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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 64| Part 6| June 2008| Page i33
doi:10.1107/S1600536808013032

Lutetium ultraphosphate

Karima Horchani-Naifera and Mokhtar Férida*

aUnité de Recherches de Matériaux de Terres Rares, Centre National de Recherches en Sciences des Matériaux, BP 95 Hammam-Lif, 2050, Tunisia
*Correspondence e-mail: mokhtar.ferid@inrst.rnrt.tn

(Received 1 April 2008; accepted 2 May 2008; online 10 May 2008)

The structure of the title compound, LuP5O14, comprises puckered eight-membered PO4 rings linked by the lutetium cations in a complex way, forming a three-dimensional framework. Each eight-membered phosphate ring shares a bridging tetra­hedron with each of four adjacent tetra­hedra, to form layers of PO4 tetra­hedra. These layers are c/2 in thickness and parallel to the ab plane. Each Lu ion is contained in one such layer, forming bonds to six O atoms in that layer and also to one O atom belonging to a tetra­hedron in each of the layers lying above and below it. The LuO8 polyhedra are isolated from one another, since they share no common atoms. The Lu ions lie on twofold axes (special position 4e) and the shortest Lu⋯Lu distance is 5.703 (1) Å.

Related literature

For related literature, see: Durif (1971[Durif, A. (1971). Bull. Soc. Fr. Mineral. Cristallogr. 94, 314-318.]); Hong (1974[Hong, H. Y.-P. (1974). Acta Cryst. B30, 468-474.]); Hong & Pierce (1974[Hong, H. Y.-P. & Pierce, J. W. (1974). Mater. Res. Bull. 9, 179-190.]). For the classification of ultraphosphates, see: Bagieu-Beucher & Tranqui (1970[Bagieu-Beucher, M. & Tranqui, D. (1970). Bull. Soc. Fr. Mineral. Cristallogr. 93, 505-508.]).

Experimental

Crystal data

  • LuP5O14

  • Mr = 553.82

  • Monoclinic, C 2/c

  • a = 12.8128 (14) Å

  • b = 12.6821 (13) Å

  • c = 12.3330 (13) Å

  • β = 91.295 (3)°

  • V = 2003.5 (4) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 10.74 mm−1

  • T = 298 (2) K

  • 0.20 × 0.19 × 0.18 mm
Data collection

  • Enraf–Nonius CAD-4 diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.121, Tmax = 0.145

  • 10422 measured reflections

  • 2912 independent reflections

  • 2734 reflections with I > 2σ(I)

  • Rint = 0.031

  • 2 standard reflections every 150 reflections intensity decay: 2%
Refinement

  • R[F2 > 2σ(F2)] = 0.019

  • wR(F2) = 0.050

  • S = 1.08

  • 2912 reflections

  • 183 parameters

  • Δρmax = 1.34 e Å−3

  • Δρmin = −0.98 e Å−3

Data collection: CAD-4 EXPRESS (Duisenberg, 1992[Duisenberg, A. J. M. (1992). J. Appl. Cryst. 25, 92-96.]; Enraf–Nonius, 1994[Enraf-Nonius (1994). CAD-4 EXPRESS. Enraf-Nonius, Delft, The Netherlands.]; Macíček & Yordanov, 1992[Macíček, J. & Yordanov, A. (1992). J. Appl. Cryst. 25, 73-80.]); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995[Harms, K. & Wocadlo, S. (1995). XCAD4. University of Marburg, Germany.]); 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, 2001[Brandenburg, K. (2001). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808013032/br2072sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808013032/br2072Isup2.hkl

checkCIF report


Comment top

The structure of LuP5O14 is a type (II) rare-earth ultraphosphates as classified by Bagieu-Beucher & Tranqui (1970), since it crystallizes in the monoclinic system with space group C2/c. In this structure, the lutetium ion is surrounded by eight oxygen atoms that form distorted polyhedra. Each of the oxygen atoms in the LuO8 polyhedra are shared exclusively with PO4 tetrahedra to form a three-dimensional framework, which delimits interesting tunnels (Fig.1). The structure is built up from (PO4) tetrahedra (Fig.2) which are cross-linked by bridging O atoms, but these do not form helical ribbons, as in the NdP5O14 structure type (I) (Hong, 1974), and HoP5O14 structure type (III) (Durif, 1971). The anion is being constructed from a succession of eight-membred rings interconnected through the ternary tetrahedra in a complex way (Fig.3a). The members of an individual ring are shown with yellow color. Each ring shares a bridging tetrahedron with each of four adjacent tetrahedra to form layers of PO4 tetrahedra, as illustrated in Fig.3b. These layers are about c/2 in thickness and parallel to the a-b plane. Each Lu ion is contained in one such layer, forming bonds to six oxygen in that layer and also to one oxygen belonging to a tetrahedron in each of the layers lying above and bolow it. the LuO8 polyhedra are isolated from one another, since they share no common atoms. The shortest Lu-Lu distances are 5.703. The LuP5O14 ultraphosphate is isostructural with YbP5O14 (Hong & Pierce, 1974).

Related literature top

For related literature, see: Durif (1971); Hong (1974); Hong & Pierce (1974). For the classification of ultraphosphates, see: Bagieu-Beucher & Tranqui (1970).

Experimental top

Single crystal of LuP5O14 was prepared by flux method. At room temperature, 0.5 g of Lu2O3 were slowly added to 10 ml of phosphoric acid H3PO4 (85%). The mixture was then slowly heated to 673 K and kept at this temperature for seven days. colorless, crystals were separated from the excess phosphoric acid by washing the product in boiling water.

Refinement top

The highest peak and the deepest hole are located 0.79Å and 0.54 Å, respectively, from Lu1 and Lu2.

Computing details top

Data collection: CAD-4 EXPRESS (Duisenberg, 1992; Enraf–Nonius, 1994; Macíček & Yordanov, 1992); cell refinement: CAD-4 EXPRESS (Duisenberg, 1992; Enraf–Nonius, 1994; Macíček & Yordanov, 1992)'; data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2001); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The structural arrangement of LuP5O14 along the a axis, showing tunnels in which the Lu ions are located.
[Figure 2] Fig. 2. Projection of the ultraphosphate with anisotropic displacement parameters drawn at the 50% probability level. [Symmetry codes: (i) x, y+1, z ; (ii)-x+5/2, y+1/2, -z+3/2 ; (iii) x+1/2, y+1/2, z; (iv)x, -y+2, z-1/2 ; (v)x-1/2, -y+3/2, z-1/2.
[Figure 3] Fig. 3. a) Projection of one layer showing LuO8 polyhedra and linkage of PO4 tetrahedra forming rings (yellow) in LuP5O14. b) Projection of one layer along the b axis with c/2 thickness.
lutetium ultraphosphate top
Crystal data top
LuP5O14F(000) = 2064
Mr = 553.82Dx = 3.672 Mg m−3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 7043 reflections
a = 12.8128 (14) Åθ = 2.3–30.0°
b = 12.6821 (13) ŵ = 10.74 mm−1
c = 12.3330 (13) ÅT = 298 K
β = 91.295 (3)°Prism, colorless
V = 2003.5 (4) Å30.20 × 0.19 × 0.18 mm
Z = 8
Data collection top
Enraf–Nonius CAD-4
diffractometer		2734 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.031
Graphite monochromatorθmax = 30.0°, θmin = 2.3°
ω/2θ scansh = −17→18
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		k = −17→17
Tmin = 0.121, Tmax = 0.145l = −17→17
10422 measured reflections2 standard reflections every 150 reflections
2912 independent reflections intensity decay: 2%
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)] = 0.019 w = 1/[σ2(Fo2) + (0.028P)2 + 3.0307P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.050(Δ/σ)max = 0.003
S = 1.08Δρmax = 1.34 e Å−3
2912 reflectionsΔρmin = −0.98 e Å−3
183 parametersExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 restraintsExtinction coefficient: 0.00637 (11)
Crystal data top
LuP5O14V = 2003.5 (4) Å3
Mr = 553.82Z = 8
Monoclinic, C2/cMo Kα radiation
a = 12.8128 (14) ŵ = 10.74 mm−1
b = 12.6821 (13) ÅT = 298 K
c = 12.3330 (13) Å0.20 × 0.19 × 0.18 mm
β = 91.295 (3)°
Data collection top
Enraf–Nonius CAD-4
diffractometer		2734 reflections with I > 2σ(I)
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		Rint = 0.031
Tmin = 0.121, Tmax = 0.1452 standard reflections every 150 reflections
10422 measured reflections intensity decay: 2%
2912 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.019183 parameters
wR(F2) = 0.0500 restraints
S = 1.08Δρmax = 1.34 e Å−3
2912 reflectionsΔρmin = −0.98 e Å−3
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*/Ueq
Lu11.00001.019590 (11)0.75000.00946 (6)
Lu21.00000.469251 (11)0.75000.00947 (6)
P11.18263 (5)0.63687 (5)0.89095 (5)0.01020 (13)
P20.97504 (5)0.65029 (5)0.96672 (5)0.01037 (13)
P30.85012 (5)0.83192 (5)0.89783 (5)0.01042 (13)
P40.85469 (5)0.96507 (5)0.50182 (6)0.01080 (14)
P51.17542 (6)1.24856 (5)0.76032 (6)0.01017 (14)
O11.15332 (15)0.54741 (15)0.82204 (16)0.0131 (4)
O21.24259 (17)0.72754 (16)0.83475 (17)0.0131 (4)
O31.09081 (14)0.69824 (15)0.94396 (15)0.0120 (3)
O41.24970 (13)0.60463 (17)0.99342 (13)0.0121 (4)
O50.97503 (15)0.59905 (15)1.07328 (15)0.0137 (4)
O60.93961 (15)0.59620 (15)0.86627 (15)0.0132 (4)
O70.91291 (17)0.75979 (14)0.97911 (18)0.0114 (4)
O80.90954 (15)0.87184 (15)0.80717 (15)0.0132 (4)
O90.75333 (18)0.76371 (15)0.86473 (18)0.0128 (4)
O100.80606 (15)0.91824 (14)0.97493 (15)0.0123 (4)
O110.88893 (16)0.96091 (15)0.61582 (16)0.0139 (4)
O120.92416 (15)1.06579 (15)0.91286 (15)0.0135 (4)
O131.12590 (16)0.34943 (15)0.73083 (16)0.0142 (4)
O141.11367 (16)1.15411 (15)0.78473 (16)0.0147 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Lu10.00912 (9)0.00934 (9)0.00992 (9)0.000−0.00025 (6)0.000
Lu20.00918 (9)0.00909 (8)0.01011 (9)0.000−0.00038 (6)0.000
P10.0100 (3)0.0094 (3)0.0112 (3)0.0001 (2)−0.0002 (2)0.0002 (2)
P20.0100 (3)0.0099 (3)0.0112 (3)0.0004 (2)0.0001 (2)0.0002 (2)
P30.0103 (3)0.0097 (3)0.0112 (3)−0.0001 (2)−0.0002 (2)0.0000 (2)
P40.0108 (3)0.0097 (3)0.0119 (3)−0.0006 (2)−0.0003 (2)0.0001 (2)
P50.0094 (3)0.0099 (3)0.0112 (3)−0.0002 (2)−0.0004 (3)−0.0006 (2)
O10.0125 (9)0.0125 (8)0.0143 (9)−0.0011 (7)0.0008 (7)−0.0012 (7)
O20.0142 (10)0.0108 (8)0.0144 (9)−0.0013 (7)0.0030 (7)0.0002 (7)
O30.0099 (8)0.0113 (8)0.0149 (9)0.0002 (7)0.0013 (7)−0.0004 (7)
O40.0115 (10)0.0129 (9)0.0118 (9)0.0024 (6)−0.0014 (7)−0.0003 (6)
O50.0148 (9)0.0127 (8)0.0135 (9)0.0004 (7)−0.0001 (7)0.0015 (7)
O60.0132 (9)0.0135 (8)0.0129 (9)0.0018 (7)−0.0009 (7)−0.0010 (7)
O70.0107 (10)0.0119 (8)0.0116 (9)0.0017 (6)−0.0008 (7)−0.0007 (6)
O80.0153 (9)0.0122 (8)0.0122 (8)−0.0023 (7)0.0012 (7)−0.0001 (7)
O90.0119 (10)0.0136 (8)0.0129 (10)−0.0016 (7)−0.0012 (8)0.0000 (7)
O100.0123 (9)0.0098 (8)0.0150 (9)0.0007 (7)0.0013 (7)−0.0012 (7)
O110.0150 (10)0.0142 (8)0.0125 (9)−0.0020 (7)−0.0014 (7)0.0002 (7)
O120.0143 (9)0.0129 (8)0.0135 (9)−0.0007 (7)0.0013 (7)0.0002 (7)
O130.0148 (9)0.0137 (8)0.0142 (9)0.0028 (7)−0.0001 (7)0.0002 (7)
O140.0156 (9)0.0131 (8)0.0151 (9)−0.0044 (7)−0.0009 (7)0.0002 (7)
Geometric parameters (Å, º) top
Lu1—O142.2775 (19)P2—O71.6097 (19)
Lu1—O14i2.2775 (19)P2—O31.633 (2)
Lu1—O112.283 (2)P3—O81.458 (2)
Lu1—O11i2.283 (2)P3—O91.559 (2)
Lu1—O82.3213 (19)P3—O101.5638 (19)
Lu1—O8i2.3213 (19)P3—O71.566 (2)
Lu1—O122.3260 (19)P4—O111.464 (2)
Lu1—O12i2.3260 (19)P4—O12iv1.481 (2)
Lu2—O13i2.2326 (19)P4—O4v1.6111 (19)
Lu2—O132.2326 (19)P4—O10iv1.637 (2)
Lu2—O62.3016 (19)P5—O13vi1.470 (2)
Lu2—O6i2.3016 (19)P5—O141.470 (2)
Lu2—O12.356 (2)P5—O2vii1.614 (2)
Lu2—O1i2.356 (2)P5—O9viii1.623 (2)
Lu2—O5ii2.3604 (19)O2—P5ix1.614 (2)
Lu2—O5iii2.3604 (19)O4—P4x1.6111 (19)
P1—O11.462 (2)O5—Lu2iii2.3604 (19)
P1—O21.555 (2)O9—P5xi1.623 (2)
P1—O31.5659 (19)O10—P4xii1.637 (2)
P1—O41.5665 (18)O12—P4xii1.481 (2)
P2—O51.466 (2)O13—P5xiii1.470 (2)
P2—O61.479 (2)
O14—Lu1—O14i82.98 (10)O13—Lu2—O5iii76.40 (7)
O14—Lu1—O11140.00 (7)O6—Lu2—O5iii73.85 (7)
O14i—Lu1—O1173.88 (7)O6i—Lu2—O5iii142.33 (7)
O14—Lu1—O11i73.88 (7)O1—Lu2—O5iii73.25 (7)
O14i—Lu1—O11i140.00 (7)O1i—Lu2—O5iii126.65 (7)
O11—Lu1—O11i141.95 (10)O5ii—Lu2—O5iii136.94 (9)
O14—Lu1—O8150.35 (7)O1—P1—O2115.98 (12)
O14i—Lu1—O8109.89 (7)O1—P1—O3116.30 (11)
O11—Lu1—O869.49 (7)O2—P1—O3101.66 (11)
O11i—Lu1—O879.86 (7)O1—P1—O4113.30 (12)
O14—Lu1—O8i109.89 (7)O2—P1—O4106.56 (12)
O14i—Lu1—O8i150.35 (7)O3—P1—O4101.33 (10)
O11—Lu1—O8i79.86 (7)O5—P2—O6122.63 (12)
O11i—Lu1—O8i69.49 (7)O5—P2—O7106.70 (11)
O8—Lu1—O8i72.36 (10)O6—P2—O7109.67 (11)
O14—Lu1—O1285.80 (7)O5—P2—O3109.73 (11)
O14i—Lu1—O1272.29 (7)O6—P2—O3106.95 (11)
O11—Lu1—O12116.25 (7)O7—P2—O398.52 (11)
O11i—Lu1—O1273.85 (7)O8—P3—O9114.72 (12)
O8—Lu1—O1273.73 (7)O8—P3—O10115.17 (11)
O8i—Lu1—O12133.38 (7)O9—P3—O10104.58 (12)
O14—Lu1—O12i72.29 (7)O8—P3—O7115.10 (12)
O14i—Lu1—O12i85.80 (7)O9—P3—O7103.75 (11)
O11—Lu1—O12i73.85 (7)O10—P3—O7101.94 (11)
O11i—Lu1—O12i116.25 (7)O11—P4—O12iv121.99 (12)
O8—Lu1—O12i133.38 (7)O11—P4—O4v105.88 (11)
O8i—Lu1—O12i73.73 (7)O12iv—P4—O4v108.80 (11)
O12—Lu1—O12i150.82 (9)O11—P4—O10iv109.37 (11)
O13i—Lu2—O1394.22 (10)O12iv—P4—O10iv108.74 (11)
O13i—Lu2—O698.99 (7)O4v—P4—O10iv99.76 (11)
O13—Lu2—O6142.75 (7)O13vi—P5—O14121.90 (13)
O13i—Lu2—O6i142.75 (7)O13vi—P5—O2vii104.38 (11)
O13—Lu2—O6i98.99 (7)O14—P5—O2vii112.10 (11)
O6—Lu2—O6i91.22 (10)O13vi—P5—O9viii110.34 (11)
O13i—Lu2—O1147.63 (7)O14—P5—O9viii104.96 (11)
O13—Lu2—O174.22 (7)O2vii—P5—O9viii101.37 (12)
O6—Lu2—O176.11 (7)P1—O1—Lu2138.32 (12)
O6i—Lu2—O169.60 (7)P1—O2—P5ix141.48 (14)
O13i—Lu2—O1i74.22 (7)P1—O3—P2125.49 (12)
O13—Lu2—O1i147.63 (7)P1—O4—P4x129.58 (12)
O6—Lu2—O1i69.60 (7)P2—O5—Lu2iii170.97 (13)
O6i—Lu2—O1i76.11 (7)P2—O6—Lu2138.19 (12)
O1—Lu2—O1i130.25 (10)P3—O7—P2133.72 (14)
O13i—Lu2—O5ii76.40 (7)P3—O8—Lu1141.86 (12)
O13—Lu2—O5ii74.67 (7)P3—O9—P5xi138.16 (14)
O6—Lu2—O5ii142.33 (7)P3—O10—P4xii127.96 (13)
O6i—Lu2—O5ii73.85 (7)P4—O11—Lu1148.50 (12)
O1—Lu2—O5ii126.65 (7)P4xii—O12—Lu1147.46 (12)
O1i—Lu2—O5ii73.25 (7)P5xiii—O13—Lu2151.04 (13)
O13i—Lu2—O5iii74.67 (7)P5—O14—Lu1156.41 (13)
Symmetry codes: (i) −x+2, y, −z+3/2; (ii) x, −y+1, z−1/2; (iii) −x+2, −y+1, −z+2; (iv) x, −y+2, z−1/2; (v) x−1/2, −y+3/2, z−1/2; (vi) x, y+1, z; (vii) −x+5/2, y+1/2, −z+3/2; (viii) x+1/2, y+1/2, z; (ix) −x+5/2, y−1/2, −z+3/2; (x) x+1/2, −y+3/2, z+1/2; (xi) x−1/2, y−1/2, z; (xii) x, −y+2, z+1/2; (xiii) x, y−1, z.

Experimental details

Crystal data
Chemical formulaLuP5O14
Mr553.82
Crystal system, space groupMonoclinic, C2/c
Temperature (K)298
a, b, c (Å)12.8128 (14), 12.6821 (13), 12.3330 (13)
β (°) 91.295 (3)
V (Å3)2003.5 (4)
Z8
Radiation typeMo Kα
µ (mm−1)10.74
Crystal size (mm)0.20 × 0.19 × 0.18
Data collection
DiffractometerEnraf–Nonius CAD-4
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.121, 0.145
No. of measured, independent and
observed [I > 2σ(I)] reflections		10422, 2912, 2734
Rint0.031
(sin θ/λ)max (Å−1)0.703
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.019, 0.050, 1.08
No. of reflections2912
No. of parameters183
Δρmax, Δρmin (e Å−3)1.34, −0.98

Computer programs: , CAD-4 EXPRESS (Duisenberg, 1992; Enraf–Nonius, 1994; Macíček & Yordanov, 1992)', XCAD4 (Harms & Wocadlo, 1995), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 2001).

 

Acknowledgements

This work was supported by the Ministry of Higher Education, Scientific Research and Technology of Tunisia.

References

First citationBagieu-Beucher, M. & Tranqui, D. (1970). Bull. Soc. Fr. Mineral. Cristallogr. 93, 505–508.  CAS Google Scholar
 First citationBrandenburg, K. (2001). DIAMOND. Crystal Impact GbR, Bonn, Germany.  Google Scholar
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ISSN: 2056-9890
Volume 64| Part 6| June 2008| Page i33
doi:10.1107/S1600536808013032
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