Sodium terbium(III) polyphosphate

Oudahmane, A.; Daoud, M.; Tanouti, B.; Avignant, D.; Zambon, D.

doi:10.1107/S1600536810010093

inorganic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 66| Part 4| April 2010| Pages i28-i29

doi:10.1107/S1600536810010093

Open

access

Sodium terbium(III) polyphosphate

Abdelghani Oudahmane,^a Mohamed Daoud,^a Boumediene Tanouti,^a Daniel Avignant ^b ^* and Daniel Zambon ^b

^aUniversité Cadi Ayyad, Laboratoire de Physico-Chimie des Matériaux et Environnement, Faculté des Sciences Semlalia, Département de Chimie, BP 2390, 40000, Marrakech, Morocco, and ^bUniversité Blaise Pascal, Laboratoire des Matériaux Inorganiques, UMR CNRS 6002, 24 Avenue des Landais, 63177 Aubière, France
^*Correspondence e-mail: daniel.avignant@univ-bpclermont.fr

(Received 3 March 2010; accepted 17 March 2010; online 24 March 2010)

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^IB^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^IB^III(PO₃)₄. For corresponding isotypic crystal structures, see: El Masloumi et al. (2005 ) and Zhu et al. (2006 ) for Ln = La; Zhu et al. (2008 ) for Ce and Eu; Horchani-Naifer et al. (2009 ) for Pr; Koizumi et al. (1976 ) for Nd; Amami et al. (2005 ) for Gd; El Masloumi et al. (2008 ) for Y; Amami et al. (2004 ) for Ho; Maksimova et al. (1988 ) for Er. For other isotypic polyphosphates with general composition A^IB^III(PO₃)₄, see: Linde et al. (1983 ) for AB = KCe; Naïli et al. (2006 ) for AgGd; Belam et al. (2007 ) and Jaoudi et al. (2003 ); for NaBi. For a review on the crystal chemistry of polyphosphates, see: Durif (1995 ).

Experimental

Crystal data

NaTb(PO₃)₄
M_r = 497.79
Monoclinic, P 2₁ /n
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 ) 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[F² > 2σ(F²)] = 0.022
wR(F²) = 0.055
S = 1.10
6971 reflections
163 parameters
Δρ_max = 2.12 e Å⁻³
Δρ_min = −2.03 e Å⁻³

Table 1
Selected bond lengths (Å)

P1—O10	1.4896 (14)
P1—O6	1.4918 (13)
P1—O8ⁱ	1.5857 (13)
P1—O5	1.5876 (12)
P2—O3ⁱⁱ	1.4792 (13)
P2—O4	1.4858 (13)
P2—O8	1.5768 (13)
P2—O2	1.5937 (13)
P3—O11	1.4827 (13)
P3—O1ⁱⁱⁱ	1.4868 (13)
P3—O7^iv	1.5897 (13)
P3—O5	1.5915 (13)
P4—O9ⁱⁱ	1.4853 (13)
P4—O12^v	1.4867 (13)
P4—O2	1.5952 (13)
P4—O7	1.5997 (13)
Symmetry codes: (i) -x+1, -y, -z+2; (ii) $[x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ ; (iii) $[x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ ; (iv) -x+2, -y, -z+2; (v) x+1, y, z.

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

Supporting information

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

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

checkCIF report

Comment top

It is now well established that long-chain polyphosphates with general formula A^IB^III(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 A^IB^III 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).

Related literature top

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

Experimental top

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.

Computing details top

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

Figures top

	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, z.
	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 to two adjacent rows. c) view showing the shift (p/2) of one chain relative to the other.

Sodium terbium polytetraphosphate top

Crystal data top

NaTb(PO₃)₄	F(000) = 928
M_r = 497.79	D_x = 3.622 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 27177 reflections
a = 7.1712 (1) Å	θ = 3.5–43.9°
b = 13.0512 (2) Å	µ = 8.56 mm⁻¹
c = 9.7547 (1) Å	T = 296 K
β = 90.604 (1)°	Needle, colourless
V = 912.92 (2) Å³	0.41 × 0.12 × 0.10 mm
Z = 4

Data collection top

Bruker APEXII CCD diffractometer	6971 independent reflections
Radiation source: fine-focus sealed tube	6445 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.025
Detector resolution: 8.3333 pixels mm^-1	θ_max = 43.8°, θ_min = 3.5°
ω and ϕ scans	h = −13→8
Absorption correction: multi-scan (SADABS; Bruker, 2008)	k = −25→17
T_min = 0.127, T_max = 0.478	l = −19→18
26640 measured reflections

Refinement top

Refinement on F²	0 constraints
Least-squares matrix: full	Primary atom site location: structure-invariant direct methods
R[F² > 2σ(F²)] = 0.022	Secondary atom site location: difference Fourier map
wR(F²) = 0.055	w = 1/[σ²(F_o²) + (0.0212P)² + 1.888P] where P = (F_o² + 2F_c²)/3
S = 1.10	(Δ/σ)_max = 0.003
6971 reflections	Δρ_max = 2.12 e Å⁻³
163 parameters	Δρ_min = −2.03 e Å⁻³
0 restraints

Crystal data top

NaTb(PO₃)₄	V = 912.92 (2) Å³
M_r = 497.79	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 7.1712 (1) Å	µ = 8.56 mm⁻¹
b = 13.0512 (2) Å	T = 296 K
c = 9.7547 (1) Å	0.41 × 0.12 × 0.10 mm
β = 90.604 (1)°

Data collection top

Bruker APEXII CCD diffractometer	6971 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2008)	6445 reflections with I > 2σ(I)
T_min = 0.127, T_max = 0.478	R_int = 0.025
26640 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.022	163 parameters
wR(F²) = 0.055	0 restraints
S = 1.10	Δρ_max = 2.12 e Å⁻³
6971 reflections	Δρ_min = −2.03 e Å⁻³

Special details top

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) top

	x	y	z	U_iso*/U_eq
Na	−0.00068 (15)	0.22179 (9)	1.06373 (11)	0.02105 (19)
Tb	0.512736 (10)	0.219027 (5)	0.976594 (7)	0.00611 (2)
P1	0.24948 (6)	0.10137 (3)	1.24460 (4)	0.00585 (6)
P2	0.87630 (6)	0.11488 (3)	0.76336 (4)	0.00525 (5)
P3	0.64720 (6)	0.12784 (3)	1.30443 (4)	0.00514 (5)
P4	1.26813 (6)	0.09081 (3)	0.69983 (4)	0.00584 (6)
O1	0.22211 (18)	0.28938 (9)	0.89407 (14)	0.01015 (19)
O2	1.08668 (17)	0.08115 (10)	0.79214 (13)	0.00956 (18)
O3	0.36683 (19)	0.31058 (10)	1.14928 (13)	0.01003 (18)
O4	0.79883 (18)	0.14688 (10)	0.89738 (13)	0.00974 (18)
O5	0.42970 (17)	0.12511 (10)	1.33504 (13)	0.00876 (17)
O6	0.09345 (18)	0.16584 (10)	1.29625 (14)	0.01081 (19)
O7	1.28234 (19)	−0.02144 (9)	0.63492 (13)	0.01000 (19)
O8	0.7833 (2)	0.01335 (10)	0.70784 (14)	0.01089 (19)
O9	0.73740 (19)	0.33790 (10)	1.08306 (14)	0.01139 (19)
O10	0.28652 (19)	0.10837 (10)	1.09492 (13)	0.01001 (18)
O11	0.67772 (19)	0.13293 (10)	1.15449 (13)	0.01040 (19)
O12	0.42899 (18)	0.11069 (11)	0.79349 (15)	0.0125 (2)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Na	0.0165 (4)	0.0309 (5)	0.0157 (4)	0.0077 (3)	−0.0022 (3)	0.0012 (3)
Tb	0.00563 (3)	0.00740 (3)	0.00529 (3)	0.00035 (2)	0.00018 (2)	−0.00028 (2)
P1	0.00480 (13)	0.00573 (13)	0.00703 (14)	−0.00036 (10)	0.00008 (10)	−0.00060 (11)
P2	0.00561 (13)	0.00468 (12)	0.00548 (13)	0.00011 (10)	0.00126 (10)	0.00071 (10)
P3	0.00532 (13)	0.00475 (12)	0.00534 (13)	−0.00013 (10)	−0.00051 (10)	−0.00029 (10)
P4	0.00542 (13)	0.00510 (13)	0.00700 (14)	0.00056 (10)	0.00050 (10)	0.00007 (11)
O1	0.0087 (4)	0.0083 (4)	0.0134 (5)	0.0018 (3)	−0.0021 (4)	0.0039 (4)
O2	0.0055 (4)	0.0131 (5)	0.0101 (4)	0.0020 (3)	0.0015 (3)	0.0033 (4)
O3	0.0113 (5)	0.0089 (4)	0.0100 (4)	−0.0008 (4)	0.0020 (3)	−0.0047 (4)
O4	0.0090 (4)	0.0131 (5)	0.0071 (4)	0.0025 (4)	0.0029 (3)	−0.0016 (4)
O5	0.0052 (4)	0.0133 (5)	0.0077 (4)	−0.0013 (3)	−0.0003 (3)	−0.0016 (4)
O6	0.0076 (4)	0.0113 (5)	0.0135 (5)	0.0027 (4)	0.0004 (3)	−0.0030 (4)
O7	0.0151 (5)	0.0058 (4)	0.0090 (4)	0.0031 (4)	−0.0026 (4)	−0.0009 (3)
O8	0.0137 (5)	0.0067 (4)	0.0123 (5)	−0.0031 (4)	−0.0005 (4)	−0.0007 (4)
O9	0.0130 (5)	0.0094 (4)	0.0118 (5)	−0.0029 (4)	0.0043 (4)	−0.0046 (4)
O10	0.0121 (5)	0.0105 (4)	0.0074 (4)	−0.0018 (4)	−0.0006 (3)	−0.0001 (3)
O11	0.0106 (5)	0.0140 (5)	0.0066 (4)	0.0017 (4)	0.0009 (3)	0.0027 (4)
O12	0.0070 (4)	0.0156 (5)	0.0149 (5)	−0.0001 (4)	−0.0020 (4)	−0.0064 (4)

Geometric parameters (Å, º) top

Na—O4ⁱ	2.3680 (17)	P2—O4	1.4858 (13)
Na—O9ⁱ	2.4223 (17)	P2—O8	1.5768 (13)
Na—O6	2.4700 (17)	P2—O2	1.5937 (13)
Na—O1	2.4750 (18)	P2—Na^vi	3.3550 (12)
Na—O10	2.5520 (17)	P3—O11	1.4827 (13)
Na—O11ⁱ	2.7369 (18)	P3—O1^vii	1.4868 (13)
Na—P1	2.9554 (11)	P3—O7^viii	1.5897 (13)
Na—O3	2.9897 (17)	P3—O5	1.5915 (13)
Na—P4ⁱⁱ	3.2464 (11)	P3—Na^vii	3.3808 (12)
Na—P2ⁱ	3.3550 (12)	P4—O9^iv	1.4853 (13)
Na—P3ⁱⁱⁱ	3.3808 (12)	P4—O12^vi	1.4867 (13)
Tb—O3	2.3232 (12)	P4—O2	1.5952 (13)
Tb—O12	2.3511 (13)	P4—O7	1.5997 (13)
Tb—O11	2.3729 (12)	P4—Na^ix	3.2464 (12)
Tb—O6^iv	2.3894 (13)	O1—P3ⁱⁱⁱ	1.4868 (12)
Tb—O4	2.3930 (12)	O3—P2^x	1.4792 (13)
Tb—O1	2.4082 (12)	O4—Na^vi	2.3680 (17)
Tb—O9	2.4589 (13)	O6—Tb^x	2.3894 (13)
Tb—O10	2.4676 (13)	O7—P3^viii	1.5897 (13)
P1—O10	1.4896 (14)	O8—P1^v	1.5857 (13)
P1—O6	1.4918 (13)	O9—P4^x	1.4853 (13)
P1—O8^v	1.5857 (13)	O9—Na^vi	2.4223 (17)
P1—O5	1.5876 (12)	O11—Na^vi	2.7369 (18)
P2—O3^iv	1.4792 (13)	O12—P4ⁱ	1.4867 (13)

O4ⁱ—Na—O9ⁱ	81.14 (5)	O1—Tb—O10	78.97 (4)
O4ⁱ—Na—O6	131.70 (7)	O9—Tb—O10	127.07 (4)
O9ⁱ—Na—O6	108.55 (6)	O3—Tb—Na^vi	105.53 (4)
O4ⁱ—Na—O1	94.62 (6)	O12—Tb—Na^vi	115.25 (4)
O9ⁱ—Na—O1	109.61 (6)	O11—Tb—Na^vi	49.79 (4)
O6—Na—O1	123.18 (6)	O6^iv—Tb—Na^vi	85.72 (4)
O4ⁱ—Na—O10	109.00 (6)	O4—Tb—Na^vi	40.92 (4)
O9ⁱ—Na—O10	168.27 (7)	O1—Tb—Na^vi	155.88 (4)
O6—Na—O10	60.44 (5)	O9—Tb—Na^vi	42.38 (4)
O1—Na—O10	76.15 (5)	O10—Tb—Na^vi	122.57 (4)
O4ⁱ—Na—O11ⁱ	62.55 (5)	O3—Tb—Na	52.13 (4)
O9ⁱ—Na—O11ⁱ	65.37 (5)	O12—Tb—Na	86.28 (4)
O6—Na—O11ⁱ	78.51 (5)	O11—Tb—Na	108.59 (4)
O1—Na—O11ⁱ	156.84 (6)	O6^iv—Tb—Na	113.76 (4)
O10—Na—O11ⁱ	113.41 (6)	O4—Tb—Na	156.20 (4)
O4ⁱ—Na—P1	123.36 (5)	O1—Tb—Na	39.78 (4)
O9ⁱ—Na—P1	138.81 (6)	O9—Tb—Na	122.23 (4)
O6—Na—P1	30.27 (3)	O10—Tb—Na	41.86 (4)
O1—Na—P1	101.34 (5)	Na^vi—Tb—Na	153.28 (3)
O10—Na—P1	30.27 (3)	O3—Tb—Na^iv	127.53 (4)
O11ⁱ—Na—P1	95.15 (4)	O12—Tb—Na^iv	50.51 (4)
O4ⁱ—Na—O3	151.45 (6)	O11—Tb—Na^iv	144.46 (4)
O9ⁱ—Na—O3	114.70 (6)	O6^iv—Tb—Na^iv	33.06 (4)
O6—Na—O3	68.08 (5)	O4—Tb—Na^iv	76.60 (3)
O1—Na—O3	58.34 (5)	O1—Tb—Na^iv	65.71 (4)
O10—Na—O3	58.91 (4)	O9—Tb—Na^iv	107.72 (4)
O11ⁱ—Na—O3	144.81 (5)	O10—Tb—Na^iv	124.12 (3)
P1—Na—O3	60.77 (3)	Na^vi—Tb—Na^iv	104.11 (3)
O4ⁱ—Na—P4ⁱⁱ	106.40 (5)	Na—Tb—Na^iv	101.88 (2)
O9ⁱ—Na—P4ⁱⁱ	25.46 (3)	O10—P1—O6	116.01 (8)
O6—Na—P4ⁱⁱ	89.03 (4)	O10—P1—O8^v	111.91 (7)
O1—Na—P4ⁱⁱ	109.94 (5)	O6—P1—O8^v	108.64 (8)
O10—Na—P4ⁱⁱ	143.44 (5)	O10—P1—O5	112.35 (7)
O11ⁱ—Na—P4ⁱⁱ	75.60 (4)	O6—P1—O5	108.14 (7)
P1—Na—P4ⁱⁱ	117.77 (4)	O8^v—P1—O5	98.28 (7)
O3—Na—P4ⁱⁱ	92.66 (4)	O10—P1—Na	59.71 (6)
O4ⁱ—Na—P2ⁱ	22.72 (3)	O6—P1—Na	56.56 (6)
O9ⁱ—Na—P2ⁱ	97.54 (5)	O8^v—P1—Na	125.86 (6)
O6—Na—P2ⁱ	138.23 (5)	O5—P1—Na	135.51 (6)
O1—Na—P2ⁱ	74.33 (4)	O3^iv—P2—O4	117.55 (8)
O10—Na—P2ⁱ	93.86 (4)	O3^iv—P2—O8	106.17 (8)
O11ⁱ—Na—P2ⁱ	83.77 (4)	O4—P2—O8	112.19 (8)
P1—Na—P2ⁱ	116.91 (4)	O3^iv—P2—O2	110.49 (7)
O3—Na—P2ⁱ	128.89 (4)	O4—P2—O2	106.54 (7)
P4ⁱⁱ—Na—P2ⁱ	122.67 (3)	O8—P2—O2	102.98 (7)
O4ⁱ—Na—P3ⁱⁱⁱ	85.41 (4)	O3^iv—P2—Na^vi	113.14 (6)
O9ⁱ—Na—P3ⁱⁱⁱ	86.83 (4)	O8—P2—Na^vi	139.10 (6)
O6—Na—P3ⁱⁱⁱ	140.69 (5)	O2—P2—Na^vi	73.82 (5)
O1—Na—P3ⁱⁱⁱ	23.52 (3)	O11—P3—O1^vii	119.43 (8)
O10—Na—P3ⁱⁱⁱ	99.60 (5)	O11—P3—O7^viii	110.89 (7)
O11ⁱ—Na—P3ⁱⁱⁱ	139.46 (4)	O1^vii—P3—O7^viii	107.72 (7)
P1—Na—P3ⁱⁱⁱ	124.20 (4)	O11—P3—O5	109.95 (7)
O3—Na—P3ⁱⁱⁱ	72.62 (4)	O1^vii—P3—O5	104.75 (7)
P4ⁱⁱ—Na—P3ⁱⁱⁱ	91.96 (3)	O7^viii—P3—O5	102.65 (7)
P2ⁱ—Na—P3ⁱⁱⁱ	70.71 (2)	O11—P3—Na^vii	139.71 (6)
O4ⁱ—Na—Tbⁱ	41.45 (3)	O7^viii—P3—Na^vii	109.24 (5)
O9ⁱ—Na—Tbⁱ	43.17 (4)	O5—P3—Na^vii	63.70 (5)
O6—Na—Tbⁱ	118.09 (5)	O9^iv—P4—O12^vi	118.03 (9)
O1—Na—Tbⁱ	118.61 (5)	O9^iv—P4—O2	111.53 (7)
O10—Na—Tbⁱ	143.63 (5)	O12^vi—P4—O2	107.41 (8)
O11ⁱ—Na—Tbⁱ	41.46 (3)	O9^iv—P4—O7	106.24 (7)
P1—Na—Tbⁱ	136.04 (4)	O12^vi—P4—O7	110.53 (7)
O3—Na—Tbⁱ	157.45 (4)	O2—P4—O7	101.93 (7)
P4ⁱⁱ—Na—Tbⁱ	66.69 (2)	O12^vi—P4—Na^ix	73.95 (7)
P2ⁱ—Na—Tbⁱ	62.75 (2)	O2—P4—Na^ix	135.52 (6)
P3ⁱⁱⁱ—Na—Tbⁱ	98.09 (3)	O7—P4—Na^ix	119.55 (6)
O3—Tb—O12	138.31 (5)	P3ⁱⁱⁱ—O1—Tb	141.24 (8)
O3—Tb—O11	86.46 (5)	P3ⁱⁱⁱ—O1—Na	114.86 (8)
O12—Tb—O11	113.09 (5)	Tb—O1—Na	101.72 (5)
O3—Tb—O6^iv	108.96 (5)	P2—O2—P4	130.93 (8)
O12—Tb—O6^iv	83.15 (5)	P2^x—O3—Tb	150.04 (8)
O11—Tb—O6^iv	135.52 (5)	P2^x—O3—Na	119.88 (7)
O3—Tb—O4	146.18 (5)	Tb—O3—Na	90.04 (4)
O12—Tb—O4	74.40 (5)	P2—O4—Na^vi	119.28 (8)
O11—Tb—O4	68.11 (4)	P2—O4—Tb	136.43 (8)
O6^iv—Tb—O4	78.14 (5)	Na^vi—O4—Tb	97.62 (5)
O3—Tb—O1	69.60 (5)	P1—O5—P3	133.93 (8)
O12—Tb—O1	76.24 (5)	P1—O6—Tb^x	142.34 (8)
O11—Tb—O1	148.01 (5)	P1—O6—Na	93.17 (7)
O6^iv—Tb—O1	74.31 (5)	Tb^x—O6—Na	115.10 (6)
O4—Tb—O1	141.63 (5)	P3^viii—O7—P4	132.38 (8)
O3—Tb—O9	70.57 (4)	P2—O8—P1^v	139.15 (9)
O12—Tb—O9	149.47 (5)	P4^x—O9—Na^vi	110.04 (8)
O11—Tb—O9	70.76 (5)	P4^x—O9—Tb	144.13 (8)
O6^iv—Tb—O9	75.61 (5)	Na^vi—O9—Tb	94.45 (5)
O4—Tb—O9	79.89 (4)	P1—O10—Tb	128.26 (7)
O1—Tb—O9	117.48 (5)	P1—O10—Na	90.02 (7)
O3—Tb—O10	70.03 (5)	Tb—O10—Na	97.96 (5)
O12—Tb—O10	80.76 (5)	P3—O11—Tb	131.68 (8)
O11—Tb—O10	72.90 (4)	P3—O11—Na^vi	118.15 (8)
O6^iv—Tb—O10	151.40 (4)	Tb—O11—Na^vi	88.75 (5)
O4—Tb—O10	119.40 (5)	P4ⁱ—O12—Tb	139.65 (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.

Experimental details

Crystal data
Chemical formula	NaTb(PO₃)₄
M_r	497.79
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	296
a, b, c (Å)	7.1712 (1), 13.0512 (2), 9.7547 (1)
β (°)	90.604 (1)
V (Å³)	912.92 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	8.56
Crystal size (mm)	0.41 × 0.12 × 0.10

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2008)
T_min, T_max	0.127, 0.478
No. of measured, independent and observed [I > 2σ(I)] reflections	26640, 6971, 6445
R_int	0.025
(sin θ/λ)_max (Å⁻¹)	0.974

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.022, 0.055, 1.10
No. of reflections	6971
No. of parameters	163
Δρ_max, Δρ_min (e Å⁻³)	2.12, −2.03

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 1999), SHELXTL (Sheldrick, 2008).

Selected bond lengths (Å) top

P1—O10	1.4896 (14)	P3—O11	1.4827 (13)
P1—O6	1.4918 (13)	P3—O1ⁱⁱⁱ	1.4868 (13)
P1—O8ⁱ	1.5857 (13)	P3—O7^iv	1.5897 (13)
P1—O5	1.5876 (12)	P3—O5	1.5915 (13)
P2—O3ⁱⁱ	1.4792 (13)	P4—O9ⁱⁱ	1.4853 (13)
P2—O4	1.4858 (13)	P4—O12^v	1.4867 (13)
P2—O8	1.5768 (13)	P4—O2	1.5952 (13)
P2—O2	1.5937 (13)	P4—O7	1.5997 (13)

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, z.

References

Amami, J., Férid, M. & Trabelsi-Ayedi, M. (2005). Mater. Res. Bull. 40, 2144–2152. Web of Science CrossRef CAS Google Scholar
Amami, J., Horchani, K., Merle, D. & Férid, M. (2004). J. Phys. IV Fr. 122, 111–115. CrossRef CAS Google Scholar
Belam, W., Ben Nasr, C. & Sanz, J. (2007). Ann. Chim. Paris, 32, 45–54. Web of Science CrossRef CAS Google Scholar
Brandenburg, K. (1999). DIAMOND. Crystal Impact GbR, Bonn, Germany. Google Scholar
Bruker (2008). SADABS, APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Durif, A. (1995). Crystal Chemistry of Condensed Phosphates. New York and London: Plenum Press. Google Scholar
El Masloumi, M., Imaz, I., Chaminade, J. P., Videau, J. J., Couzi, M., Mesnaoui, M. & Maazaz, M. (2005). J. Solid State Chem. 178, 3581–3588. CAS Google Scholar
El Masloumi, M., Jubera, V., Pechev, S., Chaminade, J. P., Videau, J. J., Mesnaoui, M., Maazaz, M. & Moine, B. (2008). J. Solid State Chem. 181, 3078–3085. Web of Science CrossRef CAS Google Scholar
Horchani-Naifer, K., Amami, J. & Férid, M. (2009). J. Rare Earths, 27, 1–8. Web of Science CrossRef Google Scholar
Jaoudi, K., Naïli, H., Zouari, N., Mhiri, T. & Daoud, A. (2003). J. Alloys Compd, 354, 104–114. Google Scholar
Koizumi, H. (1976). Acta Cryst. B32, 2254–2256. CrossRef CAS IUCr Journals Web of Science Google Scholar
Linde, S. A., Gorbunova, Y. E. & Lavrov, A. V. (1983). Zh. Neorg. Khim. 28, 1426–1430. CAS Google Scholar
Maksimova, S., Masloboev, V. A., Palkina, K. K., Sazhenkov, A. A. & Chibiskova, N. T. (1988). Zh. Neorg. Khim. 33, 2503–2505. CAS Google Scholar
Naïli, H., Ettis, H. & Mhiri, T. (2006). J. Alloys Compd, 424, 400–407. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Zhu, J., Cheng, W. D., Wu, D. S., Zhang, H., Gong, Y. J. & Tong, H. N. (2006). J. Solid State Chem. 179, 597–604. Web of Science CrossRef CAS Google Scholar
Zhu, J., Cheng, W. D., Wu, D. S., Zhang, H., Gong, Y. J., Tong, H. N. & Zhao, D. (2008). J. Alloys Compd, 454, 419–426. Web of Science CrossRef CAS Google Scholar