A new lanthanum titanium oxy­sulfide, La₁₆Ti₅S_17+xO₁₇, with x = 0.75 (9)

The title compound, hexadecalanthanum pentatitanium heptadeca­sulfide heptadecaoxide, La₁₆Ti₅S_17+xO₁₇ [x = 0.75 (9)], has been obtained as a by-product in the preparation of new oxy­chalcogenide compounds in the La/Ti/Ag/S/O system. La₁₆Ti₅S_17+xO₁₇ crystallizes in the tetragonal system (space group I4/m) and is isostructural with Nd₁₆Ti₅S₁₇O₁₇. The structure of the title compound consists of an [La₂S₂] rock-salt-type framework, which delimits [001] square channels containing two types of chains of corner-sharing Ti(O,S)₆ octahedra. These chains are connected through La(O,S)_n polyhedra.

S1. Comment

Recent explorations in the chemistry of oxychalcogenides, and particularly in quaternary systems of the type M/T/X/O (M is a rare earth metal, T is a transition metal, and X = S and Se), show that M and T atoms always bond preferentially to a particular anion (O or X), thus leading to segregated oxide or chalcogenide building blocks within the structure. For instance, the Ln₂Ti₂S₂O₅ compounds (Ln = Pr–Er) exhibit a structure type where such a segregation occurs (Boyer et al., 1999; Goga et al., 1999). In these compounds, a sulfide slab of composition [Ln₂S₂] is separated by an oxide slab built from the corner-sharing O atoms of two adjacent layers of Ti octahedra?.

The present structural study of La₁₆Ti₅S_{17 + x}O₁₇ shows that the structure can be described on the basis of an [La₂S₂] framework that delimits channels of squared sections. These channels contain chains of corner-sharing Ti(O,S)₆ octahedra (four Ti1 chains for one Ti2 chain) parallel to the c direction, which are connected by La4 polyhedra (Fig. 1). Note that a similar [La₂S₂] framework (with a rock-salt-type structure) was encountered in the two-dimensional misfit layered chalcogenides (Wiegers et al., 1992), as well as in oxychalcogenides (Meignen et al., 2001; Gardberg et al., 2001).

The title compound is isostructural with Nd₁₆Ti₅S₁₇O₁₇ (Boyer- Candalen et al., 2000). The [La₂S₂] framework is built of two-atom-thick layers with La atoms (La1, La2 and La3) protruding from the plane of S atoms. This structure arises because these La atoms are also bonded to O atoms belonging to the Ti octahedra. A complex atomic arrangement is observed at the intersection of two adjacent [La₂S₂] building blocks. This atomic junction involves La3 polyhedra that are connected by S5 atoms, and this 'knot' of four La3 polyhedra encloses a channel filled with S atoms. By comparison with the structure of the Nd homologue, a third S-atom site (S7) is found in this channel for the La derivative. The filling within this channel corresponds to a higher S content, resulting in a slightly modified chemical composition, La₁₆Ti₅S_{17 + x}O₁₇, with x = 0.75 (9). This difference? led us to consider the existence of (S₂)²⁻ pairing, which would be required for charge balance. Not all combinations of atoms S2, S6, and S7 give a pair with a reasonable S—S bond distance, and the most probable pairing is between two S2 atoms (≈ 2.10 Å). Similar (S₂)²⁻ dianions were also encountered in Sr₆V₉S₂₂O₂ (Litteer et al., 2000). Another difference between the Nd and La analogues concerns the splitting of the Ti2 position. Although a rather high U_eq value for atom Ti2 was also obtained in the case of the Nd compound (although not as high as that for the present La compound), the splitting of this position was not considered. Finally, note that the high U value for atom O5 could also be related to the splitting of the Ti2-atom site. The resulting Ti2—O5 distances range from 1.769 to 2.256 Å. A comparable short Ti—O distance of 1.768 Å was encountered in La₂Ti₂O₇ (Gasperin, 1975).

S2. Experimental

The title compound was obtained as a small number of needle-shaped translucent orange single crystals, as a by-product of a solid-state reaction of a mixture of La₂O₃, La₂S₃, TiO₂ and Ag₂O, in the molar ratio 1:3/2:2:1/2. The reaction was carried out for 160 h at 1273 K in a quartz ampoule sealed in vacuo. After a first heating, the product of the reaction was reground and a small amount of iodine was added to favor crystallization during a second heating.

S3. Refinement

During the refinement, the last positions to be found were those of atoms S2, S6 and S7. The largest residual peak in the Fourier difference map at (0, 1/2, 1/4) (4 d site) was introduced and refined (S2 position). Because the resulting displacement parameter of atom S2 was large and the contact between equivalent S2 positions (c/2 = 2.013 Å) was shorter than the minimum distance for a (S₂)²⁻ pairing (>2.05 Å), the site-occupancy factor for atom S2 was halved. Later, the hypothesis of a more general position for atom S2 [8 g site at (0, 1/2, z), with z ≈ 1/5] very slightly improved the refinement. A subsequent Fourier difference calculation revealed two futher residual peaks at (0, 1/2, 0) and (0.461, 0.043, 0), which were introduced as atoms S6 and S7, respectively. A constraint was initially imposed on the sum of the occupancy factors (S2+S6+S7 = half the occupancy of the 4 d site) for a total of two S atoms without formation of (S₂)²⁻ pairing. In addition, the displacement parameters for atoms S2, S6, and S7 were constrained to be identical. However, the refinement at this stage led to a negative U value for these sites (U_iso= −0.006 Ų). When the constraint on the occupancies was removed, the refinement was improved and yielded a positive U value [0.027 (3) Ų]. Initially, atom Ti2 in the 2 b site, (1/2, 1/2, 0), showed a large value of the U₃₃ component, which led us to change it to a more general 4 e site [(1/2, 1/2, z), with z ≈ 0], with a statistical occupancy of 50%. Under these conditions, the final refinement converged to a R value of 0.0234 and yielded a featureless Fourier difference map [+1.65 e.Å⁻³ at (0.405, 0.241, 0.245) and −1.55 e.Å⁻³ at (1/2, 1/2, 0.377)].

Computing details

Program(s) used to refine structure: (Jana 2000; Petricek & Dusek, 2000); software used to prepare material for publication: (Jana 2000; Petricek & Dusek, 2000).

Figures

Fig. 1. The structure of La16Ti5S17 + xO17, projected on to the ab plane.

hexadecalanthanum pentatitanium heptadecasulfide heptadecaoxide

Crystal data

La16Ti5S17.75O17	Dx = 5.28 Mg m^−3
Mr = 3303.0	Mo Kα radiation, λ = 0.71069 Å
Tetragonal, I4/m	Cell parameters from 21662 reflections
a = 22.633 (3) Å	θ = 3.6–34.9°
c = 4.0252 (8) Å	µ = 17.97 mm^−1
V = 2061.9 (6) Å^3	T = 293 K
Z = 2	Needle, orange
F(000) = 2884	0.12 × 0.02 × 0.02 mm

Data collection

Nonius KappaCCD diffractometer	2028 independent reflections
Horizonally mounted graphite crystal monochromator	1799 reflections with I > 2σ(I)
Detector resolution: 9 pixels mm^-1	Rint = 0.027
CCD, ϕ and ω frames scans	θmax = 32.2°, θmin = 3.6°
Absorption correction: gaussian (Petricek & Dusek, 2000) ?	h = −33→33
Tmin = 0.332, Tmax = 0.727	k = −24→25
4503 measured reflections	l = −6→6

Refinement

Refinement on F	σ w = 1/(σ^2(F) + 0.0004F^2)
R[F^2 > 2σ(F^2)] = 0.023	(Δ/σ)max = 0.004
wR(F^2) = 0.032	Δρmax = 1.64 e Å^−3
S = 1.11	Δρmin = −1.55 e Å^−3
2028 reflections	Extinction correction: B-C type 1 Gaussian isotropic (Becker & Coppens, 1974)
95 parameters	Extinction coefficient: 0.017 (4)

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq	Occ. (<1)
La1	0.759231 (13)	0.408156 (13)	0	0.00842 (8)
La2	0.656946 (13)	0.271533 (13)	0	0.00825 (8)
La3	0.882639 (15)	0.549374 (14)	0	0.01350 (9)
La4	0.613148 (13)	0.412900 (13)	0.5	0.00821 (8)
Ti1	0.74936 (4)	0.53324 (4)	0.5	0.0095 (2)
Ti2	0.5	0.5	0.0605 (9)	0.0124 (11)	0.5
S1	0.51367 (5)	0.39550 (6)	0	0.0116 (3)
S2	0.5	0	0.24 (2)	0.027 (3)	0.239 (11)
S3	0.75500 (6)	0.18604 (6)	0	0.0095 (3)
S4	0.82935 (6)	0.62248 (6)	0.5	0.0105 (3)
S5	0.84779 (6)	0.46270 (6)	0.5	0.0115 (3)
S6	0.5	0	0	0.027 (3)	0.093 (8)
O1	0.69773 (16)	0.59403 (16)	0.5	0.0089 (9)
O2	0.71400 (16)	0.46085 (16)	0.5	0.0091 (9)
O3	0.65915 (16)	0.37787 (16)	0	0.0094 (10)
O4	0.76632 (17)	0.53386 (16)	0	0.0110 (10)
O5	0.5	0.5	0.5	0.045 (3)
S7	0.4618 (5)	0.0453 (4)	0	0.027 (3)	0.152 (6)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
La1	0.00833 (13)	0.00915 (14)	0.00778 (15)	−0.00126 (10)	0	0
La2	0.00891 (14)	0.00760 (13)	0.00824 (15)	−0.00002 (10)	0	0
La3	0.01752 (16)	0.00978 (14)	0.01319 (17)	−0.00077 (12)	0	0
La4	0.00849 (14)	0.00830 (14)	0.00785 (15)	−0.00062 (10)	0	0
Ti1	0.0081 (4)	0.0057 (4)	0.0148 (5)	0.0007 (3)	0	0
Ti2	0.0096 (6)	0.0096 (6)	0.018 (3)	0	0	0
S1	0.0073 (5)	0.0109 (6)	0.0167 (7)	−0.0012 (4)	0	0
S2	0.014 (3)	0.010 (3)	0.056 (7)	−0.005 (3)	0	0
S3	0.0097 (5)	0.0079 (5)	0.0108 (6)	0.0004 (4)	0	0
S4	0.0107 (5)	0.0092 (5)	0.0117 (6)	−0.0006 (4)	0	0
S5	0.0104 (6)	0.0111 (6)	0.0131 (6)	0.0013 (5)	0	0
S6	0.014 (3)	0.010 (3)	0.056 (7)	−0.005 (3)	0	0
O1	0.0062 (15)	0.0110 (16)	0.0095 (17)	0.0013 (13)	0	0
O2	0.0093 (16)	0.0085 (16)	0.0097 (16)	−0.0002 (13)	0	0
O3	0.0096 (16)	0.0083 (16)	0.0101 (18)	0.0003 (13)	0	0
O4	0.0117 (17)	0.0122 (17)	0.0092 (18)	0.0006 (14)	0	0
O5	0.045 (4)	0.045 (4)	0.045 (7)	0	0	0
S7	0.014 (3)	0.010 (3)	0.056 (7)	−0.005 (3)	0	0

Geometric parameters (Å, º)

La1—S3^i	2.9495 (9)	La3—S6^xi	3.5150 (3)
La1—S3^ii	2.9495 (9)	La3—S6^viii	2.8817 (3)
La1—S4^iii	3.2170 (14)	La3—O4	2.656 (4)
La1—S5^iv	3.0971 (10)	La3—S7^vii	2.695 (7)
La1—S5	3.0971 (10)	La3—S7^xi	2.695 (7)
La1—O2^iv	2.554 (2)	La3—S7^ix	2.567 (10)
La1—O2	2.554 (2)	La4—S1	3.0455 (9)
La1—O3	2.366 (4)	La4—S1^xii	3.0455 (9)
La1—O4	2.849 (4)	La4—S1^ix	3.0480 (9)
La2—S3	2.9444 (13)	La4—S1^xiii	3.0480 (9)
La2—S3^i	2.9907 (10)	La4—O1^vi	2.541 (4)
La2—S3^ii	2.9907 (10)	La4—O2	2.527 (4)
La2—S4^v	3.1420 (11)	La4—O3	2.401 (2)
La2—S4^vi	3.1420 (11)	La4—O3^xii	2.401 (2)
La2—O1^v	2.562 (2)	La4—O5	3.2318 (7)
La2—O1^vi	2.562 (2)	Ti1—S4	2.7122 (16)
La2—O3	2.407 (4)	Ti1—S5	2.7406 (16)
La2—O4^vi	2.915 (4)	Ti1—O1	1.805 (4)
La3—S2^vii	3.07 (3)	Ti1—O2	1.824 (4)
La3—S2^ii	3.07 (3)	Ti1—O4	2.0489 (8)
La3—S2^viii	3.04 (3)	Ti1—O4^xii	2.0489 (8)
La3—S2^ix	3.04 (3)	Ti2—S1	2.3977 (14)
La3—S4^iv	2.8711 (10)	Ti2—S1^xiv	2.3977 (14)
La3—S4	2.8711 (10)	Ti2—S1^vi	2.3977 (14)
La3—S5^iv	2.9190 (10)	Ti2—S1^ix	2.3977 (14)
La3—S5	2.9190 (10)	Ti2—O5^iv	2.256 (3)
La3—S5^x	2.9498 (14)	Ti2—O5	1.769 (3)
La3—S6^vii	3.5150 (3)
S3^i—La1—S3^ii	86.06 (2)	S4^iv—La3—S7^xi	145.3 (2)
S3^i—La1—S4^iii	71.95 (3)	S4^iv—La3—S7^ix	135.39 (2)
S3^i—La1—S5^iv	85.15 (3)	S4—La3—S4^iv	89.01 (3)
S3^i—La1—S5	143.34 (4)	S4—La3—S5^iv	139.21 (4)
S3^i—La1—O2^iv	75.88 (7)	S4—La3—S5	77.90 (3)
S3^i—La1—O2	146.26 (9)	S4—La3—S5^x	78.66 (3)
S3^i—La1—O3	71.70 (7)	S4—La3—S6^vii	154.43 (3)
S3^i—La1—O4	136.704 (19)	S4—La3—S6^xi	95.70 (2)
S3^ii—La1—S3^i	86.06 (2)	S4—La3—S6^viii	127.64 (2)
S3^ii—La1—S4^iii	71.95 (3)	S4—La3—O4	70.11 (6)
S3^ii—La1—S5^iv	143.34 (4)	S4—La3—S7^vii	145.3 (2)
S3^ii—La1—S5	85.15 (3)	S4—La3—S7^xi	77.02 (18)
S3^ii—La1—O2^iv	146.26 (9)	S4—La3—S7^ix	135.39 (2)
S3^ii—La1—O2	75.88 (7)	S5^iv—La3—S5	87.18 (3)
S3^ii—La1—O3	71.70 (7)	S5^iv—La3—S5^x	134.13 (2)
S3^ii—La1—O4	136.704 (19)	S5^iv—La3—S6^vii	66.16 (2)
S4^iii—La1—S5^iv	71.49 (3)	S5^iv—La3—S6^xi	112.67 (3)
S4^iii—La1—S5	71.49 (3)	S5^iv—La3—S6^viii	89.34 (3)
S4^iii—La1—O2^iv	126.34 (7)	S5^iv—La3—O4	69.10 (6)
S4^iii—La1—O2	126.34 (7)	S5^iv—La3—S7^vii	69.01 (19)
S4^iii—La1—O3	129.49 (9)	S5^iv—La3—S7^xi	132.2 (2)
S4^iii—La1—O4	120.44 (8)	S5^iv—La3—S7^ix	69.67 (15)
S5^iv—La1—S5	81.06 (2)	S5—La3—S5^iv	87.18 (3)
S5^iv—La1—O2^iv	63.97 (8)	S5—La3—S5^x	134.13 (2)
S5^iv—La1—O2	125.83 (8)	S5—La3—S6^vii	112.67 (3)
S5^iv—La1—O3	137.30 (3)	S5—La3—S6^xi	66.16 (2)
S5^iv—La1—O4	64.25 (6)	S5—La3—S6^viii	89.34 (3)
S5—La1—S5^iv	81.06 (2)	S5—La3—O4	69.10 (6)
S5—La1—O2^iv	125.83 (8)	S5—La3—S7^vii	132.2 (2)
S5—La1—O2	63.97 (8)	S5—La3—S7^xi	69.01 (19)
S5—La1—O3	137.30 (3)	S5—La3—S7^ix	69.67 (15)
S5—La1—O4	64.25 (6)	S5^x—La3—S5^iv	134.13 (2)
O2^iv—La1—O2	104.02 (9)	S5^x—La3—S5	134.13 (2)
O2^iv—La1—O3	75.62 (10)	S5^x—La3—S6^vii	77.68 (2)
O2^iv—La1—O4	63.66 (8)	S5^x—La3—S6^xi	77.68 (2)
O2—La1—O2^iv	104.02 (9)	S5^x—La3—S6^viii	74.91 (3)
O2—La1—O3	75.62 (10)	S5^x—La3—O4	135.50 (8)
O2—La1—O4	63.66 (8)	S5^x—La3—S7^vii	67.6 (2)
O3—La1—O4	110.07 (12)	S5^x—La3—S7^xi	67.6 (2)
S3—La2—S3^i	73.07 (3)	S5^x—La3—S7^ix	102.7 (2)
S3—La2—S3^ii	73.07 (3)	S6^vii—La3—S6^xi	69.861 (6)
S3—La2—S4^v	73.12 (3)	S6^vii—La3—S6^viii	34.931 (3)
S3—La2—S4^vi	73.12 (3)	S6^vii—La3—O4	134.99 (5)
S3—La2—O1^v	126.69 (7)	S6^vii—La3—S7^vii	19.9 (2)
S3—La2—O1^vi	126.69 (7)	S6^vii—La3—S7^xi	85.10 (17)
S3—La2—O3	129.89 (9)	S6^vii—La3—S7^ix	43.49 (12)
S3—La2—O4^vi	121.82 (8)	S6^xi—La3—S6^vii	69.861 (6)
S3^i—La2—S3	73.07 (3)	S6^xi—La3—S6^viii	34.931 (3)
S3^i—La2—S3^ii	84.59 (2)	S6^xi—La3—O4	134.99 (5)
S3^i—La2—S4^v	88.15 (3)	S6^xi—La3—S7^vii	85.10 (17)
S3^i—La2—S4^vi	146.08 (4)	S6^xi—La3—S7^xi	19.9 (2)
S3^i—La2—O1^v	75.79 (7)	S6^xi—La3—S7^ix	43.49 (12)
S3^i—La2—O1^vi	144.28 (8)	S6^viii—La3—S6^vii	34.931 (3)
S3^i—La2—O3	70.44 (7)	S6^viii—La3—S6^xi	34.931 (3)
S3^i—La2—O4^vi	137.00 (2)	S6^viii—La3—O4	149.59 (8)
S3^ii—La2—S3	73.07 (3)	S6^viii—La3—S7^vii	51.28 (17)
S3^ii—La2—S3^i	84.59 (2)	S6^viii—La3—S7^xi	51.28 (17)
S3^ii—La2—S4^v	146.08 (4)	S6^viii—La3—S7^ix	27.8 (2)
S3^ii—La2—S4^vi	88.15 (3)	O4—La3—S7^vii	130.84 (17)
S3^ii—La2—O1^v	144.28 (8)	O4—La3—S7^xi	130.84 (17)
S3^ii—La2—O1^vi	75.79 (7)	O4—La3—S7^ix	121.8 (2)
S3^ii—La2—O3	70.44 (7)	S7^vii—La3—S7^xi	96.6 (2)
S3^ii—La2—O4^vi	137.00 (2)	S7^vii—La3—S7^ix	63.4 (2)
S4^v—La2—S4^vi	79.67 (2)	S7^xi—La3—S7^vii	96.6 (2)
S4^v—La2—O1^v	63.65 (8)	S7^xi—La3—S7^ix	63.4 (2)
S4^v—La2—O1^vi	124.24 (8)	S7^ix—La3—S7^vii	63.4 (2)
S4^v—La2—O3	137.03 (4)	S7^ix—La3—S7^xi	63.4 (2)
S4^v—La2—O4^vi	63.20 (6)	S1—La4—S1^xii	82.73 (2)
S4^vi—La2—S4^v	79.67 (2)	S1—La4—S1^ix	67.23 (3)
S4^vi—La2—O1^v	124.24 (8)	S1—La4—S1^xiii	119.06 (3)
S4^vi—La2—O1^vi	63.65 (8)	S1—La4—O1^vi	75.32 (7)
S4^vi—La2—O3	137.03 (4)	S1—La4—O2	136.32 (3)
S4^vi—La2—O4^vi	63.20 (6)	S1—La4—O3	73.97 (8)
O1^v—La2—O1^vi	103.56 (9)	S1—La4—O3^xii	146.30 (9)
O1^v—La2—O3	74.93 (9)	S1—La4—O5	59.54 (2)
O1^v—La2—O4^vi	63.16 (8)	S1^xii—La4—S1	82.73 (2)
O1^vi—La2—O1^v	103.56 (9)	S1^xii—La4—S1^ix	119.06 (3)
O1^vi—La2—O3	74.93 (9)	S1^xii—La4—S1^xiii	67.23 (3)
O1^vi—La2—O4^vi	63.16 (8)	S1^xii—La4—O1^vi	75.32 (7)
O3—La2—O4^vi	108.28 (12)	S1^xii—La4—O2	136.32 (3)
S2^vii—La3—S2^ii	40 (2)	S1^xii—La4—O3	146.30 (9)
S2^vii—La3—S2^viii	38 (2)	S1^xii—La4—O3^xii	73.97 (8)
S2^vii—La3—S2^ix	2 (2)	S1^xii—La4—O5	59.54 (2)
S2^vii—La3—S4^iv	109.5 (15)	S1^ix—La4—S1	67.23 (3)
S2^vii—La3—S4	144.5 (12)	S1^ix—La4—S1^xii	119.06 (3)
S2^vii—La3—S5^iv	75.7 (11)	S1^ix—La4—S1^xiii	82.65 (2)
S2^vii—La3—S5	103.0 (11)	S1^ix—La4—O1^vi	136.58 (3)
S2^vii—La3—S5^x	75.85 (15)	S1^ix—La4—O2	74.73 (7)
S2^vii—La3—S6^vii	14.9 (16)	S1^ix—La4—O3	73.82 (8)
S2^vii—La3—S6^xi	55.0 (16)	S1^ix—La4—O3^xii	145.95 (9)
S2^vii—La3—S6^viii	20.1 (16)	S1^ix—La4—O5	59.52 (2)
S2^vii—La3—O4	144.1 (8)	S1^xiii—La4—S1	119.06 (3)
S2^vii—La3—S7^vii	32.5 (15)	S1^xiii—La4—S1^xii	67.23 (3)
S2^vii—La3—S7^xi	70.6 (16)	S1^xiii—La4—S1^ix	82.65 (2)
S2^vii—La3—S7^ix	33.8 (9)	S1^xiii—La4—O1^vi	136.58 (3)
S2^ii—La3—S2^vii	40 (2)	S1^xiii—La4—O2	74.73 (7)
S2^ii—La3—S2^viii	2 (2)	S1^xiii—La4—O3	145.95 (9)
S2^ii—La3—S2^ix	38 (2)	S1^xiii—La4—O3^xii	73.82 (8)
S2^ii—La3—S4^iv	144.5 (12)	S1^xiii—La4—O5	59.52 (2)
S2^ii—La3—S4	109.5 (15)	O1^vi—La4—O2	125.23 (12)
S2^ii—La3—S5^iv	103.0 (11)	O1^vi—La4—O3	75.43 (10)
S2^ii—La3—S5	75.7 (11)	O1^vi—La4—O3^xii	75.43 (10)
S2^ii—La3—S5^x	75.85 (15)	O1^vi—La4—O5	117.78 (8)
S2^ii—La3—S6^vii	55.0 (16)	O2—La4—O3	75.53 (10)
S2^ii—La3—S6^xi	14.9 (16)	O2—La4—O3^xii	75.53 (10)
S2^ii—La3—S6^viii	20.1 (16)	O2—La4—O5	116.98 (8)
S2^ii—La3—O4	144.1 (8)	O3—La4—O3^xii	113.93 (10)
S2^ii—La3—S7^vii	70.6 (16)	O3—La4—O5	123.03 (7)
S2^ii—La3—S7^xi	32.5 (15)	O3^xii—La4—O3	113.93 (10)
S2^ii—La3—S7^ix	33.8 (9)	O3^xii—La4—O5	123.03 (7)
S2^viii—La3—S2^vii	38 (2)	S4—Ti1—S5	83.76 (5)
S2^viii—La3—S2^ii	2 (2)	S4—Ti1—O1	82.22 (12)
S2^viii—La3—S2^ix	37 (2)	S4—Ti1—O2	164.17 (13)
S2^viii—La3—S4^iv	143.2 (13)	S4—Ti1—O4	82.53 (11)
S2^viii—La3—S4	111.0 (15)	S4—Ti1—O4^xii	82.53 (11)
S2^viii—La3—S5^iv	101.9 (11)	S5—Ti1—O1	165.98 (13)
S2^viii—La3—S5	76.8 (11)	S5—Ti1—O2	80.41 (12)
S2^viii—La3—S5^x	75.71 (14)	S5—Ti1—O4	81.47 (11)
S2^viii—La3—S6^vii	53.4 (16)	S5—Ti1—O4^xii	81.47 (11)
S2^viii—La3—S6^xi	16.5 (16)	O1—Ti1—O2	113.62 (17)
S2^viii—La3—S6^viii	18.4 (16)	O1—Ti1—O4	96.67 (11)
S2^viii—La3—O4	144.9 (8)	O1—Ti1—O4^xii	96.67 (11)
S2^viii—La3—S7^vii	69.1 (16)	O2—Ti1—O4	95.07 (11)
S2^viii—La3—S7^xi	33.9 (15)	O2—Ti1—O4^xii	95.07 (11)
S2^viii—La3—S7^ix	32.9 (9)	O4—Ti1—O4^xii	158.39 (16)
S2^ix—La3—S2^vii	2 (2)	O4^xii—Ti1—O4	158.39 (16)
S2^ix—La3—S2^ii	38 (2)	S1—Ti2—S1^xiv	168.33 (16)
S2^ix—La3—S2^viii	37 (2)	S1—Ti2—S1^vi	89.41 (4)
S2^ix—La3—S4^iv	111.0 (15)	S1—Ti2—S1^ix	89.41 (4)
S2^ix—La3—S4	143.2 (13)	S1—Ti2—O5^iv	84.17 (8)
S2^ix—La3—S5^iv	76.8 (11)	S1—Ti2—O5	95.83 (8)
S2^ix—La3—S5	101.9 (11)	S1^xiv—Ti2—S1	168.33 (16)
S2^ix—La3—S5^x	75.71 (14)	S1^xiv—Ti2—S1^vi	89.41 (4)
S2^ix—La3—S6^vii	16.5 (16)	S1^xiv—Ti2—S1^ix	89.41 (4)
S2^ix—La3—S6^xi	53.4 (16)	S1^xiv—Ti2—O5^iv	84.17 (8)
S2^ix—La3—S6^viii	18.4 (16)	S1^xiv—Ti2—O5	95.83 (8)
S2^ix—La3—O4	144.9 (8)	S1^vi—Ti2—S1	89.41 (4)
S2^ix—La3—S7^vii	33.9 (15)	S1^vi—Ti2—S1^xiv	89.41 (4)
S2^ix—La3—S7^xi	69.1 (16)	S1^vi—Ti2—S1^ix	168.33 (16)
S2^ix—La3—S7^ix	32.9 (9)	S1^vi—Ti2—O5^iv	84.17 (8)
S4^iv—La3—S4	89.01 (3)	S1^vi—Ti2—O5	95.83 (8)
S4^iv—La3—S5^iv	77.90 (3)	S1^ix—Ti2—S1	89.41 (4)
S4^iv—La3—S5	139.21 (4)	S1^ix—Ti2—S1^xiv	89.41 (4)
S4^iv—La3—S5^x	78.66 (3)	S1^ix—Ti2—S1^vi	168.33 (16)
S4^iv—La3—S6^vii	95.70 (2)	S1^ix—Ti2—O5^iv	84.17 (8)
S4^iv—La3—S6^xi	154.43 (3)	S1^ix—Ti2—O5	95.83 (8)
S4^iv—La3—S6^viii	127.64 (2)	O5^iv—Ti2—O5	180
S4^iv—La3—O4	70.11 (6)	O5—Ti2—O5^iv	180
S4^iv—La3—S7^vii	77.02 (18)

Symmetry codes: (i) −x+3/2, −y+1/2, −z−1/2; (ii) −x+3/2, −y+1/2, −z+1/2; (iii) −y+3/2, x−1/2, −z+1/2; (iv) x, y, z−1; (v) y, −x+1, z−1; (vi) y, −x+1, z; (vii) x+1/2, y+1/2, z−1/2; (viii) y+1, −x+1, z; (ix) −y+1, x, −z; (x) y+1/2, −x+3/2, z−1/2; (xi) x+1/2, y+1/2, z+1/2; (xii) x, y, z+1; (xiii) −y+1, x, −z+1; (xiv) −x+1, −y+1, −z.