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Acta Crystallogr Sect E Struct Rep Online. 2010 April 1; 66(Pt 4): i28–i29.
Published online 2010 March 24. doi:  10.1107/S1600536810010093
PMCID: PMC2983799

Sodium terbium(III) polyphosphate

Abstract

Single crystals of the title compound, NaTb(PO3)4, were obtained by solid-state reaction. This compound belongs to type II of long-chain polyphosphates with the general formula A I B III(PO3)4. It is isotypic with the NaNd(PO3)4 and NaEr(PO3)4 homologues. The crystal structure is built up of infinite crenelated chains of corner-sharing PO4 tetra­hedra with a repeating unit of four tetra­hedra. These chains, extending parallel to [100], are linked by isolated TbO8 square anti­prisms, forming a three-dimensional framework. The Na+ ions are located in channels running along [010] and are surrounded by six oxygen atoms in a distorted octa­hedral environment within a cut-off distance <2.9 Å.

Related literature

All NaLn(PO3)4 polyphosphates reported up to now, where Ln is a trivalent rare earth element, belong to type II of long-chain polyphosphates A I B III(PO3)4. For corresponding isotypic crystal structures, see: El Masloumi et al. (2005 [triangle]) and Zhu et al. (2006 [triangle]) for Ln = La; Zhu et al. (2008 [triangle]) for Ce and Eu; Horchani-Naifer et al. (2009 [triangle]) for Pr; Koizumi et al. (1976 [triangle]) for Nd; Amami et al. (2005 [triangle]) for Gd; El Masloumi et al. (2008 [triangle]) for Y; Amami et al. (2004 [triangle]) for Ho; Maksimova et al. (1988 [triangle]) for Er. For other isotypic polyphosphates with general composition A I B III(PO3)4, see: Linde et al. (1983 [triangle]) for AB = KCe; Naïli et al. (2006 [triangle]) for AgGd; Belam et al. (2007 [triangle]) and Jaoudi et al. (2003 [triangle]); for NaBi. For a review on the crystal chemistry of polyphos­phates, see: Durif (1995 [triangle]).

Experimental

Crystal data

  • NaTb(PO3)4
  • M r = 497.79
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-00i28-efi1.jpg
  • a = 7.1712 (1) Å
  • b = 13.0512 (2) Å
  • c = 9.7547 (1) Å
  • β = 90.604 (1)°
  • V = 912.92 (2) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 8.56 mm−1
  • T = 296 K
  • 0.41 × 0.12 × 0.10 mm

Data collection

  • Bruker APEXII CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2008 [triangle]) T min = 0.127, T max = 0.478
  • 26640 measured reflections
  • 6971 independent reflections
  • 6445 reflections with I > 2σ(I)
  • R int = 0.025

Refinement

  • R[F 2 > 2σ(F 2)] = 0.022
  • wR(F 2) = 0.055
  • S = 1.10
  • 6971 reflections
  • 163 parameters
  • Δρmax = 2.12 e Å−3
  • Δρmin = −2.03 e Å−3

Data collection: APEX2 (Bruker, 2008 [triangle]); cell refinement: SAINT (Bruker, 2008 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: DIAMOND (Brandenburg, 1999 [triangle]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008 [triangle]).

Table 1
Selected bond lengths (Å)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810010093/wm2313sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810010093/wm2313Isup2.hkl

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

supplementary crystallographic information

Comment

It is now well established that long-chain polyphosphates with general formula AIBIII(PO3)4 can be divided in seven structural types (Jaoudi et al., 2003). All long-chain polyphosphates of formula NaLnP4O12 (Ln = rare earth element) reported up to now ( El Masloumi et al. 2005; Zhu et al. 2006; Zhu et al. 2008; Horchani-Naifer et al. 2009; Koizumi et al. 1976; Amami et al. 2005; El Masloumi et al. 2008; Amami et al. 2004; Maksimova et al. 1988) belong to the structural type II which has been first described on basis of the KCe(PO3)4 structure (Linde et al., 1983). A few other AIBIII cationic combinations such as AgGd (Naïli et al. 2006) and NaBi (Jaoudi et al. 2003; Belam et al. 2007) also lead to polyphosphates which belong to the structural type II. The structure of the title compound also fits in this isotypic series. The underlying structure has many times been described as built up of (PO3) chains running along the [100] direction and further linked by isolated LnO8 polyhedra. The resulting three dimensional framework delimits tunnels where the Na+ ions are located. Instead of using this description, we will focus on the connectivity between the (PO3) chains and the TbO8 square antiprisms for our account. Each TbO8 square antiprism is linked to four (PO3) chains by corner-sharing involving the non-bridging oxygen atoms of the PO4 groups that exhibit the shorter P—O distances within the chain. Their P—O distances range from 1.4792 (13) Å to 1.4918 (13) Å. The chains are crenelated with a repeating unit of four corner-sharing tetrahedra, as displayed in Fig. 1. The repeating unit is built up of PO4 tetrahedra corresponding to the four crystallographically independent phosphorus atoms labelled from P1 to P4. If the origin of the chain is taken at the O2 position for instance, then the P2 and P4 tetrahedra are the end-groupings of the repeating unit while P1 and P3 tetrahedra are involved in the internal diphosphate group. Each (PO3) chain is linked to four rows of isolated TbO8 square antiprisms parallel to the direction of the chain (Fig. 2). With the aforementioned origin convention both terminal P(2)O4 and P(4)O4 tetrahedra are connected in a bidentate fashion on one side of the square face of the archimedean antiprisms of the first row while the internal P(1)O4—P(3)O4 diphosphate group is also connected in a bidentate fashion on one side of the square face of the antiprisms of the second row (Fig. 3a and 3 b). Therefore the two rows of TbO8 polyhedra are translated with a half-period of the (PO3) chain relative to one another (Fig. 3c). Thus the tetrahedra involved in the internal P2O7 groups share their non-bridging oxygen atoms with two TbO8 polyhedra belonging to each of the first and second rows, respectively. Then the (PO3) chain is connected to the third and fourth rows in a similar way but the role played by the couples P(1)O4—P(3)O4 and P(2)O4—P(4)O4 are inverted, this last becoming the internal diphosphate group.

For a general review on the crystal chemistry of polyphosphates, see: Durif (1995).

Experimental

Crystals of the title compound were synthesized by reacting Tb4O7 with (NH4)H2PO4 and Na2CO3 in a platinum crucible. A mixture of these reagents in the molar ratio 5 : 85 : 10 was used for the synthesis. The mixture has first been heated at 473 K for 12 h, then at 573 K for 12 h and finally at 773 K for 24 h. The muffle furnace was then cooled down first to 723 K at the rate of 2 K.h-1 and then to room temperature at the rate of 15 K.h-1. Single crystals were extracted from the batch by washing with hot water.

Refinement

The highest residual peak in the final difference Fourier map was located 0.61 Å from atom Tb and the deepest hole was located 0.45 Å from atom Tb.

Figures

Fig. 1.
ORTEP view of the repeating unit of the (PO3)∞ chains. Displacement ellipsoids are drawn at the 50% probability level. Symmetry codes: (i) -x+1, -y, -z+2; (ii) x+1/2, -y+1/2, z-1/2; (iii) x+1/2, -y+1/2, z+1/2; (iv) -x+2, -y, -z+2; (v) x+1, y, ...
Fig. 2.
View of four rows of TbO8 polyhedra connected through one (PO3)∞ chain.
Fig. 3.
Details of the connections between the (PO3)∞ chains and the TbO8 polyhedra: a) view showing the two kind of bidentate attachments. b) view showing the bidentate attachments and the PO4 groups shared between two TbO8 square antiprisms belonging ...

Crystal data

NaTb(PO3)4F(000) = 928
Mr = 497.79Dx = 3.622 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 27177 reflections
a = 7.1712 (1) Åθ = 3.5–43.9°
b = 13.0512 (2) ŵ = 8.56 mm1
c = 9.7547 (1) ÅT = 296 K
β = 90.604 (1)°Needle, colourless
V = 912.92 (2) Å30.41 × 0.12 × 0.10 mm
Z = 4

Data collection

Bruker APEXII CCD diffractometer6971 independent reflections
Radiation source: fine-focus sealed tube6445 reflections with I > 2σ(I)
graphiteRint = 0.025
Detector resolution: 8.3333 pixels mm-1θmax = 43.8°, θmin = 3.5°
ω and [var phi] scansh = −13→8
Absorption correction: multi-scan (SADABS; Bruker, 2008)k = −25→17
Tmin = 0.127, Tmax = 0.478l = −19→18
26640 measured reflections

Refinement

Refinement on F20 constraints
Least-squares matrix: fullPrimary atom site location: structure-invariant direct methods
R[F2 > 2σ(F2)] = 0.022Secondary atom site location: difference Fourier map
wR(F2) = 0.055w = 1/[σ2(Fo2) + (0.0212P)2 + 1.888P] where P = (Fo2 + 2Fc2)/3
S = 1.10(Δ/σ)max = 0.003
6971 reflectionsΔρmax = 2.12 e Å3
163 parametersΔρmin = −2.03 e Å3
0 restraints

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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)

xyzUiso*/Ueq
Na−0.00068 (15)0.22179 (9)1.06373 (11)0.02105 (19)
Tb0.512736 (10)0.219027 (5)0.976594 (7)0.00611 (2)
P10.24948 (6)0.10137 (3)1.24460 (4)0.00585 (6)
P20.87630 (6)0.11488 (3)0.76336 (4)0.00525 (5)
P30.64720 (6)0.12784 (3)1.30443 (4)0.00514 (5)
P41.26813 (6)0.09081 (3)0.69983 (4)0.00584 (6)
O10.22211 (18)0.28938 (9)0.89407 (14)0.01015 (19)
O21.08668 (17)0.08115 (10)0.79214 (13)0.00956 (18)
O30.36683 (19)0.31058 (10)1.14928 (13)0.01003 (18)
O40.79883 (18)0.14688 (10)0.89738 (13)0.00974 (18)
O50.42970 (17)0.12511 (10)1.33504 (13)0.00876 (17)
O60.09345 (18)0.16584 (10)1.29625 (14)0.01081 (19)
O71.28234 (19)−0.02144 (9)0.63492 (13)0.01000 (19)
O80.7833 (2)0.01335 (10)0.70784 (14)0.01089 (19)
O90.73740 (19)0.33790 (10)1.08306 (14)0.01139 (19)
O100.28652 (19)0.10837 (10)1.09492 (13)0.01001 (18)
O110.67772 (19)0.13293 (10)1.15449 (13)0.01040 (19)
O120.42899 (18)0.11069 (11)0.79349 (15)0.0125 (2)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Na0.0165 (4)0.0309 (5)0.0157 (4)0.0077 (3)−0.0022 (3)0.0012 (3)
Tb0.00563 (3)0.00740 (3)0.00529 (3)0.00035 (2)0.00018 (2)−0.00028 (2)
P10.00480 (13)0.00573 (13)0.00703 (14)−0.00036 (10)0.00008 (10)−0.00060 (11)
P20.00561 (13)0.00468 (12)0.00548 (13)0.00011 (10)0.00126 (10)0.00071 (10)
P30.00532 (13)0.00475 (12)0.00534 (13)−0.00013 (10)−0.00051 (10)−0.00029 (10)
P40.00542 (13)0.00510 (13)0.00700 (14)0.00056 (10)0.00050 (10)0.00007 (11)
O10.0087 (4)0.0083 (4)0.0134 (5)0.0018 (3)−0.0021 (4)0.0039 (4)
O20.0055 (4)0.0131 (5)0.0101 (4)0.0020 (3)0.0015 (3)0.0033 (4)
O30.0113 (5)0.0089 (4)0.0100 (4)−0.0008 (4)0.0020 (3)−0.0047 (4)
O40.0090 (4)0.0131 (5)0.0071 (4)0.0025 (4)0.0029 (3)−0.0016 (4)
O50.0052 (4)0.0133 (5)0.0077 (4)−0.0013 (3)−0.0003 (3)−0.0016 (4)
O60.0076 (4)0.0113 (5)0.0135 (5)0.0027 (4)0.0004 (3)−0.0030 (4)
O70.0151 (5)0.0058 (4)0.0090 (4)0.0031 (4)−0.0026 (4)−0.0009 (3)
O80.0137 (5)0.0067 (4)0.0123 (5)−0.0031 (4)−0.0005 (4)−0.0007 (4)
O90.0130 (5)0.0094 (4)0.0118 (5)−0.0029 (4)0.0043 (4)−0.0046 (4)
O100.0121 (5)0.0105 (4)0.0074 (4)−0.0018 (4)−0.0006 (3)−0.0001 (3)
O110.0106 (5)0.0140 (5)0.0066 (4)0.0017 (4)0.0009 (3)0.0027 (4)
O120.0070 (4)0.0156 (5)0.0149 (5)−0.0001 (4)−0.0020 (4)−0.0064 (4)

Geometric parameters (Å, °)

Na—O4i2.3680 (17)P2—O41.4858 (13)
Na—O9i2.4223 (17)P2—O81.5768 (13)
Na—O62.4700 (17)P2—O21.5937 (13)
Na—O12.4750 (18)P2—Navi3.3550 (12)
Na—O102.5520 (17)P3—O111.4827 (13)
Na—O11i2.7369 (18)P3—O1vii1.4868 (13)
Na—P12.9554 (11)P3—O7viii1.5897 (13)
Na—O32.9897 (17)P3—O51.5915 (13)
Na—P4ii3.2464 (11)P3—Navii3.3808 (12)
Na—P2i3.3550 (12)P4—O9iv1.4853 (13)
Na—P3iii3.3808 (12)P4—O12vi1.4867 (13)
Tb—O32.3232 (12)P4—O21.5952 (13)
Tb—O122.3511 (13)P4—O71.5997 (13)
Tb—O112.3729 (12)P4—Naix3.2464 (12)
Tb—O6iv2.3894 (13)O1—P3iii1.4868 (12)
Tb—O42.3930 (12)O3—P2x1.4792 (13)
Tb—O12.4082 (12)O4—Navi2.3680 (17)
Tb—O92.4589 (13)O6—Tbx2.3894 (13)
Tb—O102.4676 (13)O7—P3viii1.5897 (13)
P1—O101.4896 (14)O8—P1v1.5857 (13)
P1—O61.4918 (13)O9—P4x1.4853 (13)
P1—O8v1.5857 (13)O9—Navi2.4223 (17)
P1—O51.5876 (12)O11—Navi2.7369 (18)
P2—O3iv1.4792 (13)O12—P4i1.4867 (13)
O4i—Na—O9i81.14 (5)O1—Tb—O1078.97 (4)
O4i—Na—O6131.70 (7)O9—Tb—O10127.07 (4)
O9i—Na—O6108.55 (6)O3—Tb—Navi105.53 (4)
O4i—Na—O194.62 (6)O12—Tb—Navi115.25 (4)
O9i—Na—O1109.61 (6)O11—Tb—Navi49.79 (4)
O6—Na—O1123.18 (6)O6iv—Tb—Navi85.72 (4)
O4i—Na—O10109.00 (6)O4—Tb—Navi40.92 (4)
O9i—Na—O10168.27 (7)O1—Tb—Navi155.88 (4)
O6—Na—O1060.44 (5)O9—Tb—Navi42.38 (4)
O1—Na—O1076.15 (5)O10—Tb—Navi122.57 (4)
O4i—Na—O11i62.55 (5)O3—Tb—Na52.13 (4)
O9i—Na—O11i65.37 (5)O12—Tb—Na86.28 (4)
O6—Na—O11i78.51 (5)O11—Tb—Na108.59 (4)
O1—Na—O11i156.84 (6)O6iv—Tb—Na113.76 (4)
O10—Na—O11i113.41 (6)O4—Tb—Na156.20 (4)
O4i—Na—P1123.36 (5)O1—Tb—Na39.78 (4)
O9i—Na—P1138.81 (6)O9—Tb—Na122.23 (4)
O6—Na—P130.27 (3)O10—Tb—Na41.86 (4)
O1—Na—P1101.34 (5)Navi—Tb—Na153.28 (3)
O10—Na—P130.27 (3)O3—Tb—Naiv127.53 (4)
O11i—Na—P195.15 (4)O12—Tb—Naiv50.51 (4)
O4i—Na—O3151.45 (6)O11—Tb—Naiv144.46 (4)
O9i—Na—O3114.70 (6)O6iv—Tb—Naiv33.06 (4)
O6—Na—O368.08 (5)O4—Tb—Naiv76.60 (3)
O1—Na—O358.34 (5)O1—Tb—Naiv65.71 (4)
O10—Na—O358.91 (4)O9—Tb—Naiv107.72 (4)
O11i—Na—O3144.81 (5)O10—Tb—Naiv124.12 (3)
P1—Na—O360.77 (3)Navi—Tb—Naiv104.11 (3)
O4i—Na—P4ii106.40 (5)Na—Tb—Naiv101.88 (2)
O9i—Na—P4ii25.46 (3)O10—P1—O6116.01 (8)
O6—Na—P4ii89.03 (4)O10—P1—O8v111.91 (7)
O1—Na—P4ii109.94 (5)O6—P1—O8v108.64 (8)
O10—Na—P4ii143.44 (5)O10—P1—O5112.35 (7)
O11i—Na—P4ii75.60 (4)O6—P1—O5108.14 (7)
P1—Na—P4ii117.77 (4)O8v—P1—O598.28 (7)
O3—Na—P4ii92.66 (4)O10—P1—Na59.71 (6)
O4i—Na—P2i22.72 (3)O6—P1—Na56.56 (6)
O9i—Na—P2i97.54 (5)O8v—P1—Na125.86 (6)
O6—Na—P2i138.23 (5)O5—P1—Na135.51 (6)
O1—Na—P2i74.33 (4)O3iv—P2—O4117.55 (8)
O10—Na—P2i93.86 (4)O3iv—P2—O8106.17 (8)
O11i—Na—P2i83.77 (4)O4—P2—O8112.19 (8)
P1—Na—P2i116.91 (4)O3iv—P2—O2110.49 (7)
O3—Na—P2i128.89 (4)O4—P2—O2106.54 (7)
P4ii—Na—P2i122.67 (3)O8—P2—O2102.98 (7)
O4i—Na—P3iii85.41 (4)O3iv—P2—Navi113.14 (6)
O9i—Na—P3iii86.83 (4)O8—P2—Navi139.10 (6)
O6—Na—P3iii140.69 (5)O2—P2—Navi73.82 (5)
O1—Na—P3iii23.52 (3)O11—P3—O1vii119.43 (8)
O10—Na—P3iii99.60 (5)O11—P3—O7viii110.89 (7)
O11i—Na—P3iii139.46 (4)O1vii—P3—O7viii107.72 (7)
P1—Na—P3iii124.20 (4)O11—P3—O5109.95 (7)
O3—Na—P3iii72.62 (4)O1vii—P3—O5104.75 (7)
P4ii—Na—P3iii91.96 (3)O7viii—P3—O5102.65 (7)
P2i—Na—P3iii70.71 (2)O11—P3—Navii139.71 (6)
O4i—Na—Tbi41.45 (3)O7viii—P3—Navii109.24 (5)
O9i—Na—Tbi43.17 (4)O5—P3—Navii63.70 (5)
O6—Na—Tbi118.09 (5)O9iv—P4—O12vi118.03 (9)
O1—Na—Tbi118.61 (5)O9iv—P4—O2111.53 (7)
O10—Na—Tbi143.63 (5)O12vi—P4—O2107.41 (8)
O11i—Na—Tbi41.46 (3)O9iv—P4—O7106.24 (7)
P1—Na—Tbi136.04 (4)O12vi—P4—O7110.53 (7)
O3—Na—Tbi157.45 (4)O2—P4—O7101.93 (7)
P4ii—Na—Tbi66.69 (2)O12vi—P4—Naix73.95 (7)
P2i—Na—Tbi62.75 (2)O2—P4—Naix135.52 (6)
P3iii—Na—Tbi98.09 (3)O7—P4—Naix119.55 (6)
O3—Tb—O12138.31 (5)P3iii—O1—Tb141.24 (8)
O3—Tb—O1186.46 (5)P3iii—O1—Na114.86 (8)
O12—Tb—O11113.09 (5)Tb—O1—Na101.72 (5)
O3—Tb—O6iv108.96 (5)P2—O2—P4130.93 (8)
O12—Tb—O6iv83.15 (5)P2x—O3—Tb150.04 (8)
O11—Tb—O6iv135.52 (5)P2x—O3—Na119.88 (7)
O3—Tb—O4146.18 (5)Tb—O3—Na90.04 (4)
O12—Tb—O474.40 (5)P2—O4—Navi119.28 (8)
O11—Tb—O468.11 (4)P2—O4—Tb136.43 (8)
O6iv—Tb—O478.14 (5)Navi—O4—Tb97.62 (5)
O3—Tb—O169.60 (5)P1—O5—P3133.93 (8)
O12—Tb—O176.24 (5)P1—O6—Tbx142.34 (8)
O11—Tb—O1148.01 (5)P1—O6—Na93.17 (7)
O6iv—Tb—O174.31 (5)Tbx—O6—Na115.10 (6)
O4—Tb—O1141.63 (5)P3viii—O7—P4132.38 (8)
O3—Tb—O970.57 (4)P2—O8—P1v139.15 (9)
O12—Tb—O9149.47 (5)P4x—O9—Navi110.04 (8)
O11—Tb—O970.76 (5)P4x—O9—Tb144.13 (8)
O6iv—Tb—O975.61 (5)Navi—O9—Tb94.45 (5)
O4—Tb—O979.89 (4)P1—O10—Tb128.26 (7)
O1—Tb—O9117.48 (5)P1—O10—Na90.02 (7)
O3—Tb—O1070.03 (5)Tb—O10—Na97.96 (5)
O12—Tb—O1080.76 (5)P3—O11—Tb131.68 (8)
O11—Tb—O1072.90 (4)P3—O11—Navi118.15 (8)
O6iv—Tb—O10151.40 (4)Tb—O11—Navi88.75 (5)
O4—Tb—O10119.40 (5)P4i—O12—Tb139.65 (8)

Symmetry codes: (i) x−1, y, z; (ii) x−3/2, −y+1/2, z+1/2; (iii) x−1/2, −y+1/2, z−1/2; (iv) x+1/2, −y+1/2, z−1/2; (v) −x+1, −y, −z+2; (vi) x+1, y, z; (vii) x+1/2, −y+1/2, z+1/2; (viii) −x+2, −y, −z+2; (ix) x+3/2, −y+1/2, z−1/2; (x) x−1/2, −y+1/2, z+1/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: WM2313).

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