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

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ISSN: 2056-9890

Silver europium(III) polyphosphate

aLaboratoire d'Application de la Chimie aux Ressources et, Substances Naturelles et á l'Environnement, Faculté des Sciences de Bizerte, 7021 Zarzouna Bizerte, Tunisia, bUnité de Recherches de Matériaux de Terres Rares, Centre National de Recherches en Sciences des Matériaux, BP 95 Hammam-Lif 2050, Tunisia, and cLPCML–UMR 5620 CNRS/UCBL, Domaine Scientifique de la Doua, Université Claude Bernard Lyon 1 Batiment Alfred Kastler, 10 rue André-Marie Ampére, 69622 Villeurbanne Cedex, France
*Correspondence e-mail: Mounir.Ayadi@fsm.rnu.tn

(Received 14 December 2008; accepted 3 February 2009; online 11 February 2009)

Europium(III) silver polyphosphate, AgEu(PO3)4, was prepared by the flux method. The atomic arrangement is built up by infinite (PO3)n chains (periodicity of 4) extending along the c axis. These chains are joined to each other by EuO8 dodeca­hedra. The Ag+ cations are located in the voids of this arrangement and are surrounded by five oxygen atoms in a distorted [4+1] coordination.

Related literature

For isotypic AgNd(PO3)4, see: Trunov et al. (1990[Trunov, V. K., Anisimova, N. Yu., Karmanovskaya, N. B. & Chudinova, N. N. (1990). Izv. Akad. Nauk SSSR Neorg. Mater. 26, 1288-1290.]). For related structures, see: Yamada et al. (1974[Yamada, T., Otsuka, K. & Nakano, J. (1974). Appl. Phys. 45, 5096-5097.]); Hashimoto et al. (1991[Hashimoto, N., Takada, Y., Sato, K. & Ibuki, S. (1991). J. Lumin. 48-49, 893-897.]); Horchani et al. (2003[Horchani, K., Gâcon, J. C., Férid, M., Trabelsi-Ayadi, M., Krachni, G. K. & Liu, G. K. (2003). Opt. Mater. 24, 169-174.]); Durif (1995[Durif, A. (1995). In Crystal Chemistry of Condensed Phosphates. New York: Plenium Press.]); Averbuch-Pouchot & Bagieu-Beucher (1987[Averbuch-Pouchot, M. T. & Bagieu-Beucher, M. (1987). Z. Anorg. Allg. Chem. 552, 171-180.]); Férid (2006[Férid, M. (2006). In Etude des propriétés cristallochimiques et physiques des phosphates condensés de terres rares. Paris: Publibook.]).

Experimental

Crystal data
  • AgEu(PO3)4

  • Mr = 575.72

  • Monoclinic, P 21 /n

  • a = 9.9654 (3) Å

  • b = 13.1445 (7) Å

  • c = 7.2321 (3) Å

  • β = 90.42 (1)°

  • V = 947.31 (7) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 9.37 mm−1

  • T = 298 (2) K

  • 0.19 × 0.18 × 0.17 mm

Data collection
  • Nonius KappaCCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.167, Tmax = 0.201

  • 3371 measured reflections

  • 2019 independent reflections

  • 1704 reflections with I > 2σ(I)

  • Rint = 0.042

Refinement
  • R[F2 > 2σ(F2)] = 0.042

  • wR(F2) = 0.109

  • S = 1.03

  • 2019 reflections

  • 164 parameters

  • Δρmax = 2.43 e Å−3

  • Δρmin = −2.06 e Å−3

Data collection: COLLECT (Nonius, 2001[Nonius (2001). COLLECT. Nonius BV, Delf, The Netherlands.]); cell refinement: DENZO/SCALEPACK (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: DENZO/SCALEPACK; 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, 1998[Brandenburg, K. (1998). DIAMOND. University of Bonn, Germany.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

In the last decades, investigation of the synthesis and characterization of rare earth polyphosphates has gained much attention due to their potential applications in diverse areas such as phosphors and laser materials (Yamada et al., 1974; Hashimoto et al., 1991; Horchani et al., 2003). In aim to study the condensed phosphates of rare earth and monovalent cations of general formula MILn(PO3)4 (with MI = monovalent cation)(Durif, 1995), (Ln = Eu, Er, Yb), we have synthesized single crystals of silver europium polyphosphate and investigated its crystalline structure. The atomic arrangement of this structure is characterized by a three-dimensional framework built of (PO3)n chains that are formed by corner-sharing of PO4 tetrahedra. Eu3+ and Ag+ cations alternate in the middle of four such chains with Eu—Ag distances of 3.64 (7) Å (figures 1,3). The EuO8 dodecahedra are isolated from each other and the distances Eu—O are arranged in interval 2.355 (5)- 2.508 (5)Å (figure 2). The polyphosphate chains display two types of distances, P—O terminal ranging from 1.479 (5) to 1.505 (5)Å and P—O bridging, ranging from 1.585 (5)to 1.609 (5)Å. These distances are comparable with those repoted for other condensed phosphates (Durif, 1995; Averbuch-Pouchot & Bagieu Beucher, 1987; Férid (2006). The structural study reported for silver neodymium polyphosphate AgNd(PO3)4 (Trunov et al., 1990) showed that the compound crystallize in the P21/n space group and has similar unit cell prameters compared to AgEu(PO3)4.

Related literature top

For isotypic AgNd(PO3)4, see: Trunov et al. (1990). For related structures, see: Yamada et al. (1974); Hashimoto et al. (1991); Horchani et al. (2003); Durif (1995); Averbuch-Pouchot & Bagieu Beucher (1987); Férid (2006).

Experimental top

Single crystals of AgEu(PO3)4 were prepared by flux method. A mixture of Ag2CO3 (3 g), EuCl3.6H2O (0.5 g) and H3PO4(85%, 17 ml), was progressively heated in a vitreous carbon crucible to 473 K for 12 h. The temperature was then raised and kept at 600 K for 16 days after that, the furnance was slowly cooled until the room temperature. The product was washed with boiling water to separate colorless single crystals from phosphoric acid.

Refinement top

The highest peak and the deepest hole are located 1.22Å and 0.73 Å, respectively, from Ag and Eu.

Computing details top

Data collection: COLLECT (Nonius, 2001); cell refinement: DENZO/SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO/SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS08 (Sheldrick, 2008); program(s) used to refine structure: SHELXL08 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1998); software used to prepare material for publication: SHELXL08 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. : The structural arrangement of AgEu(PO3)4 along a axis.
[Figure 2] Fig. 2. : Projection of EuO8 dodecahedra viewed along [0 0 1] direction.
[Figure 3] Fig. 3. : The sequence of PO4 tetrahedra in AgEu(PO3)4, with displacement ellipsoids drawn at the 50% probability level. [Symmetry codes: (i) 1-x, 2-y, 2-z; (ii) 1-x/2, 2-y, 3-z]
Europium(III) silver polyphosphate top
Crystal data top
AgEu(PO3)4F(000) = 1064
Mr = 575.72Dx = 4.037 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 25 reflections
a = 9.9654 (3) Åθ = 2.4–30.1°
b = 13.1445 (7) ŵ = 9.37 mm1
c = 7.2321 (3) ÅT = 298 K
β = 90.42 (1)°Prism, colorless
V = 947.31 (7) Å30.19 × 0.18 × 0.17 mm
Z = 4
Data collection top
Nonius KappaCCD
diffractometer
2019 independent reflections
Radiation source: fine-focus sealed tube1704 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.042
ϕ and ω scansθmax = 27.5°, θmin = 3.8°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 1212
Tmin = 0.167, Tmax = 0.201k = 1615
3371 measured reflectionsl = 99
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) + (0.0685P)2 + 1.0941P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.109(Δ/σ)max < 0.001
S = 1.03Δρmax = 2.43 e Å3
2019 reflectionsΔρmin = 2.06 e Å3
164 parametersExtinction correction: SHELXL08 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 restraintsExtinction coefficient: 0.00014 (2)
Crystal data top
AgEu(PO3)4V = 947.31 (7) Å3
Mr = 575.72Z = 4
Monoclinic, P21/nMo Kα radiation
a = 9.9654 (3) ŵ = 9.37 mm1
b = 13.1445 (7) ÅT = 298 K
c = 7.2321 (3) Å0.19 × 0.18 × 0.17 mm
β = 90.42 (1)°
Data collection top
Nonius KappaCCD
diffractometer
2019 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
1704 reflections with I > 2σ(I)
Tmin = 0.167, Tmax = 0.201Rint = 0.042
3371 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.042164 parameters
wR(F2) = 0.1090 restraints
S = 1.03Δρmax = 2.43 e Å3
2019 reflectionsΔρmin = 2.06 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*/Ueq
Eu0.52254 (4)0.78212 (2)0.51227 (4)0.01862 (19)
Ag0.43355 (7)0.77670 (5)1.00017 (8)0.0322 (2)
P10.25190 (18)0.90008 (12)1.2536 (2)0.0168 (4)
P20.19511 (18)0.87338 (12)1.6486 (2)0.0167 (4)
P30.79921 (18)0.90983 (12)1.2635 (2)0.0172 (4)
P40.73739 (18)0.88594 (12)0.8738 (2)0.0162 (4)
O10.1995 (5)0.8356 (3)1.1018 (6)0.0241 (11)
O20.3997 (5)0.8951 (4)1.2904 (7)0.0243 (11)
O30.2039 (5)1.0133 (3)1.2168 (7)0.0240 (11)
O40.1629 (5)0.8769 (3)1.4335 (6)0.0198 (10)
O50.3444 (5)0.8678 (4)1.6767 (7)0.0218 (10)
O60.1062 (6)0.7906 (3)1.7231 (6)0.0228 (11)
O70.8644 (5)1.0214 (3)1.2777 (7)0.0193 (10)
O80.9144 (5)0.8395 (3)1.2329 (6)0.0236 (10)
O90.7055 (5)0.8919 (3)1.4217 (6)0.0218 (10)
O100.7085 (5)0.9202 (3)1.0822 (6)0.0203 (10)
O110.8483 (5)0.8097 (3)0.8671 (7)0.0218 (10)
O120.6047 (5)0.8557 (3)0.7933 (6)0.0198 (10)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Eu0.0183 (3)0.0189 (2)0.0186 (2)0.00063 (12)0.00048 (15)0.00108 (12)
Ag0.0262 (4)0.0456 (4)0.0249 (3)0.0034 (2)0.0008 (2)0.0088 (2)
P10.0201 (9)0.0138 (7)0.0165 (7)0.0001 (6)0.0005 (6)0.0001 (6)
P20.0173 (9)0.0155 (8)0.0173 (8)0.0007 (6)0.0001 (6)0.0002 (6)
P30.0206 (9)0.0143 (7)0.0168 (8)0.0004 (6)0.0017 (6)0.0002 (6)
P40.0162 (9)0.0160 (8)0.0165 (8)0.0001 (6)0.0020 (6)0.0012 (6)
O10.034 (3)0.019 (2)0.019 (2)0.004 (2)0.002 (2)0.0060 (19)
O20.023 (3)0.026 (2)0.023 (2)0.000 (2)0.002 (2)0.002 (2)
O30.028 (3)0.016 (2)0.028 (3)0.007 (2)0.004 (2)0.0052 (19)
O40.019 (3)0.025 (2)0.016 (2)0.0000 (19)0.0004 (18)0.0039 (18)
O50.017 (3)0.024 (2)0.025 (2)0.0021 (19)0.003 (2)0.007 (2)
O60.029 (3)0.021 (2)0.018 (2)0.005 (2)0.000 (2)0.0038 (18)
O70.013 (2)0.014 (2)0.031 (3)0.0005 (18)0.0063 (19)0.003 (2)
O80.027 (3)0.018 (2)0.026 (2)0.003 (2)0.001 (2)0.002 (2)
O90.027 (3)0.023 (2)0.016 (2)0.004 (2)0.0040 (19)0.0026 (18)
O100.017 (2)0.020 (2)0.024 (2)0.0009 (19)0.0016 (18)0.0023 (19)
O110.022 (3)0.018 (2)0.025 (2)0.007 (2)0.001 (2)0.002 (2)
O120.023 (3)0.021 (2)0.015 (2)0.005 (2)0.0053 (19)0.0005 (18)
Geometric parameters (Å, º) top
Eu—O11i2.355 (5)P2—O41.587 (5)
Eu—O122.390 (4)P2—O7vi1.598 (5)
Eu—O9ii2.420 (5)P3—O81.492 (5)
Eu—O5ii2.422 (5)P3—O91.500 (5)
Eu—O1iii2.430 (5)P3—O101.593 (5)
Eu—O6iv2.451 (5)P3—O71.607 (5)
Eu—O2ii2.500 (5)P4—O111.493 (5)
Eu—O8i2.508 (5)P4—O121.495 (5)
Eu—Ag3.6453 (7)P4—O3vii1.592 (5)
Eu—Agii3.8025 (7)P4—O101.602 (5)
Ag—O8i2.470 (5)O1—Euviii2.430 (5)
Ag—O122.503 (5)O2—Euv2.500 (5)
Ag—O6iii2.511 (5)O3—P4vii1.592 (5)
Ag—O12.570 (5)O5—Euv2.422 (5)
Ag—Euv3.8025 (7)O6—Euix2.451 (5)
P1—O11.479 (5)O6—Agviii2.511 (5)
P1—O21.496 (6)O7—P2vi1.598 (5)
P1—O31.585 (5)O8—Agx2.470 (5)
P1—O41.609 (5)O8—Eux2.508 (5)
P2—O51.502 (5)O9—Euv2.420 (5)
P2—O61.505 (5)O11—Eux2.355 (5)
O11i—Eu—O12146.43 (17)O12—Ag—Eu40.66 (10)
O11i—Eu—O9ii137.70 (16)O6iii—Ag—Eu117.27 (12)
O12—Eu—O9ii74.62 (16)O1—Ag—Eu119.92 (10)
O11i—Eu—O5ii85.21 (16)O8i—Ag—Euv142.17 (11)
O12—Eu—O5ii69.01 (16)O12—Ag—Euv114.81 (10)
O9ii—Eu—O5ii114.34 (16)O6iii—Ag—Euv39.40 (11)
O11i—Eu—O1iii108.89 (17)O1—Ag—Euv85.49 (10)
O12—Eu—O1iii77.74 (15)Eu—Ag—Euv152.34 (2)
O9ii—Eu—O1iii84.55 (16)O1—P1—O2116.6 (3)
O5ii—Eu—O1iii134.29 (16)O1—P1—O3108.0 (3)
O11i—Eu—O6iv70.99 (18)O2—P1—O3111.5 (3)
O12—Eu—O6iv140.07 (18)O1—P1—O4107.3 (3)
O9ii—Eu—O6iv74.93 (16)O2—P1—O4113.3 (3)
O5ii—Eu—O6iv148.82 (17)O3—P1—O498.4 (3)
O1iii—Eu—O6iv74.24 (16)O5—P2—O6120.1 (3)
O11i—Eu—O2ii70.26 (16)O5—P2—O4109.1 (3)
O12—Eu—O2ii117.94 (15)O6—P2—O4104.9 (3)
O9ii—Eu—O2ii80.70 (17)O5—P2—O7vi111.5 (3)
O5ii—Eu—O2ii71.45 (17)O6—P2—O7vi106.6 (3)
O1iii—Eu—O2ii154.17 (16)O4—P2—O7vi103.2 (3)
O6iv—Eu—O2ii81.49 (16)O8—P3—O9120.0 (3)
O11i—Eu—O8i68.78 (16)O8—P3—O10111.3 (3)
O12—Eu—O8i82.12 (15)O9—P3—O10106.8 (3)
O9ii—Eu—O8i151.72 (16)O8—P3—O7105.3 (3)
O5ii—Eu—O8i70.38 (16)O9—P3—O7110.4 (3)
O1iii—Eu—O8i74.87 (16)O10—P3—O7101.6 (3)
O6iv—Eu—O8i116.40 (15)O11—P4—O12117.5 (3)
O2ii—Eu—O8i125.20 (17)O11—P4—O3vii105.7 (3)
O11i—Eu—Ag103.74 (12)O12—P4—O3vii112.8 (3)
O12—Eu—Ag43.03 (12)O11—P4—O10111.0 (3)
O9ii—Eu—Ag117.57 (11)O12—P4—O10106.1 (3)
O5ii—Eu—Ag49.41 (11)O3vii—P4—O10102.9 (3)
O1iii—Eu—Ag84.88 (11)P1—O1—Euviii144.5 (3)
O6iv—Eu—Ag154.81 (10)P1—O1—Ag93.9 (3)
O2ii—Eu—Ag120.77 (12)Euviii—O1—Ag112.98 (17)
O8i—Eu—Ag42.51 (10)P1—O2—Euv128.1 (3)
O11i—Eu—Agii52.44 (12)P1—O3—P4vii137.7 (4)
O12—Eu—Agii155.75 (11)P2—O4—P1133.6 (3)
O9ii—Eu—Agii85.32 (11)P2—O5—Euv133.2 (3)
O5ii—Eu—Agii108.69 (11)P2—O6—Euix142.4 (3)
O1iii—Eu—Agii114.28 (11)P2—O6—Agviii115.3 (2)
O6iv—Eu—Agii40.55 (12)Euix—O6—Agviii100.06 (18)
O2ii—Eu—Agii43.64 (11)P2vi—O7—P3131.3 (3)
O8i—Eu—Agii120.64 (11)P3—O8—Agx108.8 (3)
Ag—Eu—Agii152.34 (2)P3—O8—Eux145.5 (3)
O8i—Ag—O1280.67 (15)Agx—O8—Eux94.16 (15)
O8i—Ag—O6iii109.46 (15)P3—O9—Euv140.7 (3)
O12—Ag—O6iii93.64 (16)P3—O10—P4130.2 (3)
O8i—Ag—O1110.19 (16)P4—O11—Eux150.8 (3)
O12—Ag—O1132.06 (14)P4—O12—Eu137.3 (3)
O6iii—Ag—O1122.79 (16)P4—O12—Ag118.8 (2)
O8i—Ag—Eu43.33 (11)Eu—O12—Ag96.31 (16)
Symmetry codes: (i) x1/2, y+3/2, z1/2; (ii) x, y, z1; (iii) x+1/2, y+3/2, z1/2; (iv) x+1/2, y+3/2, z3/2; (v) x, y, z+1; (vi) x+1, y+2, z+3; (vii) x+1, y+2, z+2; (viii) x1/2, y+3/2, z+1/2; (ix) x1/2, y+3/2, z+3/2; (x) x+1/2, y+3/2, z+1/2.

Experimental details

Crystal data
Chemical formulaAgEu(PO3)4
Mr575.72
Crystal system, space groupMonoclinic, P21/n
Temperature (K)298
a, b, c (Å)9.9654 (3), 13.1445 (7), 7.2321 (3)
β (°) 90.42 (1)
V3)947.31 (7)
Z4
Radiation typeMo Kα
µ (mm1)9.37
Crystal size (mm)0.19 × 0.18 × 0.17
Data collection
DiffractometerNonius KappaCCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.167, 0.201
No. of measured, independent and
observed [I > 2σ(I)] reflections
3371, 2019, 1704
Rint0.042
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.042, 0.109, 1.03
No. of reflections2019
No. of parameters164
Δρmax, Δρmin (e Å3)2.43, 2.06

Computer programs: COLLECT (Nonius, 2001), DENZO/SCALEPACK (Otwinowski & Minor, 1997), SHELXS08 (Sheldrick, 2008), SHELXL08 (Sheldrick, 2008), DIAMOND (Brandenburg, 1998).

 

Acknowledgements

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

References

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First citationBrandenburg, K. (1998). DIAMOND. University of Bonn, Germany.  Google Scholar
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First citationTrunov, V. K., Anisimova, N. Yu., Karmanovskaya, N. B. & Chudinova, N. N. (1990). Izv. Akad. Nauk SSSR Neorg. Mater. 26, 1288–1290.  CAS Google Scholar
First citationYamada, T., Otsuka, K. & Nakano, J. (1974). Appl. Phys. 45, 5096–5097.  CrossRef CAS Google Scholar

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