals with a hexa­gonal form for both (I) and (II) were selected from the reaction products. In one case a porcelain crucible was used to reproduce the formation of (I). In this batch, very few colourless crystals of Ba2CaTeO6 (III) had formed as a minor by-product. The porcelain crucible is an adventitious source of calcium that is present in feldspars such as oligoclase used for manufacturing.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2 ▸. For refinements of (I) and (II) the coordinates of isotypic Ba3LaRuO9 (Doi et al., 2002 ▸) were used as starting parameters. In the structure of (II), the M1 position with site symmetry 3m. of Wyckoff site 4f is stat­istically occupied by K+ and Ba2+ cations. For refinement of (III), the starting parameters were taken from the previous sructure determination based on X-ray powder diffraction data (Fu et al., 2008 ▸). The type of element on the metal positions was checked by free refinement of the respective site-occupation factors, which confirmed Ca and Ba, respectively.

Table 2

Experimental details

	(I)	(II)	(III)
Crystal data
Chemical formula	Ba2K2Te2O9	Ba2KNaTe2O9	Ba2CaTeO6
M r	752.08	735.97	538.36
Crystal system, space group	Hexagonal, P63/m m c	Hexagonal, P63/m m c	Cubic, F m m
Temperature (K)	298	293	293
a, b, c (Å)	6.047 (3), 6.047 (3), 16.479 (9)	5.9625 (3), 5.9625 (3), 14.9396 (8)	8.3536 (14), 8.3536 (14), 8.3536 (14)
α, β, γ (°)	90, 90, 120	90, 90, 120	90, 90, 90
V (Å3)	521.8 (6)	459.97 (5)	582.9 (3)
Z	2	2	4
Radiation type	Mo Kα	Mo Kα	Mo Kα
μ (mm−1)	13.80	15.25	19.18
Crystal size (mm)	0.09 × 0.09 × 0.01	0.10 × 0.10 × 0.01	0.08 × 0.08 × 0.08
Data collection
Diffractometer	Bruker APEXII CCD	Bruker APEXII CCD	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2015)	Multi-scan (SADABS; Bruker, 2015)	Multi-scan (SADABS; Bruker, 2015)
T min, T max	0.488, 0.748	0.540, 0.749	0.514, 0.748
No. of measured, independent and observed [I > 2σ(I)] reflections	21821, 754, 676	11701, 702, 669	11194, 131, 131
R int	0.041	0.029	0.139
(sin θ/λ)max (Å−1)	0.943	0.961	0.919
Refinement
R[F 2 > 2σ(F 2)], wR(F 2), S	0.015, 0.036, 1.15	0.018, 0.034, 1.49	0.019, 0.049, 1.33
No. of reflections	754	702	131
No. of parameters	22	23	7
Δρmax, Δρmin (e Å−3)	2.90, −2.02	1.02, −1.63	3.87, −1.68

Computer programs: APEX2 and SAINT (Bruker, 2015 ▸), SHELXL2017 (Sheldrick, 2015 ▸), ATOMS for Windows (Dowty, 2006 ▸) and publCIF (Westrip, 2010 ▸).

Crystal structure: contains datablock(s) I, II, III, global. DOI: 10.1107/S2056989018009064/pj2054sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S2056989018009064/pj2054Isup2.hkl

Structure factors: contains datablock(s) II. DOI: 10.1107/S2056989018009064/pj2054IIsup3.hkl

Structure factors: contains datablock(s) III. DOI: 10.1107/S2056989018009064/pj2054IIIsup4.hkl

CCDC references: 1850819, 1850818, 1850817

Additional supporting information: crystallographic information; 3D view; checkCIF report

Ba2K2Te2O9	Dx = 4.786 Mg m−3
Mr = 752.08	Mo Kα radiation, λ = 0.71073 Å
Hexagonal, P63/mmc	Cell parameters from 9371 reflections
a = 6.047 (3) Å	θ = 3.9–42.1°
c = 16.479 (9) Å	µ = 13.80 mm−1
V = 521.8 (6) Å3	T = 298 K
Z = 2	Plate, colourless
F(000) = 652	0.09 × 0.09 × 0.01 mm

Bruker APEXII CCD diffractometer	676 reflections with I > 2σ(I)
ω– and φ–scans	Rint = 0.041
Absorption correction: multi-scan (SADABS; Bruker, 2015)	θmax = 42.1°, θmin = 3.9°
Tmin = 0.488, Tmax = 0.748	h = −11→11
21821 measured reflections	k = −11→11
754 independent reflections	l = −31→30

Refinement on F2	0 restraints
Least-squares matrix: full	w = 1/[σ2(Fo2) + (0.0151P)2 + 0.8791P] where P = (Fo2 + 2Fc2)/3
R[F2 > 2σ(F2)] = 0.015	(Δ/σ)max < 0.001
wR(F2) = 0.036	Δρmax = 2.90 e Å−3
S = 1.15	Δρmin = −2.02 e Å−3
754 reflections	Extinction correction: SHELXL2014 (Sheldrick, 2015), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
22 parameters	Extinction coefficient: 0.0138 (4)

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

	x	y	z	Uiso*/Ueq
K1	0.3333	0.6667	0.87422 (7)	0.02257 (17)
Ba1	0.0000	0.0000	0.2500	0.00960 (5)
Te1	0.3333	0.6667	0.16206 (2)	0.00664 (4)
Ba2	0.0000	0.0000	0.0000	0.00851 (5)
O1	0.47142 (19)	0.9428 (4)	0.2500	0.0117 (3)
O2	0.17636 (16)	0.3527 (3)	0.38974 (10)	0.0198 (3)

	U11	U22	U33	U12	U13	U23
K1	0.0158 (2)	0.0158 (2)	0.0360 (5)	0.00792 (10)	0.000	0.000
Ba1	0.00959 (6)	0.00959 (6)	0.00961 (9)	0.00480 (3)	0.000	0.000
Te1	0.00661 (5)	0.00661 (5)	0.00671 (7)	0.00330 (3)	0.000	0.000
Ba2	0.00995 (6)	0.00995 (6)	0.00562 (8)	0.00498 (3)	0.000	0.000
O1	0.0150 (6)	0.0068 (7)	0.0106 (7)	0.0034 (3)	0.000	0.000
O2	0.0264 (6)	0.0116 (6)	0.0165 (6)	0.0058 (3)	0.0037 (3)	0.0075 (5)

K1—O1i	2.893 (2)	Ba1—O1xvii	3.0382 (17)
K1—O1ii	2.893 (2)	Ba1—O1xviii	3.0382 (17)
K1—O1iii	2.893 (2)	Ba1—O1xix	3.0382 (17)
K1—O2iv	3.0359 (17)	Ba1—O1xx	3.0382 (17)
K1—O2v	3.0359 (17)	Te1—O2xiii	1.8524 (18)
K1—O2vi	3.0359 (17)	Te1—O2xxi	1.8524 (18)
K1—O2vii	3.0359 (17)	Te1—O2xxii	1.8525 (18)
K1—O2viii	3.0360 (17)	Te1—O1	2.0474 (16)
K1—O2ix	3.0360 (17)	Te1—O1xvii	2.0474 (16)
Ba1—O2x	2.952 (2)	Te1—O1xv	2.0474 (16)
Ba1—O2xi	2.952 (2)	Ba2—O2x	2.5910 (18)
Ba1—O2	2.952 (2)	Ba2—O2xxiii	2.5910 (18)
Ba1—O2xii	2.952 (2)	Ba2—O2xiii	2.5911 (18)
Ba1—O2xiii	2.952 (2)	Ba2—O2xxiv	2.5911 (18)
Ba1—O2xiv	2.952 (2)	Ba2—O2xii	2.5911 (18)
Ba1—O1xv	3.0382 (17)	Ba2—O2xxv	2.5911 (18)
Ba1—O1xvi	3.0382 (17)
O1i—K1—O1ii	75.48 (6)	O1xvi—Ba1—O1xviii	48.69 (7)
O1i—K1—O1iii	75.48 (6)	O1xvii—Ba1—O1xviii	71.31 (7)
O1ii—K1—O1iii	75.48 (6)	O2x—Ba1—O1xix	55.25 (3)
O1i—K1—O2iv	94.78 (4)	O2xi—Ba1—O1xix	55.25 (3)
O1ii—K1—O2iv	55.82 (4)	O2—Ba1—O1xix	120.56 (3)
O1iii—K1—O2iv	131.10 (5)	O2xii—Ba1—O1xix	93.53 (2)
O1i—K1—O2v	55.82 (4)	O2xiii—Ba1—O1xix	120.56 (3)
O1ii—K1—O2v	94.78 (4)	O2xiv—Ba1—O1xix	93.53 (2)
O1iii—K1—O2v	131.10 (5)	O1xv—Ba1—O1xix	120.0
O2iv—K1—O2v	63.59 (6)	O1xvi—Ba1—O1xix	71.31 (8)
O1i—K1—O2vi	131.10 (5)	O1xvii—Ba1—O1xix	168.69 (8)
O1ii—K1—O2vi	55.82 (4)	O1xviii—Ba1—O1xix	120.0
O1iii—K1—O2vi	94.77 (4)	O2x—Ba1—O1xx	55.25 (4)
O2iv—K1—O2vi	55.94 (7)	O2xi—Ba1—O1xx	55.25 (3)
O2v—K1—O2vi	119.299 (12)	O2—Ba1—O1xx	93.53 (2)
O1i—K1—O2vii	55.82 (4)	O2xii—Ba1—O1xx	120.56 (3)
O1ii—K1—O2vii	131.10 (5)	O2xiii—Ba1—O1xx	93.53 (2)
O1iii—K1—O2vii	94.78 (4)	O2xiv—Ba1—O1xx	120.56 (3)
O2iv—K1—O2vii	119.299 (12)	O1xv—Ba1—O1xx	71.31 (8)
O2v—K1—O2vii	55.94 (7)	O1xvi—Ba1—O1xx	120.0
O2vi—K1—O2vii	169.60 (8)	O1xvii—Ba1—O1xx	120.0
O1i—K1—O2viii	131.10 (5)	O1xviii—Ba1—O1xx	168.69 (8)
O1ii—K1—O2viii	94.78 (4)	O1xix—Ba1—O1xx	48.69 (8)
O1iii—K1—O2viii	55.82 (4)	O2xiii—Te1—O2xxi	100.46 (7)
O2iv—K1—O2viii	119.298 (12)	O2xiii—Te1—O2xxii	100.45 (7)
O2v—K1—O2viii	169.60 (8)	O2xxi—Te1—O2xxii	100.45 (7)
O2vi—K1—O2viii	63.59 (6)	O2xiii—Te1—O1	162.38 (7)
O2vii—K1—O2viii	119.297 (12)	O2xxi—Te1—O1	90.73 (6)
O1i—K1—O2ix	94.78 (4)	O2xxii—Te1—O1	90.73 (6)
O1ii—K1—O2ix	131.10 (5)	O2xiii—Te1—O1xvii	90.73 (6)
O1iii—K1—O2ix	55.82 (4)	O2xxi—Te1—O1xvii	162.38 (7)
O2iv—K1—O2ix	169.60 (8)	O2xxii—Te1—O1xvii	90.73 (6)
O2v—K1—O2ix	119.298 (12)	O1—Te1—O1xvii	75.43 (7)
O2vi—K1—O2ix	119.297 (12)	O2xiii—Te1—O1xv	90.73 (6)
O2vii—K1—O2ix	63.59 (6)	O2xxi—Te1—O1xv	90.73 (6)
O2viii—K1—O2ix	55.93 (7)	O2xxii—Te1—O1xv	162.38 (7)
O2x—Ba1—O2xi	102.53 (7)	O1—Te1—O1xv	75.43 (7)
O2x—Ba1—O2	143.54 (3)	O1xvii—Te1—O1xv	75.43 (7)
O2xi—Ba1—O2	65.62 (6)	O2x—Ba2—O2xxiii	180.00 (5)
O2x—Ba1—O2xii	65.62 (6)	O2x—Ba2—O2xiii	76.25 (7)
O2xi—Ba1—O2xii	143.54 (3)	O2xxiii—Ba2—O2xiii	103.75 (7)
O2—Ba1—O2xii	143.54 (3)	O2x—Ba2—O2xxiv	103.75 (7)
O2x—Ba1—O2xiii	65.62 (6)	O2xxiii—Ba2—O2xxiv	76.25 (7)
O2xi—Ba1—O2xiii	143.54 (3)	O2xiii—Ba2—O2xxiv	180.00 (8)
O2—Ba1—O2xiii	102.53 (7)	O2x—Ba2—O2xii	76.25 (7)
O2xii—Ba1—O2xiii	65.62 (6)	O2xxiii—Ba2—O2xii	103.75 (7)
O2x—Ba1—O2xiv	143.54 (3)	O2xiii—Ba2—O2xii	76.25 (7)
O2xi—Ba1—O2xiv	65.62 (6)	O2xxiv—Ba2—O2xii	103.75 (7)
O2—Ba1—O2xiv	65.62 (6)	O2x—Ba2—O2xxv	103.75 (7)
O2xii—Ba1—O2xiv	102.53 (7)	O2xxiii—Ba2—O2xxv	76.25 (7)
O2xiii—Ba1—O2xiv	143.54 (3)	O2xiii—Ba2—O2xxv	103.75 (7)
O2x—Ba1—O1xv	93.53 (2)	O2xxiv—Ba2—O2xxv	76.25 (7)
O2xi—Ba1—O1xv	93.53 (2)	O2xii—Ba2—O2xxv	180.00 (5)
O2—Ba1—O1xv	55.25 (3)	Te1xiii—O1—Te1	90.11 (9)
O2xii—Ba1—O1xv	120.56 (3)	Te1xiii—O1—K1xxvi	89.91 (5)
O2xiii—Ba1—O1xv	55.25 (4)	Te1—O1—K1xxvi	179.97 (5)
O2xiv—Ba1—O1xv	120.56 (3)	Te1xiii—O1—K1ii	179.97 (12)
O2x—Ba1—O1xvi	93.53 (2)	Te1—O1—K1ii	89.91 (5)
O2xi—Ba1—O1xvi	93.53 (2)	K1xxvi—O1—K1ii	90.06 (8)
O2—Ba1—O1xvi	120.56 (3)	Te1xiii—O1—Ba1xxvii	93.99 (2)
O2xii—Ba1—O1xvi	55.25 (3)	Te1—O1—Ba1xxvii	93.99 (2)
O2xiii—Ba1—O1xvi	120.56 (3)	K1xxvi—O1—Ba1xxvii	86.01 (3)
O2xiv—Ba1—O1xvi	55.25 (3)	K1ii—O1—Ba1xxvii	86.01 (3)
O1xv—Ba1—O1xvi	168.69 (7)	Te1xiii—O1—Ba1xxviii	93.99 (2)
O2x—Ba1—O1xvii	120.56 (3)	Te1—O1—Ba1xxviii	93.99 (2)
O2xi—Ba1—O1xvii	120.56 (3)	K1xxvi—O1—Ba1xxviii	86.01 (3)
O2—Ba1—O1xvii	55.25 (3)	K1ii—O1—Ba1xxviii	86.01 (3)
O2xii—Ba1—O1xvii	93.53 (2)	Ba1xxvii—O1—Ba1xxviii	168.69 (7)
O2xiii—Ba1—O1xvii	55.24 (3)	Te1xiii—O2—Ba2xxix	162.91 (9)
O2xiv—Ba1—O1xvii	93.53 (2)	Te1xiii—O2—Ba1	101.29 (8)
O1xv—Ba1—O1xvii	48.69 (8)	Ba2xxix—O2—Ba1	95.79 (7)
O1xvi—Ba1—O1xvii	120.0	Te1xiii—O2—K1xxx	89.48 (3)
O2x—Ba1—O1xviii	120.56 (3)	Ba2xxix—O2—K1xxx	92.02 (3)
O2xi—Ba1—O1xviii	120.56 (3)	Ba1—O2—K1xxx	85.03 (4)
O2—Ba1—O1xviii	93.53 (2)	Te1xiii—O2—K1xxxi	89.48 (3)
O2xii—Ba1—O1xviii	55.24 (3)	Ba2xxix—O2—K1xxxi	92.02 (3)
O2xiii—Ba1—O1xviii	93.53 (2)	Ba1—O2—K1xxxi	85.03 (4)
O2xiv—Ba1—O1xviii	55.24 (3)	K1xxx—O2—K1xxxi	169.60 (8)
O1xv—Ba1—O1xviii	120.0

Ba2KNaTe2O9	Dx = 5.314 Mg m−3
Mr = 735.97	Mo Kα radiation, λ = 0.71073 Å
Hexagonal, P63/mmc	Cell parameters from 9985 reflections
a = 5.9625 (3) Å	θ = 2.7–42.9°
c = 14.9396 (8) Å	µ = 15.25 mm−1
V = 459.97 (5) Å3	T = 293 K
Z = 2	Plate, colourless
F(000) = 636	0.10 × 0.10 × 0.01 mm

Bruker APEXII CCD diffractometer	669 reflections with I > 2σ(I)
ω– and φ–scans	Rint = 0.029
Absorption correction: multi-scan (SADABS; Bruker, 2015)	θmax = 43.1°, θmin = 2.7°
Tmin = 0.540, Tmax = 0.749	h = −11→11
11701 measured reflections	k = −11→8
702 independent reflections	l = −28→28

Refinement on F2	0 restraints
Least-squares matrix: full	w = 1/[σ2(Fo2) + (0.0075P)2 + 0.5711P] where P = (Fo2 + 2Fc2)/3
R[F2 > 2σ(F2)] = 0.018	(Δ/σ)max = 0.001
wR(F2) = 0.034	Δρmax = 1.02 e Å−3
S = 1.49	Δρmin = −1.63 e Å−3
702 reflections	Extinction correction: SHELXL2014 (Sheldrick, 2015), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
23 parameters	Extinction coefficient: 0.0409 (10)

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

	x	y	z	Uiso*/Ueq	Occ. (<1)
BaK1	0.3333	0.6667	0.91703 (2)	0.01251 (6)	0.5
KBA1	0.3333	0.6667	0.91703 (2)	0.01251 (6)	0.5
Ba1	0.0000	0.0000	0.2500	0.00953 (5)
Te1	0.3333	0.6667	0.15383 (2)	0.00583 (5)
Na2	0.0000	0.0000	0.0000	0.0110 (3)
O1	0.47381 (18)	0.9476 (4)	0.2500	0.0101 (3)
O2	0.17638 (16)	0.3528 (3)	0.40559 (12)	0.0195 (3)

	U11	U22	U33	U12	U13	U23
BaK1	0.01060 (8)	0.01060 (8)	0.01631 (11)	0.00530 (4)	0.000	0.000
KBA1	0.01060 (8)	0.01060 (8)	0.01631 (11)	0.00530 (4)	0.000	0.000
Ba1	0.00874 (7)	0.00874 (7)	0.01112 (9)	0.00437 (3)	0.000	0.000
Te1	0.00573 (5)	0.00573 (5)	0.00603 (7)	0.00287 (3)	0.000	0.000
Na2	0.0118 (5)	0.0118 (5)	0.0094 (7)	0.0059 (2)	0.000	0.000
O1	0.0107 (5)	0.0060 (6)	0.0121 (6)	0.0030 (3)	0.000	0.000
O2	0.0235 (6)	0.0120 (6)	0.0192 (6)	0.0060 (3)	0.0045 (3)	0.0089 (5)

BaK1—O2i	2.9878 (2)	Ba1—O1xviii	2.9935 (14)
BaK1—O2ii	2.9878 (2)	Ba1—O1xix	2.9935 (14)
BaK1—O2iii	2.9878 (2)	Ba1—O1xx	2.9935 (14)
BaK1—O2iv	2.9878 (2)	Ba1—O1xxi	2.9935 (14)
BaK1—O2v	2.9878 (2)	Ba1—O1xxii	2.9935 (14)
BaK1—O2vi	2.9879 (2)	Ba1—O1xxiii	2.9935 (14)
BaK1—O2vii	3.1064 (18)	Te1—O2xxiv	1.8481 (16)
BaK1—O2viii	3.1064 (19)	Te1—O2xiv	1.8481 (16)
BaK1—O2ix	3.1064 (19)	Te1—O2xxv	1.8481 (16)
BaK1—O1x	3.1927 (12)	Te1—O1xx	2.0418 (14)
BaK1—O1xi	3.1927 (12)	Te1—O1xviii	2.0418 (14)
BaK1—O1xii	3.1927 (12)	Te1—O1	2.0418 (14)
Ba1—O2xiii	2.9532 (18)	Na2—O2xiv	2.3037 (16)
Ba1—O2xiv	2.9532 (18)	Na2—O2xxvi	2.3037 (16)
Ba1—O2xv	2.9532 (18)	Na2—O2xiii	2.3037 (16)
Ba1—O2	2.9532 (18)	Na2—O2xxvii	2.3037 (16)
Ba1—O2xvi	2.9532 (18)	Na2—O2xvi	2.3038 (16)
Ba1—O2xvii	2.9532 (18)	Na2—O2xxviii	2.3038 (16)
O2i—BaK1—O2ii	56.05 (6)	O2xv—Ba1—O1xxii	93.19 (2)
O2i—BaK1—O2iii	63.74 (7)	O2—Ba1—O1xxii	120.27 (3)
O2ii—BaK1—O2iii	119.677 (7)	O2xvi—Ba1—O1xxii	55.95 (3)
O2i—BaK1—O2iv	119.677 (7)	O2xvii—Ba1—O1xxii	55.95 (3)
O2ii—BaK1—O2iv	63.74 (7)	O1xviii—Ba1—O1xxii	120.0
O2iii—BaK1—O2iv	172.40 (6)	O1xix—Ba1—O1xxii	70.37 (7)
O2i—BaK1—O2v	119.676 (7)	O1xx—Ba1—O1xxii	169.63 (7)
O2ii—BaK1—O2v	172.40 (6)	O1xxi—Ba1—O1xxii	120.0
O2iii—BaK1—O2v	56.04 (6)	O2xiii—Ba1—O1xxiii	120.27 (3)
O2iv—BaK1—O2v	119.675 (7)	O2xiv—Ba1—O1xxiii	93.19 (2)
O2i—BaK1—O2vi	172.40 (6)	O2xv—Ba1—O1xxiii	120.27 (3)
O2ii—BaK1—O2vi	119.676 (7)	O2—Ba1—O1xxiii	93.20 (2)
O2iii—BaK1—O2vi	119.675 (7)	O2xvi—Ba1—O1xxiii	55.95 (3)
O2iv—BaK1—O2vi	56.04 (6)	O2xvii—Ba1—O1xxiii	55.95 (3)
O2v—BaK1—O2vi	63.74 (6)	O1xviii—Ba1—O1xxiii	70.37 (7)
O2i—BaK1—O2vii	120.56 (3)	O1xix—Ba1—O1xxiii	120.0
O2ii—BaK1—O2vii	120.56 (3)	O1xx—Ba1—O1xxiii	120.0
O2iii—BaK1—O2vii	91.79 (4)	O1xxi—Ba1—O1xxiii	169.63 (7)
O2iv—BaK1—O2vii	91.79 (4)	O1xxii—Ba1—O1xxiii	49.63 (7)
O2v—BaK1—O2vii	66.84 (5)	O2xxiv—Te1—O2xiv	98.85 (7)
O2vi—BaK1—O2vii	66.84 (5)	O2xxiv—Te1—O2xxv	98.85 (7)
O2i—BaK1—O2viii	91.79 (4)	O2xiv—Te1—O2xxv	98.85 (7)
O2ii—BaK1—O2viii	66.84 (5)	O2xxiv—Te1—O1xx	91.52 (5)
O2iii—BaK1—O2viii	120.56 (3)	O2xiv—Te1—O1xx	91.51 (5)
O2iv—BaK1—O2viii	66.84 (5)	O2xxv—Te1—O1xx	163.99 (7)
O2v—BaK1—O2viii	120.56 (3)	O2xxiv—Te1—O1xviii	163.99 (7)
O2vi—BaK1—O2viii	91.79 (4)	O2xiv—Te1—O1xviii	91.51 (5)
O2vii—BaK1—O2viii	53.73 (5)	O2xxv—Te1—O1xviii	91.51 (5)
O2i—BaK1—O2ix	66.84 (5)	O1xx—Te1—O1xviii	75.95 (6)
O2ii—BaK1—O2ix	91.79 (4)	O2xxiv—Te1—O1	91.51 (5)
O2iii—BaK1—O2ix	66.84 (5)	O2xiv—Te1—O1	163.99 (7)
O2iv—BaK1—O2ix	120.56 (3)	O2xxv—Te1—O1	91.52 (5)
O2v—BaK1—O2ix	91.79 (4)	O1xx—Te1—O1	75.95 (6)
O2vi—BaK1—O2ix	120.56 (3)	O1xviii—Te1—O1	75.95 (6)
O2vii—BaK1—O2ix	53.73 (5)	O2xiv—Na2—O2xxvi	180.00 (9)
O2viii—BaK1—O2ix	53.73 (5)	O2xiv—Na2—O2xiii	86.43 (7)
O2i—BaK1—O1x	88.64 (4)	O2xxvi—Na2—O2xiii	93.57 (7)
O2ii—BaK1—O1x	118.94 (4)	O2xiv—Na2—O2xxvii	93.57 (7)
O2iii—BaK1—O1x	53.54 (4)	O2xxvi—Na2—O2xxvii	86.43 (7)
O2iv—BaK1—O1x	118.94 (4)	O2xiii—Na2—O2xxvii	180.00 (9)
O2v—BaK1—O1x	53.54 (4)	O2xiv—Na2—O2xvi	86.43 (7)
O2vi—BaK1—O1x	88.64 (4)	O2xxvi—Na2—O2xvi	93.57 (7)
O2vii—BaK1—O1x	120.26 (3)	O2xiii—Na2—O2xvi	86.43 (7)
O2viii—BaK1—O1x	172.86 (4)	O2xxvii—Na2—O2xvi	93.57 (7)
O2ix—BaK1—O1x	120.26 (3)	O2xiv—Na2—O2xxviii	93.57 (7)
O2i—BaK1—O1xi	118.94 (4)	O2xxvi—Na2—O2xxviii	86.43 (7)
O2ii—BaK1—O1xi	88.64 (4)	O2xiii—Na2—O2xxviii	93.57 (7)
O2iii—BaK1—O1xi	118.94 (4)	O2xxvii—Na2—O2xxviii	86.43 (7)
O2iv—BaK1—O1xi	53.54 (4)	O2xvi—Na2—O2xxviii	180.00 (7)
O2v—BaK1—O1xi	88.64 (4)	Te1xiv—O1—Te1	89.44 (8)
O2vi—BaK1—O1xi	53.54 (4)	Te1xiv—O1—Ba1xxix	93.68 (2)
O2vii—BaK1—O1xi	120.26 (3)	Te1—O1—Ba1xxix	93.68 (2)
O2viii—BaK1—O1xi	120.26 (3)	Te1xiv—O1—Ba1xxx	93.68 (2)
O2ix—BaK1—O1xi	172.86 (4)	Te1—O1—Ba1xxx	93.68 (2)
O1x—BaK1—O1xi	65.40 (4)	Ba1xxix—O1—Ba1xxx	169.63 (7)
O2i—BaK1—O1xii	53.54 (4)	Te1xiv—O1—BaK1xxxi	83.874 (13)
O2ii—BaK1—O1xii	53.54 (4)	Te1—O1—BaK1xxxi	173.32 (6)
O2iii—BaK1—O1xii	88.64 (4)	Ba1xxix—O1—BaK1xxxi	86.77 (2)
O2iv—BaK1—O1xii	88.64 (4)	Ba1xxx—O1—BaK1xxxi	86.77 (2)
O2v—BaK1—O1xii	118.94 (4)	Te1xiv—O1—KBA1xxxi	83.874 (13)
O2vi—BaK1—O1xii	118.94 (4)	Te1—O1—KBA1xxxi	173.32 (6)
O2vii—BaK1—O1xii	172.86 (4)	Ba1xxix—O1—KBA1xxxi	86.77 (2)
O2viii—BaK1—O1xii	120.26 (3)	Ba1xxx—O1—KBA1xxxi	86.77 (2)
O2ix—BaK1—O1xii	120.26 (3)	BaK1xxxi—O1—KBA1xxxi	0.000 (7)
O1x—BaK1—O1xii	65.40 (4)	Te1xiv—O1—BaK1xi	173.32 (6)
O1xi—BaK1—O1xii	65.40 (4)	Te1—O1—BaK1xi	83.874 (13)
O2xiii—Ba1—O2xiv	64.58 (5)	Ba1xxix—O1—BaK1xi	86.77 (2)
O2xiii—Ba1—O2xv	103.83 (6)	Ba1xxx—O1—BaK1xi	86.77 (2)
O2xiv—Ba1—O2xv	144.07 (2)	BaK1xxxi—O1—BaK1xi	102.81 (5)
O2xiii—Ba1—O2	144.07 (3)	KBA1xxxi—O1—BaK1xi	102.8
O2xiv—Ba1—O2	103.83 (6)	Te1xiv—O1—KBA1xi	173.32 (6)
O2xv—Ba1—O2	64.58 (5)	Te1—O1—KBA1xi	83.874 (13)
O2xiii—Ba1—O2xvi	64.58 (5)	Ba1xxix—O1—KBA1xi	86.77 (2)
O2xiv—Ba1—O2xvi	64.58 (5)	Ba1xxx—O1—KBA1xi	86.77 (2)
O2xv—Ba1—O2xvi	144.07 (2)	BaK1xxxi—O1—KBA1xi	102.81 (5)
O2—Ba1—O2xvi	144.07 (2)	KBA1xxxi—O1—KBA1xi	102.81 (5)
O2xiii—Ba1—O2xvii	144.07 (3)	BaK1xi—O1—KBA1xi	0.000 (7)
O2xiv—Ba1—O2xvii	144.07 (3)	Te1xiv—O2—Na2xxxii	170.96 (10)
O2xv—Ba1—O2xvii	64.58 (5)	Te1xiv—O2—Ba1	99.37 (7)
O2—Ba1—O2xvii	64.58 (5)	Na2xxxii—O2—Ba1	89.67 (6)
O2xvi—Ba1—O2xvii	103.83 (6)	Te1xiv—O2—BaK1xxxiii	93.26 (3)
O2xiii—Ba1—O1xviii	120.27 (3)	Na2xxxii—O2—BaK1xxxiii	86.47 (3)
O2xiv—Ba1—O1xviii	55.95 (3)	Ba1—O2—BaK1xxxiii	91.39 (4)
O2xv—Ba1—O1xviii	120.27 (3)	Te1xiv—O2—KBA1xxxiii	93.26 (3)
O2—Ba1—O1xviii	55.95 (3)	Na2xxxii—O2—KBA1xxxiii	86.47 (3)
O2xvi—Ba1—O1xviii	93.20 (2)	Ba1—O2—KBA1xxxiii	91.39 (4)
O2xvii—Ba1—O1xviii	93.19 (2)	BaK1xxxiii—O2—KBA1xxxiii	0.000 (13)
O2xiii—Ba1—O1xix	55.95 (3)	Te1xiv—O2—BaK1xxxiv	93.26 (3)
O2xiv—Ba1—O1xix	120.27 (3)	Na2xxxii—O2—BaK1xxxiv	86.47 (3)
O2xv—Ba1—O1xix	55.95 (3)	Ba1—O2—BaK1xxxiv	91.39 (4)
O2—Ba1—O1xix	120.27 (3)	BaK1xxxiii—O2—BaK1xxxiv	172.40 (6)
O2xvi—Ba1—O1xix	93.20 (2)	KBA1xxxiii—O2—BaK1xxxiv	172.4
O2xvii—Ba1—O1xix	93.20 (2)	Te1xiv—O2—KBA1xxxiv	93.26 (3)
O1xviii—Ba1—O1xix	169.63 (7)	Na2xxxii—O2—KBA1xxxiv	86.47 (3)
O2xiii—Ba1—O1xx	93.20 (2)	Ba1—O2—KBA1xxxiv	91.39 (4)
O2xiv—Ba1—O1xx	55.95 (3)	BaK1xxxiii—O2—KBA1xxxiv	172.40 (6)
O2xv—Ba1—O1xx	93.20 (2)	KBA1xxxiii—O2—KBA1xxxiv	172.40 (6)
O2—Ba1—O1xx	55.95 (3)	BaK1xxxiv—O2—KBA1xxxiv	0.0
O2xvi—Ba1—O1xx	120.27 (3)	Te1xiv—O2—KBA1ix	87.26 (6)
O2xvii—Ba1—O1xx	120.27 (3)	Na2xxxii—O2—KBA1ix	83.70 (5)
O1xviii—Ba1—O1xx	49.63 (7)	Ba1—O2—KBA1ix	173.37 (6)
O1xix—Ba1—O1xx	120.0	BaK1xxxiii—O2—KBA1ix	88.21 (4)
O2xiii—Ba1—O1xxi	55.95 (3)	KBA1xxxiii—O2—KBA1ix	88.21 (4)
O2xiv—Ba1—O1xxi	93.20 (2)	BaK1xxxiv—O2—KBA1ix	88.21 (4)
O2xv—Ba1—O1xxi	55.95 (3)	KBA1xxxiv—O2—KBA1ix	88.21 (4)
O2—Ba1—O1xxi	93.20 (2)	Te1xiv—O2—BaK1ix	87.26 (6)
O2xvi—Ba1—O1xxi	120.27 (3)	Na2xxxii—O2—BaK1ix	83.70 (5)
O2xvii—Ba1—O1xxi	120.27 (3)	Ba1—O2—BaK1ix	173.37 (6)
O1xviii—Ba1—O1xxi	120.0	BaK1xxxiii—O2—BaK1ix	88.21 (4)
O1xix—Ba1—O1xxi	49.63 (7)	KBA1xxxiii—O2—BaK1ix	88.2
O1xx—Ba1—O1xxi	70.37 (7)	BaK1xxxiv—O2—BaK1ix	88.21 (4)
O2xiii—Ba1—O1xxii	93.19 (2)	KBA1xxxiv—O2—BaK1ix	88.2
O2xiv—Ba1—O1xxii	120.27 (3)	KBA1ix—O2—BaK1ix	0.0

Ba2CaTeO6	Mo Kα radiation, λ = 0.71073 Å
Mr = 538.36	Cell parameters from 5256 reflections
Cubic, Fm3m	θ = 4.2–40.4°
a = 8.3536 (14) Å	µ = 19.18 mm−1
V = 582.9 (3) Å3	T = 293 K
Z = 4	Octahedron, colourless
F(000) = 928	0.08 × 0.08 × 0.08 mm
Dx = 6.134 Mg m−3

Bruker APEXII CCD diffractometer	131 reflections with I > 2σ(I)
φ– and ω–scans	Rint = 0.139
Absorption correction: multi-scan (SADABS; Bruker, 2015)	θmax = 40.8°, θmin = 4.2°
Tmin = 0.514, Tmax = 0.748	h = −15→15
11194 measured reflections	k = −15→15
131 independent reflections	l = −15→15

Refinement on F2	7 parameters
Least-squares matrix: full	0 restraints
R[F2 > 2σ(F2)] = 0.019	w = 1/[σ2(Fo2) + (0.0237P)2 + 1.8403P] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.049	(Δ/σ)max < 0.001
S = 1.33	Δρmax = 3.87 e Å−3
131 reflections	Δρmin = −1.68 e Å−3

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

	x	y	z	Uiso*/Ueq
Ba	0.250000	0.250000	0.250000	0.00957 (13)
Ca	0.000000	0.000000	0.000000	0.0066 (2)
Te	0.500000	0.500000	0.500000	0.00602 (13)
O	0.2690 (4)	0.000000	0.000000	0.0203 (6)

	U11	U22	U33	U12	U13	U23
Ba	0.00957 (13)	0.00957 (13)	0.00957 (13)	0.000	0.000	0.000
Ca	0.0066 (2)	0.0066 (2)	0.0066 (2)	0.000	0.000	0.000
Te	0.00602 (13)	0.00602 (13)	0.00602 (13)	0.000	0.000	0.000
O	0.0201 (12)	0.0203 (8)	0.0203 (8)	0.000	0.000	0.000

Ba—Oi	2.9577 (5)	Ca—O	2.247 (3)
Ba—Oii	2.9577 (5)	Ca—Oxii	2.247 (3)
Ba—O	2.9577 (5)	Ca—Oiv	2.247 (3)
Ba—Oiii	2.9577 (5)	Ca—Oxiii	2.247 (3)
Ba—Oiv	2.9577 (5)	Ca—Ov	2.247 (3)
Ba—Ov	2.9577 (5)	Ca—Oxiv	2.247 (3)
Ba—Ovi	2.9577 (5)	Te—Oxv	1.930 (3)
Ba—Ovii	2.9577 (5)	Te—Oiii	1.930 (3)
Ba—Oviii	2.9577 (5)	Te—Oxvi	1.930 (3)
Ba—Oix	2.9577 (5)	Te—Oi	1.930 (3)
Ba—Ox	2.9577 (5)	Te—Oxvii	1.930 (3)
Ba—Oxi	2.9577 (5)	Te—Oii	1.930 (3)
Oi—Ba—Oii	54.95 (11)	Oii—Ba—Oxi	90.165 (7)
Oi—Ba—O	119.905 (4)	O—Ba—Oxi	90.165 (7)
Oii—Ba—O	173.85 (13)	Oiii—Ba—Oxi	119.905 (4)
Oi—Ba—Oiii	54.95 (11)	Oiv—Ba—Oxi	54.95 (11)
Oii—Ba—Oiii	54.95 (11)	Ov—Ba—Oxi	119.905 (4)
O—Ba—Oiii	119.905 (4)	Ovi—Ba—Oxi	64.99 (11)
Oi—Ba—Oiv	119.905 (4)	Ovii—Ba—Oxi	119.905 (4)
Oii—Ba—Oiv	119.905 (4)	Oviii—Ba—Oxi	119.905 (4)
O—Ba—Oiv	64.99 (11)	Oix—Ba—Oxi	54.95 (11)
Oiii—Ba—Oiv	173.85 (13)	Ox—Ba—Oxi	173.85 (13)
Oi—Ba—Ov	173.85 (13)	O—Ca—Oxii	90.0
Oii—Ba—Ov	119.905 (4)	O—Ca—Oiv	90.0
O—Ba—Ov	64.99 (11)	Oxii—Ca—Oiv	180.0
Oiii—Ba—Ov	119.905 (4)	O—Ca—Oxiii	90.0
Oiv—Ba—Ov	64.99 (11)	Oxii—Ca—Oxiii	90.0
Oi—Ba—Ovi	64.99 (11)	Oiv—Ca—Oxiii	90.0
Oii—Ba—Ovi	119.905 (4)	O—Ca—Ov	90.0
O—Ba—Ovi	54.95 (11)	Oxii—Ca—Ov	90.0
Oiii—Ba—Ovi	90.165 (7)	Oiv—Ca—Ov	90.0
Oiv—Ba—Ovi	90.165 (7)	Oxiii—Ca—Ov	180.0
Ov—Ba—Ovi	119.905 (4)	O—Ca—Oxiv	180.0
Oi—Ba—Ovii	119.905 (4)	Oxii—Ca—Oxiv	90.0
Oii—Ba—Ovii	64.99 (11)	Oiv—Ca—Oxiv	90.0
O—Ba—Ovii	119.905 (4)	Oxiii—Ca—Oxiv	90.0
Oiii—Ba—Ovii	90.165 (7)	Ov—Ca—Oxiv	90.0
Oiv—Ba—Ovii	90.165 (7)	Oxv—Te—Oiii	180.0
Ov—Ba—Ovii	54.95 (11)	Oxv—Te—Oxvi	90.0
Ovi—Ba—Ovii	173.85 (13)	Oiii—Te—Oxvi	90.0
Oi—Ba—Oviii	90.165 (7)	Oxv—Te—Oi	90.0
Oii—Ba—Oviii	119.905 (4)	Oiii—Te—Oi	90.0
O—Ba—Oviii	54.95 (11)	Oxvi—Te—Oi	180.0
Oiii—Ba—Oviii	64.99 (11)	Oxv—Te—Oxvii	90.000 (1)
Oiv—Ba—Oviii	119.905 (4)	Oiii—Te—Oxvii	90.0
Ov—Ba—Oviii	90.165 (7)	Oxvi—Te—Oxvii	90.000 (1)
Ovi—Ba—Oviii	54.95 (11)	Oi—Te—Oxvii	90.0
Ovii—Ba—Oviii	119.905 (4)	Oxv—Te—Oii	90.0
Oi—Ba—Oix	90.165 (7)	Oiii—Te—Oii	90.000 (1)
Oii—Ba—Oix	64.99 (11)	Oxvi—Te—Oii	90.0
O—Ba—Oix	119.905 (4)	Oi—Te—Oii	90.000 (1)
Oiii—Ba—Oix	119.905 (4)	Oxvii—Te—Oii	180.0
Oiv—Ba—Oix	54.95 (11)	Texviii—O—Ca	180.0
Ov—Ba—Oix	90.165 (7)	Texviii—O—Baxviii	93.08 (7)
Ovi—Ba—Oix	119.905 (4)	Ca—O—Baxviii	86.92 (7)
Ovii—Ba—Oix	64.99 (11)	Texviii—O—Ba	93.08 (7)
Oviii—Ba—Oix	173.85 (13)	Ca—O—Ba	86.92 (7)
Oi—Ba—Ox	119.905 (4)	Baxviii—O—Ba	173.85 (13)
Oii—Ba—Ox	90.165 (7)	Texviii—O—Bax	93.08 (7)
O—Ba—Ox	90.165 (7)	Ca—O—Bax	86.92 (7)
Oiii—Ba—Ox	64.99 (11)	Baxviii—O—Bax	89.835 (7)
Oiv—Ba—Ox	119.905 (4)	Ba—O—Bax	89.835 (7)
Ov—Ba—Ox	54.95 (11)	Texviii—O—Baxi	93.08 (7)
Ovi—Ba—Ox	119.905 (4)	Ca—O—Baxi	86.92 (7)
Ovii—Ba—Ox	54.95 (11)	Baxviii—O—Baxi	89.835 (7)
Oviii—Ba—Ox	64.99 (11)	Ba—O—Baxi	89.835 (7)
Oix—Ba—Ox	119.905 (4)	Bax—O—Baxi	173.85 (13)
Oi—Ba—Oxi	64.99 (11)