SrNi3(P2O7)2

inorganic papers

i30

Michael Bolte SrNi₃(P₂O₇)₂ DOI: 101107/S1600536801005700 Acta Cryst.(2001). E57, i30±i31

Acta Crystallographica Section E Structure Reports Online

ISSN 1600-5368

SrNi3(P2O7)2

Michael Bolte

Institut fuÈr Organische Chemie, J. W. Goethe-UniversitaÈt Frankfurt, Marie-Curie-Straûe 11, 60439 Frankfurt/Main, Germany

Correspondence e-mail: [email protected]

Key indicators

Single-crystal X-ray study T= 173 K

Mean(P±O) = 0.001 AÊ Rfactor = 0.021 wRfactor = 0.054

Data-to-parameter ratio = 20.0

For details of how these key indicators were automatically derived from the article, see http://journals.iucr.org/e.

#2001 International Union of Crystallography Printed in Great Britain ± all rights reserved

The title compound, strontium trinickel bis(diphosphate), SrNi3(P2O7)2, is isostructural with all other mixed metal pyrophosphates having the same stoichiometry. The Sr and one of the Ni ions are located on a crystallographic centre of inversion.

Comment

Pyrophosphates are of interest because of their complex network architecture and several structures have been previously determined. The title compound, SrNi3(P2O7)2 (Fig. 1), has already been investigated by powder diffraction (El-Bali, 1993), but since its single-crystal structure has not been determined yet, it is presented here.

The Sr and one of the Ni ions are located on a crystal-lographic centre of inversion. All other atoms occupy general positions. The structure consists of in®nite zigzag chains of NiO6 octahedra sharing either trans or skew edges. These chains are connected by P2O7 moieties to form a three-dimensional network into which the Sr ions are incorporated

viaconnections to eight O atoms (Table 1). The structure of SrNi3(P2O7)2 is isostructural with all other metal pyrophos-phates having the same stoichiometry: Ni3Pb(P2O7)2 (Kras-nikov et al., 1985), CaNi3(P2O7)2, CaCo3(P2O7)2 and SrFe3(P2O7)2 (Lii et al., 1993), and PbCo3(P2O7)2 and PbFe3(P2O7)2(Elmarzoukiet al., 1995).

Experimental

A mixture of (NH4)2HPO4, Sr(OH)2and NiCl2was ground together

and heated to approximately 800 K. The molten mass was maintained at this temperature for two days and then cooled down to room temperature (El-Bali, 1993).

Crystal data

SrNi3(P2O7)2

Mr= 611.63

Monoclinic,P21/c

a= 7.4116 (4) AÊ

b= 7.6542 (3) AÊ

c= 9.4486 (6) AÊ

= 112.194 (5)

V= 496.30 (5) AÊ3

Z= 2

Dx= 4.093 Mg mÿ3

MoKradiation

Cell parameters from 39700 re¯ections

= 3.8±37.3

= 11.69 mmÿ1

T= 173 (2) K Block, yellow 0.240.180.16 mm

Data collection

Stoe IPDS II two-circle diffract-ometer

!scans

Absorption correction: empirical (MULABS; Spek, 1990; Blessing, 1995)

Tmin= 0.101,Tmax= 0.156

26 742 measured re¯ections

2076 independent re¯ections 2027 re¯ections withI> 2(I)

Rint= 0.052 max= 34.3

h=ÿ11!11

k=ÿ12!10

l=ÿ14!14

Re®nement

Re®nement onF2

R[F2_{> 2(F}2_{)] = 0.021}

wR(F2_{) = 0.054}

S= 1.13 2076 re¯ections 104 parameters

w= 1/[2_(F

o2) + (0.0304P)2

+ 0.4865P]

whereP= (Fo2+ 2Fc2)/3

(/)max= 0.001

max= 0.78 e AÊÿ3

min=ÿ0.78 e AÊÿ3

Extinction correction:SHELXL97 Extinction coef®cient: 0.096 (2)

Table 1

Selected bond lengths (AÊ).

Sr1ÐO7 2.5453 (12)

Sr1ÐO2i _{2.6234 (13)}

Sr1ÐO3ii _{2.6541 (13)}

Sr1ÐO1iii _{2.7169 (13)}

Ni1ÐO6iv _{2.0415 (12)}

Ni1ÐO5v _{2.0606 (12)}

Ni1ÐO2vi _{2.0841 (12)}

Ni1ÐO1 2.0901 (13)

Ni1ÐO3ii _{2.1961 (12)}

Ni2ÐO6ii _{2.0458 (12)}

Ni2ÐO7vii _{2.0552 (12)}

Ni2ÐO3ii _{2.1163 (12)}

Symmetry codes: (i) x;1‡y;z; (ii) 1ÿx;1

2‡y;12ÿz; (iii) x;32ÿy;zÿ12; (iv) xÿ1;3

2ÿy;zÿ12; (v)xÿ1;y;z; (vi) 1ÿx;1ÿy;ÿz; (vii) 1ÿx;2ÿy;ÿz.

Data collection:X-AREA(Stoe & Cie, 2001); cell re®nement: X-AREA; data reduction:X-AREA; program(s) used to solve structure:

SHELXS97 (Sheldrick, 1990); program(s) used to re®ne structure:

SHELXL97 (Sheldrick, 1997); molecular graphics: XP in

SHELXTL-Plus(Sheldrick, 1991).

I thank Dr B. El-Bali (University of FeÁs, Morocco) for providing the sample.

References

Blessing, R. H. (1995).Acta Cryst.A51, 33±38.

El-Bali, B. (1993). PhD thesis, Universite Mohammad V, Rabat, Morocco.

Elmarzouki, A., Boukhari, A., Berrada, A. & Holt, E. M. (1995).J. Solid State Chem.118, 202±205.

Krasnikov, V. V., Konstant, Z. A. & Bel'skij, V. K. (1985).Izv. Akad. Nauk SSSR Neorg. Mater.9, 1560±1563.

Lii, K.-H., Shih, P.-F. & Chen, T.-M. (1993).Inorg. Chem.32, 4373±4377. Sheldrick, G. M. (1990).Acta Cryst.A46, 467±473.

Sheldrick, G. M. (1991).SHELXTL-Plus.Release 4.1. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.

Sheldrick, G. M. (1997).SHELXL97. University of GoÈttingen, Germany. Spek, A. L. (1990).Acta Cryst.A46, C-34.

Stoe & Cie (2001).X-AREA.Stoe & Cie, Darmstadt, Germany.

Figure 1

A perspective view of the title compound with the atom-numbering scheme. Displacement ellipsoids are at the 50% probability level. Symmetry operators: (A) 1ÿx, y+1

2,12ÿz; (B)x,32ÿy, zÿ12; (C)x, y+ 1, z; (D) 1ÿx, 1ÿy, z; (E) 1ÿx, 2ÿy, ÿz; (F) xÿ1, y, z; (G)xÿ1,3

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Acta Cryst. (2001). E57, i30–i31

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Acta Cryst. (2001). E57, i30–i31 [doi:10.1107/S1600536801005700]

SrNi

3

(P

2

O

7

)

2

Michael Bolte

S1. Comment

Pyrophosphates are of interest because of their complex network architecture and several structures have been previously

determined. The title compound, SrNi3(P2O7)2, has already been investigated by powder diffraction (El-Bali, 1993), but

since its single-crystal structure has not been determined yet, it is presented here.

The Sr and one of the Ni ions are located on a crystallographic centre of inversion. All other atoms occupy general

positions. The structure consists of infinite zigzag chains of NiO6 octahedra sharing either trans or skew edges. These

chains are connected by P2O7 moieties to form a three-dimensional network into which the Sr ions are incorporated via

connections to eight O atoms. The structure of SrNi3(P2O7)2 is isostructural with all other metal pyrophosphates having

the same stoichiometry: Ni3Pb(P2O7)2 (Krasnikov et al., 1985), CaNi3(P2O7)2, CaCo3(P2O7)2 and SrFe3(P2O7)2 (Lii et al.,

1993), and PbCo3(P2O7)2 and PbFe3(P2O7)2 (Elmarzouki et al., 1995).

S2. Experimental

A mixture of (NH4)2HPO4, Sr(OH)2 and NiCl2 was ground together and heated to approximately 800 K. The molten mass

[image:4.610.126.483.71.329.2]

Figure 1

A perspective view of the title compound with the atom-numbering scheme. Displacement ellipsoids are at the 50%

probability level. Symmetry operators: (A) 1 - x, y + 0.5, 0.5 - z; (B) x, 1.5 - y, z - 0.5; (C) x, y + 1, z; (D) 1 - x, 1 - y, z;

(E) 1 - x, 2 - y, -z; (F) x - 1, y, z; (G) x - 1, 1.5 - y, 0.5 - z.

Strontium trinickel bis(diphosphate)

Crystal data

SrNi3(P2O7)2

Mr = 611.63 Monoclinic, P21/c

a = 7.4116 (4) Å

b = 7.6542 (3) Å

c = 9.4486 (6) Å

β = 112.194 (5)°

V = 496.30 (5) Å3

Z = 2

F(000) = 588

Dx = 4.093 Mg m−3

Mo Kα radiation, λ = 0.71073 Å Cell parameters from 39700 reflections

θ = 3.8–37.3°

µ = 11.69 mm−1

T = 173 K Block, yellow

0.24 × 0.18 × 0.16 mm

Data collection

Stoe IPDS II two-circle diffractometer

Radiation source: fine-focus sealed tube Graphite monochromator

ω scans

Absorption correction: empirical (using intensity measurements)

(MULABS; Spek, 1990; Blessing, 1995)

Tmin = 0.101, Tmax = 0.156

26742 measured reflections 2076 independent reflections 2027 reflections with I > 2σ(I)

Rint = 0.052

θmax = 34.3°, θmin = 4.0°

h = −11→11

k = −12→10

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Acta Cryst. (2001). E57, i30–i31

Refinement

Refinement on F2 Least-squares matrix: full

R[F2 _{> 2σ(F}2_{)] = 0.021}

wR(F2_{) = 0.054}

S = 1.13 2076 reflections 104 parameters 0 restraints

Primary atom site location: structure-invariant direct methods

Secondary atom site location: difference Fourier map

w = 1/[σ2_(F

o2) + (0.0304P)2 + 0.4865P] where P = (Fo2 + 2Fc2)/3

(Δ/σ)max = 0.001 Δρmax = 0.78 e Å−3 Δρmin = −0.78 e Å−3

Extinction correction: SHELXL97, Fc*_{=kFc[1+0.001xFc}2_λ3_/sin(2θ)]-1/4 Extinction coefficient: 0.096 (2)

Special details

Experimental. ;

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 F}2_, conventional R-factors R are based on F, with F set to zero for negative F2_{. The threshold expression of F}2 _{> σ(F}2_{) is used} only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2₎

x y z Uiso*/Ueq

Sr1 0.5000 1.0000 0.0000 0.01074 (7)

Ni1 0.18424 (3) 0.62596 (3) 0.02578 (2) 0.00958 (7)

Ni2 0.0000 1.0000 0.0000 0.00934 (7)

P1 0.60256 (6) 0.44098 (5) 0.20097 (4) 0.00920 (8)

P2 0.88811 (6) 0.70400 (5) 0.19372 (4) 0.00911 (8)

O1 0.39757 (18) 0.47873 (17) 0.19242 (14) 0.0113 (2)

O2 0.62427 (18) 0.31912 (17) 0.08281 (14) 0.01178 (19)

O3 0.73161 (18) 0.38239 (16) 0.36484 (14) 0.01116 (19)

O4 0.67992 (17) 0.62943 (16) 0.17742 (14) 0.0112 (2)

O5 0.97336 (18) 0.57480 (16) 0.11291 (14) 0.01094 (19)

O6 0.99820 (18) 0.71065 (16) 0.36620 (13) 0.01111 (19)

O7 0.84443 (18) 0.87709 (16) 0.11085 (14) 0.0112 (2)

Atomic displacement parameters (Å2₎

U11 _U22 _U33 _U12 _U13 _U23

Sr1 0.01043 (10) 0.01129 (10) 0.01150 (10) −0.00001 (6) 0.00528 (7) 0.00012 (6) Ni1 0.00949 (10) 0.00950 (10) 0.01023 (10) 0.00014 (6) 0.00425 (7) 0.00016 (6) Ni2 0.00950 (13) 0.00890 (13) 0.01007 (12) 0.00003 (8) 0.00420 (10) 0.00001 (8) P1 0.00881 (16) 0.00958 (16) 0.00973 (16) −0.00004 (12) 0.00408 (12) 0.00005 (12) P2 0.00937 (15) 0.00872 (15) 0.00969 (15) −0.00011 (12) 0.00413 (12) 0.00005 (12)

O1 0.0095 (4) 0.0126 (5) 0.0128 (5) 0.0006 (4) 0.0051 (4) 0.0010 (4)

O2 0.0124 (5) 0.0120 (5) 0.0119 (4) −0.0005 (4) 0.0055 (4) −0.0019 (4)

O4 0.0092 (4) 0.0106 (5) 0.0138 (5) −0.0014 (4) 0.0046 (4) 0.0005 (4) O5 0.0118 (5) 0.0103 (4) 0.0120 (4) 0.0001 (4) 0.0059 (4) −0.0009 (4) O6 0.0125 (5) 0.0103 (5) 0.0098 (4) −0.0007 (4) 0.0033 (4) −0.0004 (3)

O7 0.0116 (5) 0.0104 (5) 0.0125 (4) 0.0004 (4) 0.0055 (4) 0.0013 (4)

Geometric parameters (Å, º)

Sr1—O7 2.5453 (12) Ni2—O3vi _{2.1164 (12)}

Sr1—O7i _{2.5453 (12) Ni2—Sr1}vii _{3.7058 (2)}

Sr1—O2ii _{2.6234 (13) P1—O2 1.5094 (13)}

Sr1—O2iii _{2.6234 (13) P1—O1 1.5184 (13)}

Sr1—O3iv _{2.6541 (13) P1—O3 1.5474 (13)}

Sr1—O3v _{2.6541 (13) P1—O4 1.5985 (13)}

Sr1—O1v _{2.7169 (13) P1—Sr1}viii _{3.2230 (4)}

Sr1—O1iv _{2.7169 (13) P2—O7 1.5105 (13)}

Sr1—P1v _{3.2229 (4) P2—O6 1.5231 (12)}

Sr1—P1iv _{3.2229 (4) P2—O5 1.5247 (13)}

Sr1—O4i _{3.3083 (12) P2—O4 1.5971 (13)}

Sr1—O4 3.3083 (12) O1—Sr1viii _{2.7169 (13)}

Ni1—O6vi _{2.0415 (12) O2—Ni1}iii _{2.0841 (12)}

Ni1—O5vii _{2.0606 (12) O2—Sr1}ix _{2.6234 (13)}

Ni1—O5iii _{2.0704 (12) O3—Ni2}viii _{2.1164 (12)}

Ni1—O2iii _{2.0841 (12) O3—Ni1}viii _{2.1961 (12)}

Ni1—O1 2.0901 (13) O3—Sr1viii _{2.6541 (13)}

Ni1—O3iv _{2.1961 (12) O5—Ni1}x _{2.0606 (12)}

Ni2—O6iv _{2.0458 (12) O5—Ni1}iii _{2.0704 (12)}

Ni2—O6vi _{2.0458 (12) O6—Ni1}xi _{2.0416 (12)}

Ni2—O7i _{2.0552 (12) O6—Ni2}viii _{2.0458 (12)}

Ni2—O7vii _{2.0552 (12) O7—Ni2}x _{2.0552 (12)}

Ni2—O3iv _{2.1163 (12)}

O7—Sr1—O7i _{180.0 O1—Ni1—O3}iv _{97.34 (5)}

O7—Sr1—O2ii _{92.11 (4) O6}vi_{—Ni1—Sr1 75.48 (4)}

O7i_—Sr1—O2ii _{87.89 (4) O5}vii_{—Ni1—Sr1 138.98 (3)}

O7—Sr1—O2iii _{87.89 (4) O5}iii_{—Ni1—Sr1 137.70 (3)}

O7i_—Sr1—O2iii _{92.11 (4) O2}iii_{—Ni1—Sr1 42.18 (3)}

O2ii_—Sr1—O2iii _{180.00 (6) O1—Ni1—Sr1 98.45 (4)}

O7—Sr1—O3iv _{114.02 (4) O3}iv_{—Ni1—Sr1 43.74 (3)}

O7i_—Sr1—O3iv _{65.98 (4) O6}iv_—Ni2—O6vi _180.0

O2ii_—Sr1—O3iv _{112.97 (4) O6}iv_—Ni2—O7i _{94.60 (5)}

O2iii_—Sr1—O3iv _{67.03 (4) O6}vi_—Ni2—O7i _{85.40 (5)}

O7—Sr1—O3v _{65.98 (4) O6}iv_—Ni2—O7vii _{85.40 (5)}

O7i_—Sr1—O3v _{114.02 (4) O6}vi_—Ni2—O7vii _{94.60 (5)}

O2ii_—Sr1—O3v _{67.03 (4) O7}i_—Ni2—O7vii _180.0

O2iii_—Sr1—O3v _{112.97 (4) O6}iv_—Ni2—O3iv _{100.20 (5)}

O3iv_—Sr1—O3v _{180.0 O6}vi_—Ni2—O3iv _{79.80 (5)}

O7—Sr1—O1v _{107.09 (4) O7}i_—Ni2—O3iv _{85.52 (5)}

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Acta Cryst. (2001). E57, i30–i31

O2ii_—Sr1—O1v _{100.84 (4) O6}iv_—Ni2—O3vi _{79.80 (5)}

O2iii_—Sr1—O1v _{79.16 (4) O6}vi_—Ni2—O3vi _{100.20 (5)}

O3iv_—Sr1—O1v _{124.39 (4) O7}i_—Ni2—O3vi _{94.48 (5)}

O3v_—Sr1—O1v _{55.61 (4) O7}vii_—Ni2—O3vi _{85.52 (5)}

O7—Sr1—O1iv _{72.91 (4) O3}iv_—Ni2—O3vi _{180.00 (7)}

O7i_—Sr1—O1iv _{107.09 (4) O6}iv_{—Ni2—Sr1 103.11 (3)}

O2ii_—Sr1—O1iv _{79.16 (4) O6}vi_{—Ni2—Sr1 76.89 (3)}

O2iii_—Sr1—O1iv _{100.84 (4) O7}i_{—Ni2—Sr1 41.10 (3)}

O3iv_—Sr1—O1iv _{55.61 (4) O7}vii_{—Ni2—Sr1 138.90 (3)}

O3v_—Sr1—O1iv _{124.39 (4) O3}iv_{—Ni2—Sr1 44.61 (3)}

O1v_—Sr1—O1iv _{180.0 O3}vi_{—Ni2—Sr1 135.39 (3)}

O7—Sr1—P1v _{83.14 (3) O6}iv_—Ni2—Sr1vii _{76.89 (3)}

O7i_—Sr1—P1v _{96.86 (3) O6}vi_—Ni2—Sr1vii _{103.11 (3)}

O2ii_—Sr1—P1v _{87.62 (3) O7}i_—Ni2—Sr1vii _{138.90 (3)}

O2iii_—Sr1—P1v _{92.38 (3) O7}vii_—Ni2—Sr1vii _{41.10 (3)}

O3iv_—Sr1—P1v _{151.52 (3) O3}iv_—Ni2—Sr1vii _{135.40 (3)}

O3v_—Sr1—P1v _{28.48 (3) O3}vi_—Ni2—Sr1vii _{44.61 (3)}

O1v_—Sr1—P1v _{28.00 (3) Sr1—Ni2—Sr1}vii _180.0

O1iv_—Sr1—P1v _{152.00 (3) O2—P1—O1 117.54 (7)}

O7—Sr1—P1iv _{96.86 (3) O2—P1—O3 111.27 (7)}

O7i_—Sr1—P1iv _{83.14 (3) O1—P1—O3 109.65 (7)}

O2ii_—Sr1—P1iv _{92.38 (3) O2—P1—O4 108.09 (7)}

O2iii_—Sr1—P1iv _{87.62 (3) O1—P1—O4 103.01 (7)}

O3iv_—Sr1—P1iv _{28.48 (3) O3—P1—O4 106.39 (7)}

O3v_—Sr1—P1iv _{151.52 (3) O2—P1—Sr1}viii _{149.48 (5)}

O1v_—Sr1—P1iv _{152.00 (3) O1—P1—Sr1}viii _{57.14 (5)}

O1iv_—Sr1—P1iv _{28.00 (3) O3—P1—Sr1}viii _{54.89 (5)}

P1v_—Sr1—P1iv _{180.0 O4—P1—Sr1}viii _{102.20 (5)}

O7—Sr1—O4i _{132.46 (3) O7—P2—O6 116.65 (7)}

O7i_—Sr1—O4i _{47.54 (3) O7—P2—O5 110.95 (7)}

O2ii_—Sr1—O4i _{51.81 (3) O6—P2—O5 113.68 (7)}

O2iii_—Sr1—O4i _{128.19 (3) O7—P2—O4 104.68 (7)}

O3iv_—Sr1—O4i _{108.93 (3) O6—P2—O4 102.87 (7)}

O3v_—Sr1—O4i _{71.07 (3) O5—P2—O4 106.73 (7)}

O1v_—Sr1—O4i _{60.68 (3) O7—P2—Sr1 37.37 (5)}

O1iv_—Sr1—O4i _{119.32 (3) O6—P2—Sr1 121.93 (5)}

P1v_—Sr1—O4i _{67.61 (2) O5—P2—Sr1 124.07 (5)}

P1iv_—Sr1—O4i _{112.39 (2) O4—P2—Sr1 67.41 (5)}

O7—Sr1—O4 47.54 (3) P1—O1—Ni1 126.85 (7)

O7i_{—Sr1—O4 132.46 (3) P1—O1—Sr1}viii _{94.87 (6)}

O2ii_{—Sr1—O4 128.19 (3) Ni1—O1—Sr1}viii _{126.85 (5)}

O2iii_{—Sr1—O4 51.81 (3) P1—O2—Ni1}iii _{121.48 (7)}

O3iv_{—Sr1—O4 71.07 (3) P1—O2—Sr1}ix _{132.26 (7)}

O3v_{—Sr1—O4 108.93 (3) Ni1}iii_—O2—Sr1ix _{105.58 (5)}

O1v_{—Sr1—O4 119.32 (3) P1—O3—Ni2}viii _{124.43 (7)}

O1iv_{—Sr1—O4 60.68 (3) P1—O3—Ni1}viii _{133.49 (7)}

P1v_{—Sr1—O4 112.39 (2) Ni2}viii_—O3—Ni1viii _{93.50 (5)}

O4i_{—Sr1—O4 180.00 (4) Ni2}viii_—O3—Sr1viii _{101.34 (5)}

O6vi_—Ni1—O5vii _{90.51 (5) Ni1}viii_—O3—Sr1viii _{101.36 (5)}

O6vi_—Ni1—O5iii _{85.70 (5) P2—O4—P1 133.89 (8)}

O5vii_—Ni1—O5iii _{77.30 (5) P2—O4—Sr1 86.12 (5)}

O6vi_—Ni1—O2iii _{84.75 (5) P1—O4—Sr1 138.34 (6)}

O5vii_—Ni1—O2iii _{174.47 (5) P2—O5—Ni1}x _{126.67 (7)}

O5iii_—Ni1—O2iii _{99.46 (5) P2—O5—Ni1}iii _{123.84 (7)}

O6vi_{—Ni1—O1 173.91 (5) Ni1}x_—O5—Ni1iii _{102.70 (5)}

O5vii_{—Ni1—O1 93.94 (5) P2—O6—Ni1}xi _{138.60 (8)}

O5iii_{—Ni1—O1 99.32 (5) P2—O6—Ni2}viii _{120.71 (7)}

O2iii_{—Ni1—O1 91.01 (5) Ni1}xi_—O6—Ni2viii _{100.46 (5)}

O6vi_—Ni1—O3iv _{78.03 (5) P2—O7—Ni2}x _{127.88 (7)}

O5vii_—Ni1—O3iv _{96.04 (5) P2—O7—Sr1 121.52 (7)}

O5iii_—Ni1—O3iv _{162.42 (5) Ni2}x_{—O7—Sr1 106.84 (5)}

O2iii_—Ni1—O3iv _{85.77 (5)}

Symmetry codes: (i) −x+1, −y+2, −z; (ii) x, y+1, z; (iii) −x+1, −y+1, −z; (iv) −x+1, y+1/2, −z+1/2; (v) x, −y+3/2, z−1/2; (vi) x−1, −y+3/2, z−1/2; (vii) x−1,