Filled skutterudite structure of europium ruthenium polyphosphide, EuRu₄P₁₂

The crystal structure of EuRu₄P₁₂ is isotypic with filled skutterudite structures of rare earth transition metal poly­phosphides: RFe₄P₁₂ (R = Ce, Pr, Nd, Sm and Eu), RRu₄P₁₂ (R = La, Ce, Pr and Nd) and ROs₄P₁₂ (R = La, Ce, Pr and Nd). The Ru cation is coordinated by six P anions in a distorted octa­hedral manner. The partially occupied Eu position (site occupancy 0.97) is enclosed by a cage formed by the corner-shared framework of the eight RuP₆ octa­hedra.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](Ru-P) = 0.000 Å
• Disorder in main residue
• R factor = 0.020
• wR factor = 0.024
• Data-to-parameter ratio = 43.5

checkCIF/PLATON results

No syntax errors found



Alert level A
EXPT108_ALERT_1_A  The magnitudes of the crystal dimensions do not
            match the min, mid and max definitions
REFLT03_ALERT_3_A  Reflection count < 85% complete (theta max?)
           From the CIF: _diffrn_reflns_theta_max           74.18
           From the CIF: _reflns_number_total                769
           TEST2: Reflns within _diffrn_reflns_theta_max
           Count of symmetry unique reflns         1007
           Completeness (_total/calc)             76.37%

Author Response: The reflections have not been included for the refinement if the multiple diffraction cannot be avoided. In addition, crystal was cooled to 100 K with an Oxford cryostream cooler installed on a four-circle diffractometer. Since the temperature of sample depends on the \w and \c-angle and the X-ray diffraction measurement was carried out in the equi-temperature area, the \w and \c-angle had the limitation. Thus completeness of the independent reflection was less than 85%. Explained in the refinement section.

Alert level C
PLAT041_ALERT_1_C Calc. and Reported SumFormula    Strings  Differ          ?
PLAT045_ALERT_1_C Calculated and Reported Z Differ by ............       0.50 Ratio
PLAT068_ALERT_1_C Reported F000 Differs from Calcd (or Missing)...          ?
PLAT077_ALERT_4_C Unitcell contains non-integer number of atoms ..          ?

Alert level G
PLAT301_ALERT_3_G Note: Main Residue  Disorder ...................      13.00 Perc.
PLAT808_ALERT_5_G No Parsable SHELXL style Weighting Scheme Found           !
PLAT811_ALERT_5_G No ADDSYM Analysis: Too Many Excluded Atoms ....          !

   2 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   4 ALERT level C = Check and explain
   3 ALERT level G = General alerts; check

   4 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   2 ALERT type 5 Informative message, check


checkCIF publication errors

Alert level G
PUBL013_ALERT_1_G The _publ_section_comment (discussion of study) is
            missing. This is required for a full paper submission (but is
            optional for an electronic paper).

   0 ALERT level A = Data missing that is essential or data in wrong format
   1 ALERT level G = General alerts. Data that may be required is missing

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Related literature

The title compound is isotypic with the Im3 form of LaFe₄P₁₂ (Jeitschko & Braun, 1977). For the single-crystal preparation and magnetic and electrical properties of LaRu₄P₁₂, see: Sekine et al. (2000). For hyperfine interaction in LaRu₄P₁₂, see: Grandjean et al. (1983); Indoh et al. (2002). For extinction correction method, see: Becker & Coppens (1975). For the method used to avoid multiple diffraction, see: Takenaka et al. (2008). [Please check added citations]

S1. Refinement

Multiple diffraction was avoided by using ψ-scans (Takenaka et al., 2008). Intensities were measured at the equi-temperature region of combination of angles ω and χ of a four-circle diffractometer. The intensities have not been included for the refinement if the multiple diffraction cannot be avoided. In addition, the crystal was cooled to 100 K with an Oxford cryostream cooler installed on a four-circle diffractometer. Since the temperature of the sample depends on the ω and χ-angle and the X-ray diffraction measurement was carried out in the equi-temperature area, the ω and χ-angle had the limitation. Thus completeness of the independent reflection was less than 85%.

Structure description

The title compound is isotypic with the Im3 form of LaFe₄P₁₂ (Jeitschko & Braun, 1977). For the single-crystal preparation and magnetic and electrical properties of LaRu₄P₁₂, see: Sekine et al. (2000). For hyperfine interaction in LaRu₄P₁₂, see: Grandjean et al. (1983); Indoh et al. (2002). For extinction correction method, see: Becker & Coppens (1975). For the method used to avoid multiple diffraction, see: Takenaka et al. (2008). [Please check added citations]

Computing details

Data collection: MXCSYS (MacScience, 1995) and IUANGLE (Tanaka et al., 1994); cell refinement: RSLC-3 UNICS system (Sakurai & Kobayashi, 1979); data reduction: RDEDIT (Tanaka, 2008); program(s) used to solve structure: QNTAO (Tanaka et al., 2008); program(s) used to refine structure: QNTAO (Tanaka et al., 2008); molecular graphics: ATOMS for Windows (Dowty, 2000); software used to prepare material for publication: RDEDIT (Tanaka, 2008).

Figures

	Fig. 1. The structure of EuRu4P12 at 100 K. Small yellow and large red spheres, respectively, represent P and Eu atoms. Green distorted octahedron represent RuO6 units.
	Fig. 2. Bonding of Ru4 and P12 around an Eu ion with displacement ellipsoids at the 90% probability level. Red, blue and yellow ellipsoids represent Eu, Ru and P atoms, in Fig. 1.

Europium ruthenium polyphosphide

Crystal data

Eu0.97Ru4P12	Dx = 5.925 Mg m^−3
Mr = 923.37	Mo Kα radiation, λ = 0.71073 Å
Cubic, Im3	Cell parameters from 37 reflections
Hall symbol: -I 2 2 3	θ = 36.0–37.7°
a = 8.04163 (10) Å	µ = 13.37 mm^−1
V = 520.04 (1) Å^3	T = 100 K
Z = 2	Sphere, black
F(000) = 828.4	0.04 mm (radius)

Data collection

MacScience M06XHF22 four-circle diffractometer	769 independent reflections
Radiation source: fine-focus rotating anode	625 reflections with F > 3σ(F)
Graphite monochromator	Rint = 0.016
Detector resolution: 1.25 x 1.25° pixels mm^-1	θmax = 74.2°, θmin = 3.6°
ω/2θ scans	h = −18→20
Absorption correction: for a sphere [transmission coefficients for spheres tabulated in International Tables Vol. C (1992), Table 6.3.3.3, were interpolated with Lagrange's method (four-point interpolation; Yamauchi et al., 1965)]	k = −21→21
Tmin = 0.486, Tmax = 0.526	l = −18→20
1564 measured reflections

Refinement

Refinement on F	Weighting scheme based on measured s.u.'s
Least-squares matrix: full	(Δ/σ)max = 0.018
R[F^2 > 2σ(F^2)] = 0.020	Δρmax = 2.08 e Å^−3
wR(F^2) = 0.024	Δρmin = −1.14 e Å^−3
S = 1.54	Extinction correction: B–C type 1 Gaussian isotropic (Becker & Coppens, 1975)
1304 reflections	Extinction coefficient: 0.068 (6)
30 parameters

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

	x	y	z	Uiso*/Ueq	Occ. (<1)
Eu1	0.000000	0.000000	0.000000	0.00270 (2)	0.970 (4)
Ru1	0.250000	0.250000	0.250000	0.001840 (15)
P1	0.000000	0.359329	0.143386	0.00283 (4)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Eu1	0.00271 (3)	0.00271 (3)	0.00271 (3)	0	0	0
Ru1	0.00185 (3)	0.00185 (3)	0.00185 (3)	0.000108 (17)	0.000108 (17)	0.000108 (17)
P1	0.00268 (10)	0.00301 (10)	0.00285 (10)	0	0	−0.00009 (7)

Geometric parameters (Å, º)

Eu1—P1	3.1112 (3)	Ru1—P1^i	2.3558 (1)
Eu1—Ru1	3.4821 (1)	P1—P1^ii	2.3061 (1)
Ru1—P1	2.3558 (1)	P1—P1^i	3.0829 (1)
Eu1—P1—Ru1	77.78	Ru1—P1—P1^i	49.13
Eu1—P1—P1^ii	68.25	P1—Ru1—P1^i	81.74
Eu1—P1—P1^i	109.77	P1^ii—P1—P1^i	89.59
Ru1—P1—P1^ii	111.34

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