Ba3[Sn(OH)6][SeO4]2·3H2O, a hydrated 1:2 double salt of barium hexa-hydroxidostannate(IV) and barium selenate(VI).

Single crystals of tribarium hexa-hydroxidostannate(IV) bis-[selenate(VI)] trihydrate, Ba3H12O17Se2Sn or Ba3[Sn(OH)6][SeO4]2·3H2O, prepared from solid BaSnO3 and aqueous Na2[SeO4] solutions have hexa-gonal (P63) symmetry. The structure consists of four different primary building units: a hexa-hydroxidostannate(IV) ion, two different selenate(VI) ions, all three of point group symmetry C 3, and a mono-capped {BaO9}-square anti-prism of point group symmetry C 1. The secondary building units result from three of the barium coordination polyhedra linked together via common edges. While one of the two tetra-hedral voids formed from these trimeric units is filled by one bidentate, chelating μ2-selenate ion, the other one remains unoccupied as the corresponding second selenate ion only acts as a monodentate, μ1-ligand. SBUs are completed by hexa-hydroxidostannate(IV) ions sharing adjacent edges on the uncapped faces of the three, mono-capped square anti-prisms. These SBUs are arranged into layers via common edges on the uncapped, square faces of the {BaO9} coordination polyhedra in a way that the hexa-hydroxidostannate(IV) ions act as linkage between two neighboring layers. © Reuter and Kamaha 2022.

Chemical context

The hexa­hydroxidostannate(IV) ion, [Sn(OH)6]2−, is a well established tin(IV) anion in chemistry (Scholder, 1981 ▸), mineralogy (Strunz & Nickel, 1998 ▸) and even archaeology (Basciano et al. 1998 ▸), although the number of well defined and structurally described compounds is rather low, especially in case of two-valent cations as these compounds are only slightly soluble. In a former paper (Kamaha & Reuter, 2009 ▸), we demonstrated strategies for how to circumvent these difficulties by combining slow anion formation with slow crystallization, mimicking to some extent geochemical crystal formation processes.

Here we present our results on experiments where we offered selenate(VI) anions parallel to the slow formation of hexa­hydroxidostannate(IV) ions, as possible co-anions during crystallization. In a typical experiment we exposed BaSnO3 pellets to a Na2SeO4-solution, resulting after a long period in the formation of colorless, hexa­gonal prisms of Ba3[Sn(OH)6][SeO4]2·3H2O, a hydrated 1:2 double salt of barium hexa­hydroxidostannate(IV), Ba[Sn(OH)6], and barium selenate(VI), Ba[SeO4]. From both compounds, only the structure of the selenate has been described in the literature (Andara et al., 2005 ▸).

Structural commentary

The title compound crystallizes in the non-centrosymmetric, hexa­gonal space group P63 and was refined as an inversion twin, giving a Flack parameter of 0.037 (11). With two formula units in the unit cell, the asymmetric unit consists of 1/3 formula unit: a Ba2+ ion and a water mol­ecule, both in general positions, and two crystallographically independent [SeO4]2− ions and one [Sn(OH)6]2− ion, all three having the point group C 3. In addition to the {BaO9}-coordination polyhedron, these complex anions represent the primary building units, PBUs.

The two crystallographically different Sn–O distances within the hexa­hydroxidostannate(IV) anion (Fig. 1 ▸, Table 1 ▸) are identical within standard deviations [d(Sn1—O1) = 2.052 (2) Å and d(Sn1—O2) = 2.054 (2) Å]. The mean value of 2.053 (2) Å is somewhat shorter than the mean value of 2.060 (10) Å observed in other hexa­hydroxidostannates (Kamaha & Reuter, 2009 ▸), but lies in the observed range of 2.039–2.075 Å. Deviations from the geometry of a regular octa­hedron are better expressed in terms of the bond angles, best described by the non-linearity of the octa­hedron axes, which show bond angles of 178.7 (1)°. All oxygen atoms of the [Sn(OH)6]2− ion coordinate to two different Ba atoms in a μ2-coordination mode, while the hydrogen atoms are involved in hydrogen bonds (Table 2 ▸) with the oxygen atoms O3 and O7 of the two different [SeO4]2− ions.

Figure 1

Ball-and-stick model of the [Sn(OH)6]2− ion with atom numbering of the asymmetric unit and orientation of the threefold rotation axis (blue). With exception of the hydrogen atoms, which are shown as spheres of arbitrary radius, all other atoms are drawn as displacement ellipsoids at the 40% level. Bonds between oxygen and barium are indicated as shortened, two-colored sticks while hydrogen bonds are visualized as dashed lines (red).

Table 1

Selected geometric parameters (Å, °)

Se1—O3	1.634 (2)	Se2—O7	1.633 (2)
Se1—O4	1.654 (4)	Se2—O6	1.648 (4)
O3i—Se1—O3	110.09 (8)	O7i—Se2—O7	111.76 (9)
O3—Se1—O4	108.84 (8)	O7—Se2—O6	107.07 (10)

Symmetry code: (i) .

Table 2

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯O3	0.96	1.86	2.772 (3)	158
O2—H2⋯O7ii	0.96	1.85	2.773 (3)	160
O8—H8A⋯O4	0.96	1.82	2.775 (3)	173
O8—H8B⋯O7iii	0.96	1.98	2.923 (3)	169

Symmetry codes: (ii) ; (iii) .

As a result of their C 3 symmetry, the structural parameters (Table 3 ▸) of both selenate(VI) ions are restricted to those between the two crystallographically different oxygen atoms as one (denoted apical in the following) of them is situated on the threefold rotation axis (O4 in the first selenate, O6 in the second selenate) while the others (hereafter basal) (O3/O7) are in general positions. While the mean value of 1.638 (8) Å over all eight Se—O bond lengths is in excellent agreement with the mean Se—O bond lengths in other selenates [neutron data: d(Se—O) = 1.641 Å, Mg[SeO4]·7H2O, T = 10 K (Fortes & Gutmann, 2014 ▸); d(Se—O) = 1.637 Å, Mg[SeO4] · 9H2O, T = 100 K (Fortes et al. 2015 ▸); X-ray data: d(Se—O) = 1.639 Å, Na2[SeO4]·1.5H2O and Na2[SeO4]·10H2O, T = 100 K (Weil & Bonneau, 2014 ▸), d(Se—O) = 1.639 Å, Mg[SeO4]·6H2O, T = 293 K (Kolitsch, 2002 ▸)] the individual Se—O distances differ significantly, reflecting the different functionality of both kind of oxygen atoms. Bonds to the apical oxygen atoms are considerably longer [1.654 (4), 1.648 (4) Å] than those to the basal ones [1.634 (2), 1.633 (2) Å]. In the first selenate ion, the apical oxygen atom acts as acceptor of three hydrogen bonds, while the corresponding oxygen atom of the second selenate ion coordinates to three barium ions. On the other hand, the three basal oxygen atoms act as acceptor of one hydrogen bond and also perform coordinative bonds, each to a different barium ion, in the first selenate ion while those of the second selenate ion accept two hydrogen bonds. Besides bond-length differences, deviations from the geometry of a regular tetra­hedron result in both selenate ions having bond angles widening between the basal oxygen atoms, giving them the shape of slightly flattened trigonal pyramids rather than strict tetra­hedra (Fig. 2 ▸).

Table 3

Bond lengths (Å) within the mono-capped {BaO9} square anti­prism

Ba1—O3	2.715 (2)	Ba1—O6	2.829 (1)
Ba1—O2	2.737 (2)	Ba1—O8iv	2.880 (2)
Ba1—O1i	2.777 (2)	Ba1—O8i	2.931 (2)
Ba1—O1ii	2.779 (2)	Ba1—O8v	3.106 (3)
Ba1—O2iii	2.782 (2)

Symmetry codes: (i) y, −x + y + 1, z +  ; (ii) x − y + 1, x, z +  ; (iii) −x + y + 1, −x + 2, z; (iv) −x + 2, −y + 1, z +  ; (v) −y + 1, x − y, z.

Figure 2

Ball-and-stick models of the two crystallographically independent [SeO4]2− ions with atom numbering of the asymmetric unit and orientation of the threefold rotation axis (blue). With exception of the hydrogen atoms, which are shown as spheres of arbitrary radius, all other atoms are drawn as displacement ellipsoids at the 40% level. Coordination bonds between oxygen and barium are drawn as shortened, two-colored sticks, hydrogen bonds between oxygen and hydrogen atoms of water mol­ecules and hydroxyl groups are drawn as dashed lines (red).

The coordination sphere of the barium ion consists of nine oxygen atoms: two from water mol­ecules, four from two [Sn(OH)6]2− ions, one from the first selenate ion and two, respectively, from the second selenate ion (Fig. 3 ▸). In summary, this {Ba(μ2-OH)4(H2O)2(μ2-OSe2)2(μ1-OSe1)} coord­ination sphere has the shape of a mono-capped square anti­prism. The uncapped face of this coordination polyhedron only is built up from the oxygen atoms of two hexa­hydroxidostannate ions. Its shape is almost square [maximal angle deviations from rectangular: ±0.6 (1)°, maximal deviation from planarity: ±0.0132 Å, side lengths: 2.7705 (2)–3.1720 (2) Å]. In contrast, the capped face of the square anti­prism consists of oxygen atoms from two water mol­ecules and from basal oxygen atoms of the two different selenate ions. Its shape [maximal deviation from planarity: ±0.0022 (2) Å] is much better described as an acute trapezoid with a longer/shorter base of 4.4606 (2)/3.7164 (2) Å, legs of 3.4108 (2)/3.2331 (2) Å and angles between 103.01 (1) and 78.42 (1)°. The dihedral angle between these planes is 5.64 (1)°. These deviations from a regular square anti­prism are mainly caused by coordination to the selenate ions, as the apical oxygen atom of the second one constitutes the cap of the {BaO9} coordination polyhedron, giving rise to a bidentate-chelating coordination mode of this selenate ion while the first selenate ion only acts as monodentate ligand. Ba—O bond lengths (Table 3 ▸) range from 2.715 (2) to 3.106 (3) Å, mean value 2.837 Å. Bonds between the barium ion and the oxygen atoms of the hexa­hydroxidostannate ions are of comparable lengths [d(Ba-O1/O2) = 2.737 (2)–2.782 (2) Å] as are those between the barium ion and the water mol­ecules [2.880 (2)/2.931 (2) Å]. The longest bond [d(Ba—O7) = 3.106 (3) Å] is between the barium ion and the basal oxygen atom of the second selenate ion, while the shortest one [d(Ba—O3) = 2.715 (2) Å] leads to the basal atom of the first selenate ion.

Figure 3

Ball-and-stick model of the mono-capped, square-prismatic {BaO9} coordination polyhedron. Atom colors and bond design as in Fig. 2 ▸. Symmetry codes: (1) y, 1 − x + y,  + z; (2) 2 − x, 1 − y,  + z; (3) 1 − y, x − y, z; (4) 1 − x + y, 2 − x, z; (5) 1 + x − y, x,  + z.

Supra­molecular features

The inter­action of the four different PBUs is visualized in Fig. 4 ▸. The most prominent part of the resulting secondary building units, SBUs, consists of three {BaO9}-coordination polyhedra related to each other via the threefold rotation axes in Wyckoff position b. These three PBUs are linked together via common edges, each of them composed of the coordinated water mol­ecule and the apical oxygen atom of the second selenate ion. In addition, this selenate ion shares its remaining three, basal oxygen atoms with the three surrounding barium ions, thus filling the tetra­hedral void between the three {BaO9} coordination polyhedra. On the other hand, the opposite void of the trimeric {BaO9} unit is empty, as the first selenate ion only shares its three basal oxygen atoms with the three {BaO9} coordination polyhedra but not the apical one. Each SBU is completed by a hexa­hydroxidostannate(IV) ion sharing one edge with the uncapped face of the mono-capped {BaO9} anti­prisms.

Figure 4

Polyhedral model showing the inter­connection of the PBUs (selenate ions in red, {BaO9} coordination polyhedra in green, [Sn(OH)6]2− ions in gray) and their orientation with respect to the different threefold rotation axes (blue, letter = Wyckoff position) of space group P63. Oxygen atoms (red) and hydrogen atoms (gray) are drawn as spheres of arbitrary radius. Hydrogen bonds are indicated as broken red sticks, visible Ba—O coordinative bonds as shortened, two-colored sticks, and visible Sn—O bonds as shortened, brass-colored sticks. In order to show the linkage of the SBUs and to visualize the trigonal–prismatic void between the hexa­hydroxidostannate ions, one additional {BaO9} coordination polyhedron and one additional [Sn(OH)6]2− ion are also shown.

These secondary building units are linked together with three others, each via a common edge of the uncapped square of the {BaO9} coordination polyhedra. In this way, each {BaO9} coordination polyhedron shares two opposite edges of its square faces with two neighboring barium coordination polyhedra, resulting in a trigonal–prismatic void between the three inter­connected SBUs. All corners of these voids consist of hydroxyl groups from [Sn(OH)6]2− ions with the tin atoms of these PBUs situated on threefold rotation axes in Wyckoff position a.

In summary, the SBUs are arranged in layers perpendicular to the c axis direction (Fig. 5 ▸). The pores within these layers are occupied by selenate ions (Se2) of adjacent layers. These selenate ions are connected with the layer via hydrogen bonds (Table 2 ▸) to the water mol­ecules and hydroxyl groups of the [Sn(OH)6]2− ions, while the latter cross-link adjacent layers.

Figure 5

Polyhedral model showing the aufbau principle of the layers (top view above, side view below) as result of the inter­connection of the SBUs. Polyhedra colors according to Fig. 1 ▸ to 3. Isolated selenate ions (Se2) in the three-sided pores belong to adjacent layers. The corresponding hydrogen bonds are omitted for clarity.

Adjacent layers are rotated through 120° against each other, resulting in a compact crystal packing without any accessible holes, channels or pores (Fig. 6 ▸). To some extent, the complex composition of the title compound expressed by the formula M II 3[X IV(OH)6][Y VIO4]2·3H2O has similarities to those of the mineral thaumasite, Ca3[Si(OH)6][SO4][CO3]·12H2O (Edge & Taylor, 1971 ▸; Effenberger et al., 1983 ▸), also crystallizing in space group P63. In contrast to the title compound, the coordination polyhedron of the earth metal in this mineral is reduced from nine to eight and may be described as a one-face distorted square anti­prism. While the hexa­hydroxidosilicate adopt a similar position as the hexa­hydroxidostannate ion, the two other complex anions of thaumasite are only linked via hydrogen bonds to the trimeric units of {CaO8} polyhedra as these secondary building units are not cross-linked into layers.

Figure 6

Polyhedral model showing the packing of two layers.

Synthesis and crystallization

Single crystals of the title compound were obtained in a long-duration experiment exposing a BaSnO3 (Celest) pellet prepared by heating equimolar amounts of SnO2 and BaO for 40 h at 1688 K to 10 ml of a solution of Na2SeO4 (Fluka) in a rolled rim glass vessel closed with a snap-on lid. Colorless, hexa­gonal prisms occurred after several months in the sludge of the mouldered BaSnO3 pellet.

Refinement details

Crystal data, data collection and structure refinement details are summarized in Table 4 ▸. All H atoms were clearly identified in difference Fourier syntheses. Their positions were modeled with respect to a common O—H distance of 0.96 Å and a bond angle of 104.9° in case of the water mol­ecule before they were fixed and allowed to ride on the corresponding oxygen atoms. Refinement of two common isotropic temperature factors, one for the hydrogen atoms of the hydroxyl groups and one for the hydrogen atoms of the water mol­ecule, allowed us to check the reliability of their positions.

Table 4

Experimental details

Crystal data
Chemical formula	Ba3[Sn(OH)6][SeO4]2·3H2O
M r	972.73
Crystal system, space group	Hexagonal, P63
Temperature (K)	100
a, c (Å)	9.2550 (6), 11.4441 (8)
V (Å3)	848.92 (13)
Z	2
Radiation type	Mo Kα
μ (mm−1)	12.68
Crystal size (mm)	0.21 × 0.14 × 0.12
Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Krause et al., 2015 ▸)
T min, T max	0.314, 0.741
No. of measured, independent and observed [I > 2σ(I)] reflections	112431, 1659, 1653
R int	0.040
(sin θ/λ)max (Å−1)	0.703
Refinement
R[F 2 > 2σ(F 2)], wR(F 2), S	0.008, 0.018, 1.13
No. of reflections	1659
No. of parameters	74
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρmax, Δρmin (e Å−3)	0.54, −0.38
Absolute structure	Refined as an inversion twin
Absolute structure parameter	0.037 (11)

Computer programs: APEX2 and SAINT (Bruker, 2009 ▸), SHELXS97 (Sheldrick 2008 ▸), SHELXL2014/7 (Sheldrick, 2015 ▸), DIAMOND (Brandenburg, 2006 ▸), Mercury (Macrae et al. (2020 ▸) and publCIF(Westrip, 2010 ▸).

Crystal structure: contains datablock(s) I. DOI: 10.1107/S2056989022007198/pk2667sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S2056989022007198/pk2667Isup2.hkl

CCDC reference: 2189782

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

Ba3[Sn(OH)6][SeO4]2·3H2O	Dx = 3.805 Mg m−3
Mr = 972.73	Mo Kα radiation, λ = 0.71073 Å
Hexagonal, P63	Cell parameters from 9633 reflections
a = 9.2550 (6) Å	θ = 2.5–30.6°
c = 11.4441 (8) Å	µ = 12.68 mm−1
V = 848.92 (13) Å3	T = 100 K
Z = 2	Needle, colourless
F(000) = 868	0.21 × 0.14 × 0.12 mm

Bruker APEXII CCD diffractometer	1653 reflections with I > 2σ(I)
φ and ω scans	Rint = 0.040
Absorption correction: multi-scan (SADABS; Krause et al., 2015)	θmax = 30.0°, θmin = 2.5°
Tmin = 0.314, Tmax = 0.741	h = −13→13
112431 measured reflections	k = −13→13
1659 independent reflections	l = −16→16

Refinement on F2	H-atom parameters constrained
Least-squares matrix: full	w = 1/[σ2(Fo2) + (0.0035P)2 + 1.0003P] where P = (Fo2 + 2Fc2)/3
R[F2 > 2σ(F2)] = 0.008	(Δ/σ)max = 0.001
wR(F2) = 0.018	Δρmax = 0.54 e Å−3
S = 1.13	Δρmin = −0.37 e Å−3
1659 reflections	Extinction correction: SHELXL-2014/7 (Sheldrick 2015, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
74 parameters	Extinction coefficient: 0.00210 (7)
1 restraint	Absolute structure: Refined as an inversion twin.
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.037 (11)
Hydrogen site location: difference Fourier map

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.

Refinement. Refined as a 2-component inversion twin.

	x	y	z	Uiso*/Ueq
Ba1	0.85513 (2)	0.67674 (2)	0.76533 (2)	0.00444 (4)
Sn1	1.0000	1.0000	0.51521 (5)	0.00320 (5)
O1	0.9097 (3)	0.7983 (3)	0.4052 (2)	0.0057 (4)
H1	0.8736	0.6914	0.4403	0.030 (7)*
O2	1.1069 (3)	0.9077 (3)	0.6279 (2)	0.0056 (4)
H2	1.1548	0.8586	0.5787	0.030 (7)*
Se1	0.6667	0.3333	0.50722 (5)	0.00388 (9)
Se2	0.6667	0.3333	0.96470 (5)	0.00512 (9)
O6	0.6667	0.3333	0.8207 (3)	0.0072 (7)
O4	0.6667	0.3333	0.3627 (4)	0.0076 (6)
O3	0.7824 (3)	0.5248 (3)	0.55332 (19)	0.0108 (4)
O7	0.6848 (3)	0.1745 (3)	1.0066 (2)	0.0106 (4)
O8	0.9600 (3)	0.4949 (2)	0.23440 (18)	0.0095 (4)
H8A	0.8628	0.4361	0.2827	0.054 (11)*
H8B	0.9175	0.4875	0.1568	0.054 (11)*

	U11	U22	U33	U12	U13	U23
Ba1	0.00500 (6)	0.00347 (6)	0.00436 (6)	0.00175 (5)	−0.00001 (8)	−0.00006 (8)
Sn1	0.00351 (7)	0.00351 (7)	0.00258 (10)	0.00175 (3)	0.000	0.000
O1	0.0070 (11)	0.0036 (11)	0.0054 (10)	0.0018 (9)	0.0002 (8)	−0.0001 (8)
O2	0.0062 (11)	0.0066 (11)	0.0057 (10)	0.0044 (10)	0.0001 (8)	0.0009 (8)
Se1	0.00407 (14)	0.00407 (14)	0.0035 (2)	0.00204 (7)	0.000	0.000
Se2	0.00486 (14)	0.00486 (14)	0.0057 (2)	0.00243 (7)	0.000	0.000
O6	0.0085 (10)	0.0085 (10)	0.0046 (17)	0.0043 (5)	0.000	0.000
O4	0.0103 (10)	0.0103 (10)	0.0023 (13)	0.0051 (5)	0.000	0.000
O3	0.0137 (11)	0.0049 (10)	0.0087 (9)	0.0008 (8)	−0.0013 (8)	−0.0022 (8)
O7	0.0133 (11)	0.0089 (10)	0.0125 (9)	0.0077 (9)	−0.0017 (9)	0.0024 (8)
O8	0.0071 (8)	0.0113 (9)	0.0096 (10)	0.0041 (7)	0.0001 (7)	0.0006 (7)

Ba1—O3	2.715 (2)	O1—Ba1ix	2.777 (2)
Ba1—O2	2.737 (2)	O1—Ba1viii	2.779 (2)
Ba1—O1i	2.777 (2)	O1—H1	0.9600
Ba1—O1ii	2.779 (2)	O2—Ba1vii	2.782 (2)
Ba1—O2iii	2.782 (2)	O2—H2	0.9600
Ba1—O6	2.829 (1)	Se1—O3xi	1.633 (2)
Ba1—O8iv	2.880 (2)	Se1—O3	1.634 (2)
Ba1—O8i	2.931 (2)	Se1—O3v	1.634 (2)
Ba1—O7v	3.106 (3)	Se1—O4	1.654 (4)
Ba1—Se2	3.5786 (4)	Se2—O7xi	1.633 (2)
Ba1—Sn1vi	3.8620 (5)	Se2—O7v	1.633 (2)
Ba1—Sn1	3.8639 (5)	Se2—O7	1.633 (2)
Sn1—O1iii	2.052 (2)	Se2—O6	1.648 (4)
Sn1—O1	2.052 (2)	Se2—Ba1xi	3.5786 (4)
Sn1—O1vii	2.052 (2)	Se2—Ba1v	3.5786 (4)
Sn1—O2	2.054 (2)	O6—Ba1xi	2.8288 (8)
Sn1—O2vii	2.054 (2)	O6—Ba1v	2.8288 (8)
Sn1—O2iii	2.054 (2)	O7—Ba1xi	3.106 (3)
Sn1—Ba1viii	3.8620 (5)	O8—Ba1xii	2.880 (2)
Sn1—Ba1ix	3.8620 (5)	O8—Ba1ix	2.931 (2)
Sn1—Ba1x	3.8620 (5)	O8—H8A	0.9600
Sn1—Ba1vii	3.8639 (5)	O8—H8B	0.9600
Sn1—Ba1iii	3.8639 (5)
O3—Ba1—O2	77.58 (7)	Ba1viii—Sn1—Ba1ix	71.188 (11)
O3—Ba1—O1i	142.66 (7)	O1iii—Sn1—Ba1x	43.99 (7)
O2—Ba1—O1i	99.65 (6)	O1—Sn1—Ba1x	94.36 (7)
O3—Ba1—O1ii	144.19 (7)	O1vii—Sn1—Ba1x	43.93 (7)
O2—Ba1—O1ii	70.22 (5)	O2—Sn1—Ba1x	137.27 (7)
O1i—Ba1—O1ii	60.66 (10)	O2vii—Sn1—Ba1x	86.69 (7)
O3—Ba1—O2iii	77.32 (7)	O2iii—Sn1—Ba1x	135.94 (6)
O2—Ba1—O2iii	60.20 (10)	Ba1viii—Sn1—Ba1x	71.188 (11)
O1i—Ba1—O2iii	69.60 (5)	Ba1ix—Sn1—Ba1x	71.188 (11)
O1ii—Ba1—O2iii	99.11 (6)	O1iii—Sn1—Ba1	136.01 (7)
O3—Ba1—O6	76.38 (9)	O1—Sn1—Ba1	85.66 (7)
O2—Ba1—O6	144.30 (7)	O1vii—Sn1—Ba1	136.07 (7)
O1i—Ba1—O6	115.84 (7)	O2—Sn1—Ba1	42.73 (7)
O1ii—Ba1—O6	123.39 (8)	O2vii—Sn1—Ba1	93.29 (7)
O2iii—Ba1—O6	134.70 (7)	O2iii—Sn1—Ba1	44.06 (6)
O3—Ba1—O8iv	70.52 (6)	Ba1viii—Sn1—Ba1	108.832 (5)
O2—Ba1—O8iv	81.46 (7)	Ba1ix—Sn1—Ba1	108.833 (5)
O1i—Ba1—O8iv	146.58 (6)	Ba1x—Sn1—Ba1	179.974 (12)
O1ii—Ba1—O8iv	89.23 (6)	O1iii—Sn1—Ba1vii	136.08 (7)
O2iii—Ba1—O8iv	134.31 (6)	O1—Sn1—Ba1vii	136.01 (7)
O6—Ba1—O8iv	67.08 (4)	O1vii—Sn1—Ba1vii	85.66 (7)
O3—Ba1—O8i	74.22 (6)	O2—Sn1—Ba1vii	44.06 (6)
O2—Ba1—O8i	127.90 (6)	O2vii—Sn1—Ba1vii	42.73 (7)
O1i—Ba1—O8i	79.11 (7)	O2iii—Sn1—Ba1vii	93.29 (7)
O1ii—Ba1—O8i	139.10 (6)	Ba1viii—Sn1—Ba1vii	179.974 (12)
O2iii—Ba1—O8i	71.31 (7)	Ba1ix—Sn1—Ba1vii	108.832 (5)
O6—Ba1—O8i	66.39 (4)	Ba1x—Sn1—Ba1vii	108.832 (5)
O8iv—Ba1—O8i	126.49 (7)	Ba1—Sn1—Ba1vii	71.147 (11)
O3—Ba1—O7v	126.88 (6)	O1iii—Sn1—Ba1iii	85.66 (7)
O2—Ba1—O7v	136.68 (7)	O1—Sn1—Ba1iii	136.07 (7)
O1i—Ba1—O7v	80.61 (7)	O1vii—Sn1—Ba1iii	136.01 (7)
O1ii—Ba1—O7v	72.68 (6)	O2—Sn1—Ba1iii	93.29 (7)
O2iii—Ba1—O7v	148.89 (7)	O2vii—Sn1—Ba1iii	44.06 (6)
O6—Ba1—O7v	52.54 (8)	O2iii—Sn1—Ba1iii	42.73 (7)
O8iv—Ba1—O7v	76.42 (6)	Ba1viii—Sn1—Ba1iii	108.832 (5)
O8i—Ba1—O7v	94.97 (6)	Ba1ix—Sn1—Ba1iii	179.974 (12)
O3—Ba1—Se2	103.02 (5)	Ba1x—Sn1—Ba1iii	108.832 (5)
O2—Ba1—Se2	155.03 (5)	Ba1—Sn1—Ba1iii	71.147 (11)
O1i—Ba1—Se2	94.54 (5)	Ba1vii—Sn1—Ba1iii	71.147 (11)
O1ii—Ba1—Se2	99.78 (5)	Sn1—O1—Ba1ix	105.23 (9)
O2iii—Ba1—Se2	144.71 (5)	Sn1—O1—Ba1viii	105.15 (10)
O6—Ba1—Se2	26.66 (7)	Ba1ix—O1—Ba1viii	108.03 (8)
O8iv—Ba1—Se2	75.44 (4)	Sn1—O1—H1	117.0
O8i—Ba1—Se2	74.87 (4)	Ba1ix—O1—H1	104.7
O7v—Ba1—Se2	27.11 (4)	Ba1viii—O1—H1	115.9
O3—Ba1—Sn1vi	164.39 (5)	Sn1—O2—Ba1	106.66 (10)
O2—Ba1—Sn1vi	89.44 (5)	Sn1—O2—Ba1vii	105.06 (9)
O1i—Ba1—Sn1vi	30.84 (5)	Ba1—O2—Ba1vii	109.09 (8)
O1ii—Ba1—Sn1vi	30.85 (5)	Sn1—O2—H2	105.1
O2iii—Ba1—Sn1vi	88.77 (5)	Ba1—O2—H2	112.5
O6—Ba1—Sn1vi	118.99 (7)	Ba1vii—O2—H2	117.6
O8iv—Ba1—Sn1vi	116.51 (4)	O3xi—Se1—O3	110.09 (8)
O8i—Ba1—Sn1vi	108.24 (4)	O3xi—Se1—O3v	110.09 (8)
O7v—Ba1—Sn1vi	68.67 (4)	O3—Se1—O3v	110.09 (8)
Se2—Ba1—Sn1vi	92.415 (12)	O3xi—Se1—O4	108.84 (8)
O3—Ba1—Sn1	68.85 (5)	O3—Se1—O4	108.84 (8)
O2—Ba1—Sn1	30.61 (5)	O3v—Se1—O4	108.84 (8)
O1i—Ba1—Sn1	89.73 (5)	O7xi—Se2—O7v	111.76 (9)
O1ii—Ba1—Sn1	89.69 (5)	O7xi—Se2—O7	111.76 (9)
O2iii—Ba1—Sn1	30.89 (5)	O7v—Se2—O7	111.76 (9)
O6—Ba1—Sn1	144.71 (7)	O7xi—Se2—O6	107.07 (10)
O8iv—Ba1—Sn1	105.32 (4)	O7v—Se2—O6	107.07 (10)
O8i—Ba1—Sn1	97.70 (4)	O7—Se2—O6	107.07 (10)
O7v—Ba1—Sn1	162.33 (4)	O7xi—Se2—Ba1xi	139.72 (9)
Se2—Ba1—Sn1	170.516 (10)	O7v—Se2—Ba1xi	107.28 (9)
Sn1vi—Ba1—Sn1	95.571 (6)	O7—Se2—Ba1xi	60.11 (9)
O1iii—Sn1—O1	86.27 (10)	O6—Se2—Ba1xi	50.387 (8)
O1iii—Sn1—O1vii	86.27 (10)	O7xi—Se2—Ba1v	60.11 (9)
O1—Sn1—O1vii	86.27 (10)	O7v—Se2—Ba1v	139.72 (9)
O1iii—Sn1—O2	178.66 (12)	O7—Se2—Ba1v	107.28 (9)
O1—Sn1—O2	93.93 (9)	O6—Se2—Ba1v	50.387 (8)
O1vii—Sn1—O2	95.06 (9)	Ba1xi—Se2—Ba1v	83.696 (12)
O1iii—Sn1—O2vii	95.07 (9)	O7xi—Se2—Ba1	107.28 (9)
O1—Sn1—O2vii	178.66 (12)	O7v—Se2—Ba1	60.11 (9)
O1vii—Sn1—O2vii	93.93 (9)	O7—Se2—Ba1	139.72 (9)
O2—Sn1—O2vii	84.73 (10)	O6—Se2—Ba1	50.387 (8)
O1iii—Sn1—O2iii	93.93 (9)	Ba1xi—Se2—Ba1	83.697 (12)
O1—Sn1—O2iii	95.06 (9)	Ba1v—Se2—Ba1	83.696 (12)
O1vii—Sn1—O2iii	178.66 (12)	Se2—O6—Ba1xi	102.95 (7)
O2—Sn1—O2iii	84.73 (10)	Se2—O6—Ba1v	102.95 (7)
O2vii—Sn1—O2iii	84.73 (10)	Ba1xi—O6—Ba1v	115.13 (5)
O1iii—Sn1—Ba1viii	43.93 (7)	Se2—O6—Ba1	102.95 (7)
O1—Sn1—Ba1viii	44.00 (7)	Ba1xi—O6—Ba1	115.13 (5)
O1vii—Sn1—Ba1viii	94.36 (7)	Ba1v—O6—Ba1	115.13 (5)
O2—Sn1—Ba1viii	135.94 (6)	Se1—O3—Ba1	135.14 (12)
O2vii—Sn1—Ba1viii	137.27 (7)	Se2—O7—Ba1xi	92.78 (11)
O2iii—Sn1—Ba1viii	86.69 (7)	Ba1xii—O8—Ba1ix	110.53 (7)
O1iii—Sn1—Ba1ix	94.36 (7)	Ba1xii—O8—H8A	105.3
O1—Sn1—Ba1ix	43.93 (7)	Ba1ix—O8—H8A	119.5
O1vii—Sn1—Ba1ix	43.99 (7)	Ba1xii—O8—H8B	114.2
O2—Sn1—Ba1ix	86.69 (7)	Ba1ix—O8—H8B	102.6
O2vii—Sn1—Ba1ix	135.94 (6)	H8A—O8—H8B	105.0
O2iii—Sn1—Ba1ix	137.27 (7)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···O3	0.96	1.86	2.772 (3)	158
O2—H2···O7xii	0.96	1.85	2.773 (3)	160
O8—H8A···O4	0.96	1.82	2.775 (3)	173
O8—H8B···O7xiii	0.96	1.98	2.923 (3)	169