Lithium zincopyrophosphate, Li₂Zn₃(P₂O₇)₂

The title compound, dilithium(I) trizinc(II) bis­[diphos­phate(4-)], is the first quaternary lithium zincopyro­phosphate in the Li-Zn-P-O system. It features zigzag chains running along c, which are built up from edge-sharing [ZnO₅] trigonal bipyramids. One of the two independent Zn sites is fully occupied, whereas the other is statistically disordered by Zn²⁺ and Li⁺ cations, although the two Zn sites have similar coordination environments. Li⁺ cations occupy a four-coordinated independent site with an occupancy factor of 0.5, as well as being disordered on the partially occupied five-coordinated Zn site with a Zn²⁺/Li⁺ ratio of 1:1.

S1. Comment

High-quality II–VI semiconductor zinc oxide (ZnO) crystals have various applications in functional devices (Look, 2001; Tsukazaki et al., 2005). Due to the high melting point (2248 K) and serious volatilization of ZnO at high temperature, a suitable flux is needed for growing high-quality ZnO crystals at a lower temperature. The subsolidus phase relations of the ternary system A₂O–ZnO–P₂O₅ (A = Li, Na or K) were systematically investigated to find such a flux. The title compound, Li₂Zn₃(P₂O₇)₂, is a possible new phase in this system and Zn₂P₂O₇ and Li₄P₂O₇ were used to synthesize it. The X-ray powder diffraction pattern was measured on the reaction products and all peaks were indexed using TREOR (Werner et al., 1985), with an orthorhombic unit cell a = 5.191 (1), b = 13.226 (4), c = 16.166 (5) Å [M(20) = 17, F(20) = 27], which indicates that the product is a single phase. This unit cell, being in good agreement with that from single-crystal diffraction, is similar but not identical to the cell parameters of γ-Zn₂P₂O₇ (Bataille et al., 1998). Also, the measured powder diffraction pattern did not match PDF entry 49–1240 (ICDD, 2004) for γ-Zn₂P₂O₇ very well. In addition, the warming, heating and cooling scheme guaranteed that the volatilization of Li, Zn and P was avoided, hence the compositon of the product was not significantly different from the starting materials. Therefore, the product was believed to be Li₂Zn₃(P₂O₇)₂ and single-crystal structure analysis was performed to determine the structure and to verify this new phase. We hereby report the structure of this compound from single-crystal diffraction.

The title compound has two symmetry-independent sites for Zn atoms. One is fully occupied with a trace amount (~0.9%) of Li⁺ contamination, whereas the other is disordered by Zn²⁺ and Li⁺ cations in a Zn²⁺/Li⁺ ratio of 1:1. As shown in Fig. 1, Zn atoms are coordinated by five O atoms, three of which are in the equatorial plane while the other two are on the northern and southern pole, respectively. For the fully occupied Zn sites, the average Zn—O bond length in the equatorial plane is 1.97 (2) Å, while the average Zn—O distance between Zn and the polar O atoms is 2.16 (1) Å. The corresponding values for the partially occupied Zn site are 2.01 (6) and 2.09 (7) Å, respectively. Two fully occupied Zn1—O bipyramids connect to each other by sharing one edge to form a [Zn₂O₈] dimer, and the partially occupied Zn2—O polyhedra build up [Zn₂O₈] dimers in the same fashion (Fig. 2). Fully and partially occupied [Zn₂O₈] dimers share edges alternately to form [ZnO₅] bipyramid chains running along the c axis. The Zn1···Zn1 interatomic distance between the centres of two adjacent fully occupied [ZnO₅] polyhedra is 3.1995 (4) Å, whereas the corresponding Zn2···Zn2 distance for the partially occupied [ZnO₅] polyhedra is 2.857 (1) Å. The Zn1···Zn2 distance between the centres of neighbouring fully and partially occupied [ZnO₅] pyramids is 3.2500 (7) Å. The difference between the Zn1···Zn1 and Zn2···Zn2 distances leads to Zn²⁺/Li⁺ disordering on Zn2 site rather than on both Zn1 and Zn2 sites. The shorter Zn2···Zn2 distance favours lower charges on Zn2 sites, produced by replacing half of the Zn²⁺ cations with the same number of Li⁺ cations, whereas the Zn1 site needs a fully occupied Zn²⁺ ion to stablize the structure. The infinite chains are crosslinked by sharing tetrahedra vertices with [P₂O₇]⁴⁻ pyrophosphate groups to build up the three-dimensional framework structure of Li₂Zn₃(P₂O₇)₂ (Fig. 2). One half of the Li⁺ cations are disordered with Zn²⁺ on the partially occupied Zn2 positions and the other half of the Li⁺cations are situated in the interstitial positions of the framework with an occupancy factor of 1/2, coordinated by four O atoms with an average Li—O distance of 2.0 (1) Å.

The basic structural features of the title compound are very similar to those of γ-Zn₂(P₂O₇) (Bataille et al., 1998). The latter compound also consists of infinite corrugated Zn—O bipyramid chains running along c, which are crosslinked together by pyrophosphate groups to form the crystal structure. The title compound is essentially an Li-doped variant of γ-Zn₂(P₂O₇). The Li₂Zn₃(P₂O₇)₂ phase can be derived from γ-Zn₂(P₂O₇) by replacing half of the Zn²⁺ cations on one of the two symmetry-independent Zn sites with Li⁺ cations, and by doping the same number of Li⁺ cations in the interstatial positions of the structure to balance the net charge due to Zn²⁺–Li⁺ substitution. Similar to the title compound, the Zn···Zn distances in the γ-Zn₂(P₂O₇) structure also fall into two groups of 3.084 and 3.242/3.252 Å, respectively. The former distance (3.084 Å) is significantly longer than the corresponding value [2.857 (1) Å] in the title compound, whereas the values in the second group are comparable with their counterparts in the Li₂Zn₃(P₂O₇)₂ structure. In the γ-Zn₂(P₂O₇) structure, it is the Zn²⁺ cations on the Zn sites involving shorter Zn···Zn distances (3.084 Å) that are partially substituted by Li⁺ cations to form the Li₂Zn₃(P₂O₇)₂ phase.

The structures of several Li–Zn–P–O quaternary compounds have been reported, examples being α-LiZnPO₄ (Elammari & Elouadi, 1989), δ₁-LiZnPO₄ (Jensen et al., 1995), ε-LiZnPO₄ (Bu et al., 1996), LiZnPO₄-CR1 (Bu et al., 1998), and α-Li₄Zn(PO₄)₂ and β-Li₄Zn(PO₄)₂ (Jensen et al., 2002). All these compounds are orthophosphates and all the Zn atoms in these structures are tetrahedrally coordinated by O atoms, with an average Zn—O distance of 1.95 (1) Å. This fact indicates that the Zn²⁺ cation has a strong preference for tetrahedral coordination in Li–Zn–P–O system. However, under the conditions reported in this paper, the Zn²⁺ cations are coordinated by five O atoms to form bipyramids, and these polyhedra build up infinite chains by sharing edges. Pyrophosphate groups, [P₂O₇]⁴⁻, rather than orthophosphate groups, [PO₄]³⁻, are observed in the structure and crosslink the [ZnO₅] bipyramid chains.

The Li⁺ cations in all the reported structures are tetrahedrally coordinated by four O atoms, whether they are situated in the walls of channels (ε-LiZnPO₄), in negatively charged cages (LiZnPO₄-CR1), or disordered with Zn²⁺ cations to a minor degree [δ₁-LiZnPO₄, α-Li₄Zn(PO₄)₂ and β-Li₄Zn(PO₄)₂]. In contrast, the coordination of the Li⁺ cations in the title compound is rather complicated. The interstitial Li⁺ cations are tetrahedrally coordinated, whereas the Li⁺ cations disordered on the Zn sites are five-coordinated. Due to the similarity in the coordination radii of Li⁺ and Zn²⁺ cations, statistical disorder of Li⁺ and Zn²⁺ is possible in principle. In fact, the mean Li—O and Zn—O distances calculated from the reported Li–Zn–P–O compounds are 1.97 (5) and 1.95 (1) Å, respectively. A minor degree of disorder was proposed in β-Li₄Zn(PO₄)₂ (prepared from supercritical water at 875 K) and δ₁-LiZnPO₄ (obtained from solution at 365 K), but in the compounds synthesized by high-temperature solid-state reactions at 973–1275 K, a much higher degree of Li⁺/Zn²⁺ statistical disorder (Li⁺:Zn²⁺ = 1:1) was reported in compounds such as NaLiZnP₂O₇ (Shepelev et al., 2005). Similarly, the title compound was prepared at 1123 K and a consequent 1:1 Li⁺/Zn²⁺ disorder is found. All Li⁺ cations in NaLiZnP₂O₇ are disordered with Zn²⁺ cations, but only half of the Li⁺ cations in the title compound are disordered on the Zn²⁺ sites.

S2. Experimental

Pure Zn₂P₂O₇ and Li₄P₂O₇ were first prepared from analytically pure ZnO, Li₂CO₃ and NH₄H₂PO₄. Zn₂P₂O₇ was synthesized from ZnO and NH₄H₂PO₄. The starting materials were first mixed in a molar ratio of 1:1, ground in an agate mortar and warmed at 773 K for 10 h. The powders were then pressed into a 1–2 mm thick pellet (diameter around 12 mm), heated to 1173 K and sintered at this temperature for 48 h. Li₄P₂O₇ was obtained similarly by mixing Li₂CO₃ and NH₄H₂PO₄ in 2:1 molar ratio, but the sintering temperature and time were 1073 K and 96 h, respectively. These two compounds were then weighed and mixed in a molar ratio of 3:1 and ground in an agate mortar. The mixture was heated to 1193 K in a platinum crucible and held at this temperature for 30 min to make the melt homogeneous. The melt was then cooled to 1093 K at a rate of 1 K h⁻¹, followed by cooling to 693 K at a rate of 20 K h⁻¹, and finally it was quenched to room temperature by switching off the furnace. A suitable single-crystal of size 0.30 × 0.28 × 0.25 mm was selected and mounted on a glass fibre for structure determination, and the remaining products were ground into a powder for phase identification by X-ray powder diffraction and for physical property measurements such as second harmonic generation (SHG). No observable SHG signal was detected.

S3. Refinement

The structure was solved by direct methods implemented in SHELXS97 (Sheldrick, 2008) and refined on F² using the full-matrix method. All atoms were refined anisotropically. Refinement of the site-occupancy factors of Zn1 and Zn2 shows that the Zn1 site is contaminated with a trace amount (~0.9%) of Li⁺ and the Zn2 site is statistically disordered by Li⁺ and Zn²⁺ in a Zn²⁺/Li⁺ ratio of around 1:1. The refined site-occupancy factor of Li1 is also around 0.5. These refined values agree well with the expected composition of the title compound. In the final refinement, the site-occupancy factors of Zn1, Zn2, Li1 and Li2 were fixed, due to the weak scattering power and partial occupancy of the Li⁺ cations. A small change in the Li⁺ occupancy factor does not affect the structure features or refinement results significantly.

Computing details

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures

Fig. 1. The atom-labelling scheme and coordination environments of the title compound. Displacement ellipsoids are drawn at the 50% probability level. Li cations disordered on the Zn sites have been omitted for clarity. [Symmetry codes: (i) −x, −y + 1, −z + 1; (ii) −x + 1, −y + 1, −z + 1; (iii) x − 1, y, −z + 3/2; (iv) −x + 1, y + 1/2, −z + 3/2; (v) x + 1, y, −z + 3/2; (vi) −x + 1, −y + 1, z + 1/2; (vii) x, y, −z + 3/2; (viii) −x + 1, y − 1/2, −z + 3/2; (ix) −x + 2, y − 1/2, −z + 3/2.]

Fig. 2. The structure of the title compound viewed along a, showing the [ZnO5] bipyramid chains and the linkage of the polyhedra.

dilithium(I) trizinc(II) bis[diphosphate(4-)]

Crystal data

Li2Zn3(P2O7)2	F(000) = 1072
Mr = 557.87	Dx = 3.373 Mg m^−3
Orthorhombic, Pbcm	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2c 2b	Cell parameters from 5442 reflections
a = 5.1733 (3) Å	θ = 2.5–33.4°
b = 13.1797 (7) Å	µ = 7.17 mm^−1
c = 16.1108 (9) Å	T = 298 K
V = 1098.48 (11) Å^3	Granular, colourless
Z = 4	0.30 × 0.28 × 0.25 mm

Data collection

Bruker SMART APEX CCD area-detector diffractometer	2135 independent reflections
Radiation source: fine-focus sealed tube	1994 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.022
ω scan at different fixed ϕ positions	θmax = 33.5°, θmin = 2.5°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −8→7
Tmin = 0.115, Tmax = 0.165	k = −19→18
9756 measured reflections	l = −24→19

Refinement

Refinement on F^2	0 restraints
Least-squares matrix: full	Primary atom site location: structure-invariant direct methods
R[F^2 > 2σ(F^2)] = 0.023	Secondary atom site location: difference Fourier map
wR(F^2) = 0.063	w = 1/[σ^2(Fo^2) + (0.0382P)^2 + 0.5572P] where P = (Fo^2 + 2Fc^2)/3
S = 1.05	(Δ/σ)max = 0.003
2135 reflections	Δρmax = 0.55 e Å^−3
126 parameters	Δρmin = −0.46 e Å^−3

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 (Ų)

	x	y	z	Uiso*/Ueq	Occ. (<1)
Zn1	0.40045 (4)	0.551978 (13)	0.583844 (10)	0.01173 (6)
Zn2	1.15622 (15)	0.75848 (5)	0.83867 (4)	0.01006 (11)	0.50
Li2	1.203 (3)	0.7504 (11)	0.8568 (8)	0.031 (3)	0.50
Li1	0.0908 (13)	0.3797 (7)	0.6966 (5)	0.0330 (17)	0.50
P1	0.08948 (7)	0.35767 (3)	0.50417 (2)	0.00889 (8)
P2	0.57046 (10)	0.44940 (4)	0.7500	0.00920 (10)
P3	0.65256 (10)	0.66147 (4)	0.7500	0.00891 (10)
O1	0.3060 (2)	0.43500 (8)	0.49561 (7)	0.0125 (2)
O2	−0.0927 (2)	0.36027 (9)	0.42966 (7)	0.0145 (2)
O3	0.2349 (3)	0.2500	0.5000	0.0113 (3)
O4	−0.0492 (3)	0.36465 (9)	0.58531 (6)	0.0160 (2)
O5	0.4050 (2)	0.45300 (9)	0.67297 (8)	0.0174 (2)
O6	0.7589 (3)	0.54661 (11)	0.7500	0.0123 (3)
O7	0.4941 (2)	0.67266 (8)	0.67131 (7)	0.0157 (2)
O8	0.8905 (3)	0.72789 (13)	0.7500	0.0148 (3)
O9	1.2491 (3)	0.85975 (11)	0.7500	0.0140 (3)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Zn1	0.01255 (10)	0.01216 (10)	0.01048 (10)	0.00154 (6)	0.00004 (5)	0.00059 (5)
Zn2	0.0114 (2)	0.0098 (2)	0.0090 (3)	0.00094 (17)	0.00055 (15)	0.00057 (17)
Li2	0.044 (8)	0.025 (4)	0.023 (6)	0.023 (4)	0.018 (5)	0.015 (4)
Li1	0.018 (3)	0.055 (5)	0.026 (3)	−0.014 (3)	−0.001 (2)	0.008 (3)
P1	0.00906 (16)	0.00845 (15)	0.00916 (15)	−0.00097 (11)	0.00008 (10)	0.00010 (11)
P2	0.0093 (2)	0.0083 (2)	0.0101 (2)	0.00085 (16)	0.000	0.000
P3	0.0089 (2)	0.0089 (2)	0.0089 (2)	−0.00076 (16)	0.000	0.000
O1	0.0130 (5)	0.0115 (4)	0.0129 (5)	−0.0045 (4)	0.0019 (4)	−0.0017 (3)
O2	0.0141 (5)	0.0135 (5)	0.0159 (5)	0.0031 (4)	−0.0062 (4)	−0.0019 (4)
O3	0.0093 (6)	0.0091 (6)	0.0155 (7)	0.000	0.000	0.0006 (5)
O4	0.0197 (5)	0.0137 (5)	0.0147 (5)	−0.0004 (4)	0.0072 (4)	−0.0001 (3)
O5	0.0198 (6)	0.0157 (5)	0.0168 (5)	−0.0045 (4)	−0.0077 (4)	0.0047 (4)
O6	0.0085 (6)	0.0100 (6)	0.0182 (7)	−0.0003 (5)	0.000	0.000
O7	0.0195 (5)	0.0139 (5)	0.0138 (5)	0.0007 (4)	−0.0070 (4)	0.0000 (4)
O8	0.0136 (7)	0.0153 (7)	0.0156 (7)	−0.0058 (5)	0.000	0.000
O9	0.0137 (7)	0.0108 (6)	0.0175 (7)	−0.0033 (5)	0.000	0.000

Geometric parameters (Å, º)

Zn1—O1	2.1532 (11)	P2—O9^ix	1.5059 (15)
Zn1—O1^i	1.9935 (11)	P2—O5^vii	1.5083 (12)
Zn1—O2^ii	1.9799 (11)	P2—O5	1.5083 (12)
Zn1—O5	1.9401 (11)	P2—O6	1.6098 (15)
Zn1—O7	2.1796 (11)	P3—O8	1.5106 (16)
Zn1—Zn1^i	3.1995 (4)	P3—O7^vii	1.5168 (11)
Zn1—Zn2^iii	3.2500 (7)	P3—O7	1.5168 (11)
Zn2—O2^iv	2.1694 (13)	P3—O6	1.6107 (15)
Zn2—O4^v	1.9402 (14)	O1—Zn1^i	1.9935 (11)
Zn2—O7^vi	2.0883 (14)	O2—Li2^x	1.958 (14)
Zn2—O8	2.0230 (12)	O2—Zn1^ii	1.9799 (11)
Zn2—O9	2.0132 (12)	O2—Zn2^x	2.1694 (13)
Zn2—Zn2^vii	2.8572 (14)	O3—P1^xi	1.6076 (8)
Li2—O2^iv	1.958 (14)	O4—Li2^viii	1.942 (15)
Li2—O4^v	1.942 (15)	O4—Zn2^viii	1.9402 (14)
Li2—O7^vi	1.876 (15)	O7—Li2^iii	1.876 (15)
Li2—O9	2.257 (12)	O7—Zn2^iii	2.0883 (14)
Li2—O8	2.381 (14)	O8—Zn2^vii	2.0230 (12)
Li1—O4	1.944 (8)	O8—Li1^v	2.180 (9)
Li1—O5	1.929 (7)	O8—Li1^xii	2.180 (9)
Li1—O9^viii	1.975 (7)	O8—Li2^vii	2.381 (14)
Li1—O8^viii	2.180 (9)	O9—P2^xiii	1.5059 (15)
P1—O4	1.4940 (11)	O9—Li1^v	1.975 (7)
P1—O1	1.5207 (11)	O9—Li1^xii	1.975 (7)
P1—O2	1.5265 (12)	O9—Zn2^vii	2.0132 (12)
P1—O3	1.6076 (8)	O9—Li2^vii	2.257 (12)
O5—Zn1—O2^ii	118.94 (5)	P1—O2—Zn1^ii	126.58 (7)
O5—Zn1—O1^i	121.59 (5)	Li2^x—O2—Zn1^ii	97.7 (4)
O2^ii—Zn1—O1^i	119.45 (5)	P1—O2—Zn2^x	127.49 (7)
O5—Zn1—O1	90.57 (5)	Zn1^ii—O2—Zn2^x	103.02 (5)
O2^ii—Zn1—O1	99.40 (5)	P1^xi—O3—P1	124.19 (10)
O1^i—Zn1—O1	79.08 (5)	P1—O4—Li2^viii	124.7 (4)
O5—Zn1—O7	90.54 (5)	P1—O4—Zn2^viii	130.16 (8)
O2^ii—Zn1—O7	79.84 (5)	P1—O4—Li1	129.4 (2)
O1^i—Zn1—O7	100.54 (5)	Li2^viii—O4—Li1	77.8 (4)
O1—Zn1—O7	178.86 (4)	Zn2^viii—O4—Li1	66.3 (2)
O4^v—Zn2—O9	92.17 (6)	P2—O5—Li1	107.5 (2)
O4^v—Zn2—O8	113.30 (7)	P2—O5—Zn1	129.57 (7)
O9—Zn2—O8	78.06 (6)	Li1—O5—Zn1	118.2 (2)
O4^v—Zn2—O7^vi	132.70 (6)	P2—O6—P3	122.77 (10)
O9—Zn2—O7^vi	96.01 (7)	P3—O7—Li2^iii	133.5 (4)
O8—Zn2—O7^vi	113.98 (7)	P3—O7—Zn2^iii	124.71 (7)
O4^v—Zn2—O2^iv	92.90 (5)	P3—O7—Zn1	126.13 (7)
O9—Zn2—O2^iv	173.68 (7)	Li2^iii—O7—Zn1	93.7 (4)
O8—Zn2—O2^iv	103.32 (6)	Zn2^iii—O7—Zn1	99.17 (5)
O7^vi—Zn2—O2^iv	77.77 (5)	P3—O8—Zn2	132.00 (5)
O7^vi—Li2—O4^v	150.3 (10)	P3—O8—Zn2^vii	132.00 (5)
O7^vi—Li2—O2^iv	88.4 (5)	Zn2—O8—Zn2^vii	89.85 (8)
O4^v—Li2—O2^iv	99.8 (7)	P3—O8—Li1^v	124.6 (2)
O7^vi—Li2—O9	94.6 (6)	Zn2—O8—Li1^v	60.55 (19)
O4^v—Li2—O9	85.1 (5)	Zn2^vii—O8—Li1^v	93.8 (2)
O2^iv—Li2—O9	164.5 (9)	P3—O8—Li1^xii	124.6 (2)
O7^vi—Li2—O8	107.6 (7)	Zn2—O8—Li1^xii	93.8 (2)
O4^v—Li2—O8	99.5 (5)	Zn2^vii—O8—Li1^xii	60.55 (19)
O2^iv—Li2—O8	98.1 (7)	Li1^v—O8—Li1^xii	46.5 (4)
O9—Li2—O8	66.4 (3)	P3—O8—Li2	128.8 (4)
O5—Li1—O4	100.6 (3)	Zn2^vii—O8—Li2	91.4 (4)
O5—Li1—O9^viii	154.6 (5)	Li1^v—O8—Li2	64.5 (4)
O4—Li1—O9^viii	93.2 (3)	Li1^xii—O8—Li2	98.1 (4)
O5—Li1—O8^viii	120.0 (4)	P3—O8—Li2^vii	128.8 (4)
O4—Li1—O8^viii	106.7 (4)	Zn2—O8—Li2^vii	91.4 (4)
O9^viii—Li1—O8^viii	75.2 (3)	Li1^v—O8—Li2^vii	98.1 (4)
O4—P1—O1	113.06 (7)	Li1^xii—O8—Li2^vii	64.5 (4)
O4—P1—O2	112.98 (7)	Li2—O8—Li2^vii	92.6 (8)
O1—P1—O2	111.62 (7)	P2^xiii—O9—Li1^v	116.6 (3)
O4—P1—O3	108.40 (5)	P2^xiii—O9—Li1^xii	116.6 (3)
O1—P1—O3	104.07 (7)	Li1^v—O9—Li1^xii	51.7 (4)
O2—P1—O3	106.02 (5)	P2^xiii—O9—Zn2^vii	131.92 (5)
O9^ix—P2—O5^vii	112.12 (6)	Li1^v—O9—Zn2^vii	100.7 (2)
O9^ix—P2—O5	112.12 (6)	Li1^xii—O9—Zn2^vii	64.3 (3)
O5^vii—P2—O5	110.73 (10)	P2^xiii—O9—Zn2	131.92 (5)
O9^ix—P2—O6	104.42 (9)	Li1^v—O9—Zn2	64.3 (3)
O5^vii—P2—O6	108.57 (5)	Li1^xii—O9—Zn2	100.7 (2)
O5—P2—O6	108.57 (5)	Zn2^vii—O9—Zn2	90.41 (7)
O8—P3—O7^vii	112.58 (6)	P2^xiii—O9—Li2^vii	124.5 (4)
O8—P3—O7	112.58 (6)	Li1^v—O9—Li2^vii	108.9 (5)
O7^vii—P3—O7	113.40 (10)	Li1^xii—O9—Li2^vii	70.1 (5)
O8—P3—O6	105.45 (9)	Zn2—O9—Li2^vii	95.3 (4)
O7^vii—P3—O6	106.01 (5)	P2^xiii—O9—Li2	124.5 (4)
O7—P3—O6	106.01 (5)	Li1^v—O9—Li2	70.1 (5)
P1—O1—Zn1^i	132.61 (7)	Li1^xii—O9—Li2	108.9 (5)
P1—O1—Zn1	125.96 (6)	Zn2^vii—O9—Li2	95.3 (4)
Zn1^i—O1—Zn1	100.92 (5)	Li2^vii—O9—Li2	99.4 (8)
P1—O2—Li2^x	129.4 (5)

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