PMCCPMCCPMCC

Search tips
Search criteria 

Advanced

 
Logo of actaeInternational Union of Crystallographysearchopen accessarticle submissionjournal home pagethis article
 
Acta Crystallogr Sect E Struct Rep Online. 2009 November 1; 65(Pt 11): i73.
Published online 2009 October 3. doi:  10.1107/S1600536809038100
PMCID: PMC2971448

Tripraseodymium penta­iron(III) dodeca­oxide, Pr3Fe5O12: a synchrotron radiation study

Abstract

The title compound, penta­iron tripraseodymium dodeca­oxide (PrIG), has an iron garnet structure. There are two Fe site symmetries. One of the Fe atoms is coordinated by six O atoms, forming a slightly distorted octa­hedron, and has An external file that holds a picture, illustration, etc.
Object name is e-65-00i73-efi1.jpg site symmetry. The other Fe atom is coordinated by four O atoms, forming a slightly distorted tetra­hedron, and has An external file that holds a picture, illustration, etc.
Object name is e-65-00i73-efi2.jpg site symmetry. FeO6 octa­hedra and FeO4 tetra­hedra are linked together by corners. The Pr atom is coordinated by eight O atoms, forming a distorted dodeca­hedron, and has 222 site symmetry. The O atoms occupy the general positions.

Related literature

The title compound is isotypic with the Ia An external file that holds a picture, illustration, etc.
Object name is e-65-00i73-efi1.jpg d form of Y3Fe5O12 (YIG). For related structures, see: Bonnet et al. (1975 [triangle]). For details of the crystal growth from low-temperature liquid-phase epitaxy, see: Fratello et al. (1986 [triangle]). For the extinction correction, see: Becker & Coppens (1975 [triangle]). X-ray intensities were measured avoiding multiple diffraction, see: Takenaka et al. (2008 [triangle]).

Experimental

Crystal data

  • Pr3Fe5O12
  • M r = 893.98
  • Cubic, An external file that holds a picture, illustration, etc.
Object name is e-65-00i73-efi4.jpg
  • a = 12.6302 (3) Å
  • V = 2014.79 (8) Å3
  • Z = 8
  • Synchrotron radiation
  • λ = 0.67171 Å
  • μ = 17.41 mm−1
  • T = 298 K
  • 0.035 mm (radius)

Data collection

  • Rigaku AFC four-circle diffractometer
  • Absorption correction: for a sphere [transmission coefficients for spheres tabulated in International Tables C (1992), Table 6.3.3.3, were interpolated with Lagrange’s method (four-point interpolation; Yamauchi et al., 1965 [triangle])] T min = 0.413, T max = 0.441
  • 9351 measured reflections
  • 1728 independent reflections
  • 1728 reflections with F > 3σ(F)
  • R int = 0.016

Refinement

  • R[F 2 > 2σ(F 2)] = 0.019
  • wR(F 2) = 0.021
  • S = 1.06
  • 9351 reflections
  • 17 parameters
  • Δρmax = 2.52 e Å−3
  • Δρmin = −3.16 e Å−3

Data collection: AFC-5, specially designed for PF-BL14A (Rigaku, 1984 [triangle]) and IUANGLE (Tanaka et al., 1994 [triangle]); cell refinement: RSLC-3 UNICS system (Sakurai & Kobayashi, 1979 [triangle]); data reduction: RDEDIT (Tanaka, 2008 [triangle]); program(s) used to solve structure: QNTAO (Tanaka et al., 2008 [triangle]); program(s) used to refine structure: QNTAO; molecular graphics: ATOMS for Windows (Dowty, 2000 [triangle]); software used to prepare material for publication: RDEDIT.

Table 1
Selected geometric parameters (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809038100/br2121sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809038100/br2121Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors thank Dr V. J. Fratello for supplying the crystals.

supplementary crystallographic information

Comment

The title compound, Pr3Fe5O12 (PrIG), was difficult to be grown. It was grown by the low-temperature-liquid-phase epitaxy for the first time by Fratello et al. (1986). Though the crystal structure was assumed as iron-garnet-type structure by lattice constant and extinction rule, the complete structure was not determined. In this paper, we determine the O atom position and the complete structure by the full matrix least-squares program QNTAO. Since the R-factor is small and the residual density has no significant peaks where no atoms exists, the structure was finally determined to be iron-garnet structure. It is isotypic with the Ia3d form of Y3Fe5O12 (YIG). (Bonnet et al., 1975). The Pr atom is coordinated by eight oxygen atoms. It forms a distorted dodecahedron. There are two Fe site symmetries. One of the Fe atom is coordinated by six oxygen atoms. It forms a slitely distorted octahedron. The other Fe atom is coordinated by four oxygen atoms. It forms a slightly distorted tetrahedron. FeO6 octahedron and FeO4 tetrahedron are linked together by corners. The structure of PrIG is drawn in Fig.1. And displacement ellipsoids of PrO8 is drawn in Fig.2.

Experimental

Single crystals of praseodymium iron garnet were prepared by low temperature liquid phase epitaxy on Sm3(ScGa)5O12 seeds with lattice parameters near the projected values for PrIG.

Refinement

X-ray intensities were measured avoiding multiple diffraction. (Takenaka et al., 2008).

Figures

Fig. 1.
The structure of Pr3Fe5O12. Small red and large green spheres represent O and Pr atoms, respectively. Purple octahedron and blue tetrahedron represent FeO6 and FeO4 units, respectively.
Fig. 2.
View of PrO8 with displacement ellipsoids at the 90% probability level. Green and red ellipsoids represent Pr and O atoms, in Fig.1.

Crystal data

Pr3Fe5O12Dx = 5.894 Mg m3
Mr = 893.98Synchrotron radiation, λ = 0.67171 Å
Cubic, Ia3dCell parameters from 9 reflections
Hall symbol: -I 4bd 2c 3θ = 17.5–52.3°
a = 12.6302 (3) ŵ = 17.41 mm1
V = 2014.79 (8) Å3T = 298 K
Z = 8Sphere, black
F(000) = 32240.04 mm (radius)

Data collection

Rigaku AFC four-circle diffractometer1728 independent reflections
Si 1111728 reflections with F > 3σ(F)
Detector resolution: 1.25 × 1.25° pixels mm-1Rint = 0.016
ω/2θ scansθmax = 68.3°, θmin = 3.7°
Absorption correction: for a sphere [Transmission coefficients for spheres tabulated in International Tables C (1992), Table 6.3.3.3, were interpolated with Lagrange's method (four-point interpolation (Yamauchi et al., 1965)]h = −9→34
Tmin = 0.413, Tmax = 0.441k = −9→32
9351 measured reflectionsl = −9→34

Refinement

Refinement on FPrimary atom site location: isomorphous structure methods
Least-squares matrix: fullWeighting scheme based on measured s.u.'s
R[F2 > 2σ(F2)] = 0.019(Δ/σ)max = 0.003
wR(F2) = 0.021Δρmax = 2.52 e Å3
S = 1.06Δρmin = −3.16 e Å3
9351 reflectionsExtinction correction: B–C type 1 Gaussian isotropic (Becker & Coppens, 1975)
17 parametersExtinction coefficient: 0.255 (5)

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

xyzUiso*/Ueq
Pr10.1250000.0000000.2500000.00531 (1)
Fe10.0000000.0000000.0000000.00512 (1)
Fe20.3750000.0000000.2500000.00533 (1)
O1−0.029622 (2)0.052553 (2)0.149166 (2)0.00711 (5)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Pr10.00406 (2)0.00594 (2)0.00594 (2)000.00111 (1)
Fe10.00512 (2)0.00512 (2)0.00512 (2)−0.00023 (1)−0.00023 (1)−0.00023 (1)
Fe20.00411 (3)0.00594 (2)0.00594 (2)000
O10.00718 (8)0.00829 (8)0.00587 (7)−0.00004 (6)0.00080 (6)0.00038 (6)

Geometric parameters (Å, °)

Pr1—O12.42410 (10)Fe1—O1i2.03220 (10)
Pr1—O1i2.54010 (10)Fe1—O1viii2.03220 (10)
Pr1—O1ii2.42410 (10)Fe1—O1ix2.03220 (10)
Pr1—O1iii2.54010 (10)Fe1—O1x2.03220 (10)
Pr1—O1iv2.42410 (10)Fe1—O1xi2.03220 (10)
Pr1—O1v2.54010 (10)Fe2—O1xii1.87450 (10)
Pr1—O1vi2.42410 (10)Fe2—O1iv1.87450 (10)
Pr1—O1vii2.54010 (10)Fe2—O1xiii1.87450 (10)
Fe1—O12.03220 (10)Fe2—O1vi1.87450 (10)
O1—Pr1—O1i67.75 (1)O1—Fe1—O1viii85.87 (1)
O1—Pr1—O1ii72.66 (1)O1—Fe1—O1ix180.00
O1—Pr1—O1iii124.91 (1)O1—Fe1—O1x94.13 (1)
O1—Pr1—O1iv111.18 (1)O1—Fe1—O1xi94.13 (1)
O1—Pr1—O1v73.25 (1)O1xii—Fe2—O1vi114.39 (1)
O1—Pr1—O1vi159.51 (1)O1xii—Fe2—O1iv114.39 (1)
O1—Pr1—O1vii95.43 (1)O1xii—Fe2—O1xiii100.02 (1)
O1—Fe1—O1i85.87 (1)

Symmetry codes: (i) z, x, y; (ii) x, −y, −z+1/2; (iii) z, −x, −y+1/2; (iv) −x+1/4, −z+1/4, −y+1/4; (v) −z+1/4, −y+1/4, −x+1/4; (vi) −x+1/4, z−1/4, y+1/4; (vii) −z+1/4, y−1/4, x+1/4; (viii) y, z, x; (ix) −x, −y, −z; (x) −z, −x, −y; (xi) −y, −z, −x; (xii) x+1/2, y, −z+1/2; (xiii) x+1/2, −y, z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BR2121).

References

  • Becker, P. J. & Coppens, P. (1975). Acta Cryst. A31, 417–425.
  • Bonnet, M., Delapalme, A., Fuess, H. & Thomas, M. (1975). Acta Cryst. B31, 2233–2240.
  • Dowty, E. (2000). ATOMS for Windows Shape Software, Kingsport, Tennessee, USA.
  • Fratello, V. J., Brandle, C. D., Slusky, S. E. G., Valentino, A. J., Norelli, M. P. & Wolfe, R. (1986). Cryst. Growth, 75, 281–283.
  • Rigaku (1984). AFC-5 Rigaku Corporation, Tokyo, Japan.
  • Sakurai, T. & Kobayashi, K. (1979). Rep. Inst. Phys. Chem. Res.55, 69–77.
  • Takenaka, Y., Sakakura, T., Tanaka, K. & Kishimoto, S. (2008). Acta Cryst. A64, C566.
  • Tanaka, K. (2008). RDEDIT Unpublished.
  • Tanaka, K., Kumazawa, S., Tsubokawa, M., Maruno, S. & Shirotani, I. (1994). Acta Cryst. A50, 246–252.
  • Tanaka, K., Makita, R., Funahashi, S., Komori, T. & Zaw Win, (2008). Acta Cryst. A64, 437–449. [PubMed]
  • Yamauchi, J., Moriguchi, S. & Ichimatsu, S. (1965). Numerical Calculation Method for Computer Tokyo: Baifūkan.

Articles from Acta Crystallographica Section E: Structure Reports Online are provided here courtesy of International Union of Crystallography