inorganic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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KMg0.09Fe1.91(PO4)2

aDepartment of Inorganic Chemistry, Taras Shevchenko National University, 64, Volodymyrska Str., 01601, Kyiv, Ukraine, and bSTC "Institute for Single Crystals", NAS of Ukraine, 60 Lenin Ave., 61001, Kharkiv, Ukraine
*Correspondence e-mail: yats_13@ukr.net

(Received 7 May 2012; accepted 25 May 2012; online 31 May 2012)

KMg0.09Fe1.91(PO4)2, potassium [iron(II)/magnesium] iron(III) bis(orthophosphate), is a solid solution derived from compounds with general formula KMIIFe(PO4)2 (MII = Fe, Cu), in which the Mg atoms substitute Fe atoms only in the octa­hedrally surrounded sites. The framework of the structure is built up from [FeO5] trigonal bipyramids and [MO6] (M = (Fe, Mg) octa­hedra sharing corners and edges and connected by two types of bridging PO4 tetra­hedra. The K+ cations are nine-coordinated and are situated in channels running along [101].

Related literature

For the structure of KFe2(PO4)2, see: Yakubovich et al. (1986[Yakubovich, O. V., Evdokimova, O. A., Mel'nikov, O. K. & Simonov, M. A. (1986). Kristallografiya, 31, 906-912.]) and for the structure of KCuFe(PO4)2, see: Badri et al. (2011[Badri, A., Hidouri, M., Lopez, M. L., Pico, C., Wattiaux, C. & Amara, M. B. (2011). J. Solid State Chem. 184, 937-944.]). For calculations of bond-valence sums, see: Brown & Altermatt (1985[Brown, I. D. & Altermatt, D. (1985). Acta Cryst. B41, 244-247.]).

Experimental

Crystal data
  • KMg0.09Fe1.91(PO4)2

  • Mr = 337.97

  • Monoclinic, P 21 /n

  • a = 7.8444 (3) Å

  • b = 10.0033 (3) Å

  • c = 9.0371 (4) Å

  • β = 114.838 (5)°

  • V = 643.54 (4) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 5.48 mm−1

  • T = 293 K

  • 0.12 × 0.02 × 0.02 mm

Data collection
  • Oxford Diffraction XCalibur-3 CCD diffractometer

  • Absorption correction: multi-scan (Blessing, 1995[Blessing, R. H. (1995). Acta Cryst. A51, 33-38.]) Tmin = 0.857, Tmax = 0.903

  • 10004 measured reflections

  • 2230 independent reflections

  • 2155 reflections with I > 2σ(I)

  • Rint = 0.034

Refinement
  • R[F2 > 2σ(F2)] = 0.042

  • wR(F2) = 0.117

  • S = 1.19

  • 2230 reflections

  • 120 parameters

  • Δρmax = 2.08 e Å−3

  • Δρmin = −1.01 e Å−3

Table 1
Selected bond lengths (Å)

Fe1—O11 1.955 (3)
Fe1—O24 1.984 (3)
Fe1—O24i 1.989 (3)
Fe1—O13 2.041 (3)
Fe1—O12 2.060 (3)
(Fe,Mg)2—O22ii 1.947 (3)
(Fe,Mg)2—O21iii 1.959 (3)
(Fe,Mg)2—O23 1.971 (3)
(Fe,Mg)2—O14 2.003 (3)
(Fe,Mg)2—O13iii 2.072 (3)
(Fe,Mg)2—O12iv 2.133 (3)
Symmetry codes: (i) -x+1, -y, -z-1; (ii) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z-{\script{1\over 2}}]; (iii) -x, -y, -z-1; (iv) [x-{\script{1\over 2}}, -y+{\script{1\over 2}}, z+{\script{1\over 2}}].

Data collection: CrysAlis CCD (Oxford Diffraction, 2006[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]); cell refinement: CrysAlis CCD; data reduction: CrysAlis RED (Oxford Diffraction, 2006[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: DIAMOND (Brandenburg, 1999[Brandenburg, K. (1999). DIAMOND. University of Bonn, Germany.]); software used to prepare material for publication: WinGX publication routines (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and enCIFer (Allen et al., 2004[Allen, F. H., Johnson, O., Shields, G. P., Smith, B. R. & Towler, M. (2004). J. Appl. Cryst. 37, 335-338.])'.

Supporting information


Comment top

KMg0.09Fe1.91(PO4)2 is a solid solution and crystallizes in the KFe2(PO4)2 structure type (originally reported in space group P21/a; Yakubovich et al., 1986). KCuFe(PO4)2 (originally reported in space group P21/n; Badri et al., 2011) is another isotypic member.

The asymmetric unit of KMg0.09Fe1.91(PO4)2 consist of one K, two Fe (one is partially occupied by Mg), two P and eight oxygen positions (Fig. 1). The main building block involves two [(M)O6] octahedra (M = Fe2,Mg) and two [Fe1O5] trigonal bipyramids connected by four orthophosphate tetrahedra. Such blocks are aggregated into a three-dimensional framework which can be described by the general formula [Mg0.09Fe1.91(PO4)2]- (Fig. 2). It should be noted, that Mg was determined only in the six-coordinated position while the five-coordinated position is occupied only by Fe.

The M sites lie in a rather distorted octahedron which vertices are shared by two types of orthophosphate tetrahedra (the Fe2—O distances varies from 1.947 (3) to 2.133 (3) Å). Completeness of the Fe1 environment is achieved by three orthophosphate tetrahedra connected to the metal atom only by one vertex and one orthophosphate tetrahedron connected via an edge (the Fe1—O distances lie in the range 1.955 (3) to 2.060 (3) Å). In comparison with KCuFe(PO4)2 (Badri et al., 2011), the bond lengths of Fe2—O are very close in both structures. In KCuFe(PO4)2 this position is occupied by Fe3+, whereas in the structure of KMg0.09Fe1.91(PO4)2 it is occupied by both Mg and Fe. The average Fe—O lengths of both positions are very close (Fe1—Oaverage = 2,00 Å; Fe2—Oaverage = 2,01 Å). Thus it can be assumed that Fe2+ and Fe3+ are distributed over both positions which is confirmed by bond valence sums (BVS) calculations (Brown & Altermatt, 1985). For both positions the BVS values were found inbetween those expected for full occupancy with Fe2+ and Fe3+. Fe1: 2.6 valence units (v.u.) with the parameters of Fe3+ and 2.4 v.u. with the parameters of Fe2+; Fe2: 3.0 v.u. with the parameters of Fe3+ and 2.5 v.u. with the parameters of Fe2+.

The geometry of the orthophosphate tetrahedra is close to regular with P—O bond length ranging from 1.513 (3) to 1.567 (3) Å. The BVS values for both P atoms are close to the expected 5 (4.91 v.u. for P1; 4.95 v.u. for P2).

The potassium atoms are located in hexagonal channels running along [101] (Fig. 3). The distorted [KO9] coordination polyhedron is formed by nine phosphate O atoms assuming a cut-off distance of 3.2 Å.

Related literature top

For the structure of KFe2(PO4)2, see: Yakubovich et al. (1986) and for the structure of KCuFe(PO4)2, see: Badri et al. (2011). For calculations of bond-valence sums, see: Brown & Altermatt (1985).

Experimental top

The title compound was obtained from high-temperature solution in the pseudo-system K2O—P2O5—MoO3—Fe2O3—MgO. The calculated amounts of KPO3 (3.54 g), H3PO4 (0.98 g), Fe2O3 (0.96 g), MgO (0.48 g) and K2Mo2O7 (1.136 g) in molar ratios of K/P/Fe/Mg/Mo equal to 1:1.1:0.3:0.3:0.15 was mixed, ground in an agate mortar and heated up to 1273 K in a platinum crucible. Then the temperature was cooled down to 873 K during 8 h (at a constant rate) to crystallize the desired crystals. The flux was poured out of the crucible and the obtained crystals were recovered from the remaining solidified flux using hot water.

Refinement top

The atomic positions and labelling of atoms are the same as in Badri et al. (2011) to simplify any comparison.

In the first steps of structure refinement, the Mg atoms were placed into the same positions as Fe. The coordinates and the ADPs of both Mg1 and Fe1, Mg2 and Fe2 sites were constrained to be equal. The corresponding occupancies were freely refined but constrained to unity. It was found that the Mg occupancy in the M1 position is negative. Thus the occupancy of Fe in this site was set to 1. The Mg quantity was refined only in the position M2. At the same time, we refined the occupancy of K1 site freely; it was found to be 1.

The remaining highest positive electron density was found at a distance of 0.69 Å from Fe1 and the highest negative density at 0.44 Å from P1.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis CCD (Oxford Diffraction, 2006); data reduction: CrysAlis RED (Oxford Diffraction, 2006); 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: WinGX publication routines (Farrugia, 1999) and enCIFer (Allen et al., 2004)'.

Figures top
[Figure 1] Fig. 1. The asymmetric unit of KMg0.09Fe1.91(PO4)2, showing displacement ellipsoids at the 50% probability level.
[Figure 2] Fig. 2. Elementary fragments in the titled compound.
[Figure 3] Fig. 3. A projection of the structure of KMg0.09Fe1.91(PO4)2 along [101].
Potassium [iron(II)/magnesium] iron(III) bis(orthophosphate) top
Crystal data top
KMg0.09Fe1.91(PO4)2F(000) = 654.4
Mr = 337.97Dx = 3.488 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 10004 reflections
a = 7.8444 (3) Åθ = 2.9–32°
b = 10.0033 (3) ŵ = 5.48 mm1
c = 9.0371 (4) ÅT = 293 K
β = 114.838 (5)°Needle, light pink
V = 643.54 (4) Å30.12 × 0.02 × 0.02 mm
Z = 4
Data collection top
Oxford Diffraction XCalibur-3 CCD
diffractometer
2230 independent reflections
Radiation source: fine-focus sealed tube2155 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.034
ϕ and ω scansθmax = 32°, θmin = 2.9°
Absorption correction: multi-scan
(Blessing, 1995)
h = 1011
Tmin = 0.857, Tmax = 0.903k = 1414
10004 measured reflectionsl = 1313
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.042 w = 1/[σ2(Fo2) + (0.0371P)2 + 6.6825P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.117(Δ/σ)max < 0.001
S = 1.19Δρmax = 2.08 e Å3
2230 reflectionsΔρmin = 1.01 e Å3
120 parametersExtinction correction: SHELXL
0 restraintsExtinction coefficient: 0.0145 (14)
Crystal data top
KMg0.09Fe1.91(PO4)2V = 643.54 (4) Å3
Mr = 337.97Z = 4
Monoclinic, P21/nMo Kα radiation
a = 7.8444 (3) ŵ = 5.48 mm1
b = 10.0033 (3) ÅT = 293 K
c = 9.0371 (4) Å0.12 × 0.02 × 0.02 mm
β = 114.838 (5)°
Data collection top
Oxford Diffraction XCalibur-3 CCD
diffractometer
2230 independent reflections
Absorption correction: multi-scan
(Blessing, 1995)
2155 reflections with I > 2σ(I)
Tmin = 0.857, Tmax = 0.903Rint = 0.034
10004 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.042120 parameters
wR(F2) = 0.1170 restraints
S = 1.19Δρmax = 2.08 e Å3
2230 reflectionsΔρmin = 1.01 e Å3
Special details top

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 (Å2) top
xyzUiso*/UeqOcc. (<1)
K10.42060 (18)0.13394 (13)0.07587 (14)0.0267 (3)
Fe10.37733 (7)0.11765 (5)0.55702 (6)0.00590 (15)
Fe20.01350 (8)0.12386 (5)0.25744 (7)0.0065 (2)0.912 (8)
Mg20.01350 (8)0.12386 (5)0.25744 (7)0.0065 (2)0.088 (8)
P10.12822 (14)0.16101 (10)0.86090 (12)0.0088 (2)
P20.26703 (14)0.09247 (10)0.35182 (12)0.0085 (2)
O110.4483 (4)0.2619 (3)0.3964 (4)0.0127 (5)
O120.2987 (4)0.2495 (3)0.7494 (4)0.0112 (5)
O130.1465 (4)0.0404 (3)0.7444 (4)0.0120 (5)
O140.1437 (5)0.1137 (3)0.0138 (4)0.0138 (6)
O210.0945 (4)0.1311 (3)0.5040 (4)0.0133 (5)
O220.3516 (4)0.2128 (3)0.2422 (4)0.0126 (5)
O230.2247 (4)0.0124 (3)0.2489 (4)0.0125 (5)
O240.4195 (4)0.0311 (3)0.4003 (4)0.0131 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
K10.0313 (6)0.0285 (6)0.0181 (5)0.0129 (4)0.0080 (4)0.0006 (4)
Fe10.0070 (2)0.0052 (2)0.0045 (2)0.00011 (16)0.00150 (18)0.00047 (16)
Fe20.0080 (3)0.0057 (3)0.0054 (3)0.00005 (17)0.0023 (2)0.00025 (17)
Mg20.0080 (3)0.0057 (3)0.0054 (3)0.00005 (17)0.0023 (2)0.00025 (17)
P10.0103 (4)0.0086 (4)0.0068 (4)0.0005 (3)0.0030 (3)0.0000 (3)
P20.0100 (4)0.0082 (4)0.0074 (4)0.0006 (3)0.0036 (3)0.0001 (3)
O110.0136 (12)0.0126 (13)0.0120 (12)0.0031 (10)0.0054 (10)0.0031 (10)
O120.0127 (12)0.0110 (12)0.0077 (11)0.0028 (10)0.0020 (10)0.0005 (9)
O130.0128 (12)0.0104 (12)0.0095 (12)0.0022 (10)0.0015 (10)0.0019 (10)
O140.0176 (14)0.0159 (14)0.0076 (12)0.0002 (11)0.0050 (11)0.0024 (10)
O210.0151 (13)0.0150 (13)0.0073 (12)0.0000 (10)0.0024 (10)0.0011 (10)
O220.0157 (13)0.0117 (13)0.0113 (12)0.0041 (10)0.0066 (11)0.0026 (10)
O230.0134 (12)0.0120 (13)0.0114 (12)0.0022 (10)0.0045 (10)0.0022 (10)
O240.0134 (12)0.0123 (13)0.0164 (13)0.0033 (10)0.0089 (11)0.0049 (11)
Geometric parameters (Å, º) top
K1—O222.806 (3)Fe2—O22v1.947 (3)
K1—O23i2.830 (3)Fe2—O21vi1.959 (3)
K1—O11ii2.854 (3)Fe2—O231.971 (3)
K1—O11i2.930 (3)Fe2—O142.003 (3)
K1—O21iii2.955 (3)Fe2—O13vi2.072 (3)
K1—O12ii3.007 (3)Fe2—O12vii2.133 (3)
K1—O233.054 (3)P1—O14viii1.513 (3)
K1—O24i3.131 (3)P1—O11ix1.520 (3)
K1—O143.167 (3)P1—O121.567 (3)
Fe1—O111.955 (3)P1—O131.567 (3)
Fe1—O241.984 (3)P2—O211.520 (3)
Fe1—O24iv1.989 (3)P2—O221.523 (3)
Fe1—O132.041 (3)P2—O231.528 (3)
Fe1—O122.060 (3)P2—O241.562 (3)
O22—K1—O23i114.12 (10)O23—Fe2—O13vi93.03 (13)
O22—K1—O11ii66.54 (9)O14—Fe2—O13vi88.97 (12)
O23i—K1—O11ii175.96 (10)O22v—Fe2—O12vii86.54 (12)
O22—K1—O11i136.60 (10)O21vi—Fe2—O12vii91.89 (12)
O23i—K1—O11i77.66 (9)O23—Fe2—O12vii175.72 (12)
O11ii—K1—O11i104.68 (8)O14—Fe2—O12vii92.19 (12)
O22—K1—O21iii55.69 (9)O13vi—Fe2—O12vii88.90 (12)
O23i—K1—O21iii91.67 (9)O14viii—P1—O11ix112.93 (18)
O11ii—K1—O21iii91.87 (9)O14viii—P1—O12112.93 (17)
O11i—K1—O21iii83.54 (9)O11ix—P1—O12108.38 (18)
O22—K1—O12ii121.25 (9)O14viii—P1—O13110.67 (18)
O23i—K1—O12ii121.56 (9)O11ix—P1—O13110.31 (17)
O11ii—K1—O12ii59.29 (8)O12—P1—O13100.98 (16)
O11i—K1—O12ii49.85 (8)O21—P2—O22111.52 (18)
O21iii—K1—O12ii104.06 (9)O21—P2—O23112.74 (18)
O22—K1—O2349.28 (9)O22—P2—O23107.06 (17)
O23i—K1—O23107.82 (8)O21—P2—O24110.00 (18)
O11ii—K1—O2369.39 (9)O22—P2—O24108.52 (17)
O11i—K1—O23170.19 (9)O23—P2—O24106.79 (18)
O21iii—K1—O23104.12 (9)P1x—O11—Fe1118.74 (18)
O12ii—K1—O23121.31 (9)P1x—O11—K1v124.41 (17)
O22—K1—O24i159.49 (9)Fe1—O11—K1v86.74 (11)
O23i—K1—O24i48.85 (8)P1x—O11—K1i95.94 (14)
O11ii—K1—O24i129.51 (9)Fe1—O11—K1i106.47 (13)
O11i—K1—O24i57.90 (9)K1v—O11—K1i124.91 (11)
O21iii—K1—O24i127.13 (9)P1—O12—Fe193.03 (14)
O12ii—K1—O24i78.93 (8)P1—O12—Fe2xi141.86 (18)
O23—K1—O24i119.28 (9)Fe1—O12—Fe2xi116.63 (14)
O22—K1—O1498.12 (9)P1—O12—K1v91.93 (13)
O23i—K1—O14102.39 (9)Fe1—O12—K1v80.92 (10)
O11ii—K1—O1473.59 (9)Fe2xi—O12—K1v114.88 (12)
O11i—K1—O14120.87 (9)P1—O13—Fe193.73 (14)
O21iii—K1—O14153.74 (9)P1—O13—Fe2vi136.95 (18)
O12ii—K1—O1487.46 (9)Fe1—O13—Fe2vi128.51 (15)
O23—K1—O1450.59 (8)P1xii—O14—Fe2142.0 (2)
O24i—K1—O1477.83 (8)P1xii—O14—K1108.69 (16)
O11—Fe1—O2496.53 (13)Fe2—O14—K1107.41 (12)
O11—Fe1—O24iv117.65 (13)P2—O21—K1xiii107.95 (16)
O24—Fe1—O24iv84.56 (13)Fe2vi—O21—K1xiii105.53 (13)
O11—Fe1—O13140.54 (13)P2—O22—Fe2ii138.67 (19)
O24—Fe1—O1397.59 (13)P2—O22—K1106.73 (15)
O24iv—Fe1—O13100.27 (13)Fe2ii—O22—K1111.49 (13)
O11—Fe1—O1292.56 (13)P2—O23—Fe2139.32 (19)
O24—Fe1—O12169.72 (13)P2—O23—K1i102.50 (14)
O24iv—Fe1—O1295.47 (12)Fe2—O23—K1i113.17 (13)
O13—Fe1—O1272.26 (12)P2—O23—K196.07 (14)
O22v—Fe2—O21vi87.21 (13)Fe2—O23—K1112.59 (13)
O22v—Fe2—O2391.51 (13)K1i—O23—K172.18 (8)
O21vi—Fe2—O2391.82 (13)P2—O24—Fe1125.27 (18)
O22v—Fe2—O1491.01 (13)P2—O24—Fe1iv130.84 (19)
O21vi—Fe2—O14175.44 (13)Fe1—O24—Fe1iv95.44 (13)
O23—Fe2—O1484.03 (13)P2—O24—K1i89.85 (13)
O22v—Fe2—O13vi175.43 (13)Fe1—O24—K1i98.85 (12)
O21vi—Fe2—O13vi93.14 (13)Fe1iv—O24—K1i111.87 (13)
Symmetry codes: (i) x+1, y, z; (ii) x+1/2, y1/2, z1/2; (iii) x+1/2, y1/2, z+1/2; (iv) x+1, y, z1; (v) x+1/2, y+1/2, z1/2; (vi) x, y, z1; (vii) x1/2, y+1/2, z+1/2; (viii) x, y, z1; (ix) x1/2, y+1/2, z1/2; (x) x+1/2, y+1/2, z+1/2; (xi) x+1/2, y+1/2, z1/2; (xii) x, y, z+1; (xiii) x1/2, y1/2, z1/2.

Experimental details

Crystal data
Chemical formulaKMg0.09Fe1.91(PO4)2
Mr337.97
Crystal system, space groupMonoclinic, P21/n
Temperature (K)293
a, b, c (Å)7.8444 (3), 10.0033 (3), 9.0371 (4)
β (°) 114.838 (5)
V3)643.54 (4)
Z4
Radiation typeMo Kα
µ (mm1)5.48
Crystal size (mm)0.12 × 0.02 × 0.02
Data collection
DiffractometerOxford Diffraction XCalibur-3 CCD
diffractometer
Absorption correctionMulti-scan
(Blessing, 1995)
Tmin, Tmax0.857, 0.903
No. of measured, independent and
observed [I > 2σ(I)] reflections
10004, 2230, 2155
Rint0.034
(sin θ/λ)max1)0.746
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.042, 0.117, 1.19
No. of reflections2230
No. of parameters120
Δρmax, Δρmin (e Å3)2.08, 1.01

Computer programs: CrysAlis CCD (Oxford Diffraction, 2006), CrysAlis RED (Oxford Diffraction, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 1999), WinGX publication routines (Farrugia, 1999) and enCIFer (Allen et al., 2004)'.

Selected bond lengths (Å) top
Fe1—O111.955 (3)Fe2—O21iii1.959 (3)
Fe1—O241.984 (3)Fe2—O231.971 (3)
Fe1—O24i1.989 (3)Fe2—O142.003 (3)
Fe1—O132.041 (3)Fe2—O13iii2.072 (3)
Fe1—O122.060 (3)Fe2—O12iv2.133 (3)
Fe2—O22ii1.947 (3)
Symmetry codes: (i) x+1, y, z1; (ii) x+1/2, y+1/2, z1/2; (iii) x, y, z1; (iv) x1/2, y+1/2, z+1/2.
 

References

First citationAllen, F. H., Johnson, O., Shields, G. P., Smith, B. R. & Towler, M. (2004). J. Appl. Cryst. 37, 335–338.  Web of Science CrossRef CAS IUCr Journals Google Scholar
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