Aluminium cyclo-hexa-phosphate.

Single crystals of the title compound, Al(2)P(6)O(18), were obtained by solid-state reaction. The monoclinic structure is isotypic with its Cr(III), Ga(III) and Ru(III) analogues and is built up of six-membered phosphate ring anions, P(6)O(18) (6-), isolated from each other and further linked by isolated AlO(6) octa-hedra by sharing corners. Each AlO(6) octa-hedron is linked to four P(6)O(18) (6-) rings. More accurately, two rings are linked through bidentate diphosphate groups attached in the cis-positions to the AlO(6) octa-hedron. The other two rings are linked to the two remaining corners, also in cis-positions of the AlO(6) octa-hedron.

Related literature

The title compound was first synthesized by Kanene et al. (1985 ▶) and its unit cell determined from Weissenberg photographs. Isotypic compounds have been reported: Ga2P6O18 (Chudinova et al., 1987 ▶); Cr2P6O18 (Bagieu-Beucher & Guitel, 1977 ▶) and Ru2P6O18 (Fukuoka et al., 1995 ▶). For a review of the crystal chemistry of cyclo­hexa­phosphates, see: Durif (1995 ▶, 2005 ▶). For applications of aluminium phosphate, see: Vippola et al. (2000 ▶). For the structures of other cyclo­hexa­phosphates with the P6O18 6− anion, see: Averbuch-Pouchot & Durif (1991a ▶,b ▶,c ▶).

Experimental

Crystal data

Al2P6O18

M = 527.79

Monoclinic,

a = 6.0931 (2) Å

b = 15.0676 (4) Å

c = 8.2016 (3) Å

β = 105.166 (1)°

V = 726.75 (4) Å3

Z = 2

Mo Kα radiation

μ = 0.96 mm−1

T = 296 K

0.16 × 0.07 × 0.06 mm

Data collection

Bruker APEXII CCD diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2008 ▶) T min = 0.860, T max = 0.945

6548 measured reflections

1674 independent reflections

1398 reflections with I > 2σ(I)

R int = 0.035

Refinement

R[F 2 > 2σ(F 2)] = 0.032

wR(F 2) = 0.130

S = 1.16

1674 reflections

118 parameters

Δρmax = 0.56 e Å−3

Δρmin = −0.71 e Å−3

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: CaRine (Boudias & Monceau, 1998 ▶) and ORTEP-3 (Farrugia, 1997 ▶); software used to prepare material for publication: SHELXTL.

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810005374/wm2303sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810005374/wm2303Isup2.hkl

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

Al2P6O18	F(000) = 520
Mr = 527.79	Dx = 2.412 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2041 reflections
a = 6.0931 (2) Å	θ = 3.5–27.5°
b = 15.0676 (4) Å	µ = 0.96 mm−1
c = 8.2016 (3) Å	T = 296 K
β = 105.166 (1)°	Rhombic, colourless
V = 726.75 (4) Å3	0.16 × 0.07 × 0.06 mm
Z = 2

Bruker APEXII CCD diffractometer	1674 independent reflections
Radiation source: fine-focus sealed tube	1398 reflections with I > 2σ(I)
graphite	Rint = 0.035
Detector resolution: 8.3333 pixels mm-1	θmax = 27.5°, θmin = 2.7°
φ and ω scans	h = −7→7
Absorption correction: multi-scan (SADABS; Bruker, 2008)	k = −11→19
Tmin = 0.860, Tmax = 0.945	l = −10→10
6548 measured reflections

Refinement on F2	0 restraints
Least-squares matrix: full	Primary atom site location: structure-invariant direct methods
R[F2 > 2σ(F2)] = 0.032	Secondary atom site location: difference Fourier map
wR(F2) = 0.130	w = 1/[σ2(Fo2) + (0.0787P)2 + 0.2264P] where P = (Fo2 + 2Fc2)/3
S = 1.16	(Δ/σ)max < 0.001
1674 reflections	Δρmax = 0.56 e Å−3
118 parameters	Δρmin = −0.71 e Å−3

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.

	x	y	z	Uiso*/Ueq
P1	0.70149 (15)	0.33738 (5)	0.01706 (11)	0.0049 (2)
P2	0.64525 (14)	0.04431 (5)	0.21869 (11)	0.0050 (2)
P3	0.08497 (14)	0.11301 (5)	−0.20937 (11)	0.0054 (2)
Al	0.61549 (17)	0.13831 (6)	−0.12313 (13)	0.0046 (3)
O1	0.3051 (4)	0.15855 (15)	−0.1454 (3)	0.0082 (5)
O2	−0.0766 (4)	0.11484 (16)	−0.1026 (3)	0.0090 (5)
O3	0.6755 (4)	0.25850 (15)	−0.0920 (3)	0.0078 (5)
O4	0.6653 (4)	0.12162 (15)	0.1117 (3)	0.0076 (5)
O5	0.5656 (4)	0.34555 (16)	0.1415 (3)	0.0084 (5)
O6	0.4448 (4)	−0.01495 (15)	0.1608 (3)	0.0073 (5)
O7	0.6509 (5)	0.42395 (15)	−0.0967 (3)	0.0109 (5)
O8	0.8737 (4)	−0.01227 (15)	0.2539 (3)	0.0110 (5)
O9	0.9653 (4)	0.34779 (16)	0.1085 (3)	0.0107 (5)

	U11	U22	U33	U12	U13	U23
P1	0.0052 (5)	0.0050 (4)	0.0042 (5)	−0.0007 (3)	0.0008 (3)	0.0001 (3)
P2	0.0060 (5)	0.0041 (4)	0.0050 (5)	−0.0003 (3)	0.0014 (3)	−0.0009 (3)
P3	0.0036 (5)	0.0058 (4)	0.0069 (5)	0.0007 (3)	0.0015 (3)	0.0002 (3)
Al	0.0034 (5)	0.0055 (5)	0.0052 (5)	−0.0006 (4)	0.0015 (4)	−0.0003 (3)
O1	0.0045 (12)	0.0065 (12)	0.0136 (13)	−0.0012 (9)	0.0025 (10)	−0.0021 (9)
O2	0.0050 (12)	0.0127 (12)	0.0094 (13)	−0.0002 (9)	0.0024 (10)	0.0014 (10)
O3	0.0110 (13)	0.0045 (11)	0.0077 (12)	−0.0028 (9)	0.0020 (10)	−0.0015 (9)
O4	0.0119 (13)	0.0059 (11)	0.0053 (12)	−0.0022 (9)	0.0025 (10)	−0.0007 (9)
O5	0.0066 (13)	0.0132 (12)	0.0057 (12)	0.0000 (9)	0.0020 (10)	0.0003 (9)
O6	0.0060 (12)	0.0063 (12)	0.0098 (12)	0.0002 (9)	0.0025 (10)	−0.0012 (9)
O7	0.0221 (15)	0.0059 (12)	0.0053 (12)	0.0033 (9)	0.0045 (11)	0.0022 (9)
O8	0.0061 (12)	0.0073 (12)	0.0175 (14)	−0.0004 (9)	−0.0007 (10)	−0.0038 (9)
O9	0.0052 (13)	0.0186 (13)	0.0084 (13)	−0.0021 (10)	0.0019 (10)	−0.0062 (10)

P1—O3	1.471 (2)	Al—O3	1.852 (2)
P1—O5	1.478 (2)	Al—O2iv	1.873 (3)
P1—O7	1.587 (2)	Al—O1	1.877 (3)
P1—O9	1.594 (3)	Al—O4	1.887 (3)
P2—O4	1.482 (2)	Al—O5v	1.889 (3)
P2—O6	1.487 (2)	Al—O6iii	1.904 (2)
P2—O7i	1.579 (2)	O2—Alvi	1.873 (3)
P2—O8	1.593 (2)	O5—Ali	1.889 (3)
P3—O1	1.476 (2)	O6—Aliii	1.904 (2)
P3—O2	1.479 (3)	O7—P2v	1.579 (2)
P3—O9ii	1.594 (2)	O8—P3iii	1.597 (2)
P3—O8iii	1.597 (2)	O9—P3vii	1.594 (3)
O3—P1—O5	119.77 (14)	O3—Al—O4	90.93 (11)
O3—P1—O7	109.47 (14)	O2iv—Al—O4	89.61 (11)
O5—P1—O7	106.27 (14)	O1—Al—O4	90.56 (12)
O3—P1—O9	107.50 (14)	O3—Al—O5v	89.33 (11)
O5—P1—O9	110.17 (14)	O2iv—Al—O5v	90.32 (11)
O7—P1—O9	102.27 (14)	O1—Al—O5v	89.50 (11)
O4—P2—O6	118.09 (14)	O4—Al—O5v	179.74 (12)
O4—P2—O7i	110.17 (13)	O3—Al—O6iii	178.54 (12)
O6—P2—O7i	107.36 (14)	O2iv—Al—O6iii	88.66 (11)
O4—P2—O8	108.93 (14)	O1—Al—O6iii	89.77 (11)
O6—P2—O8	110.01 (13)	O4—Al—O6iii	90.46 (11)
O7i—P2—O8	100.91 (14)	O5v—Al—O6iii	89.29 (11)
O1—P3—O2	117.68 (15)	P3—O1—Al	139.30 (16)
O1—P3—O9ii	108.14 (14)	P3—O2—Alvi	139.15 (17)
O2—P3—O9ii	109.62 (14)	P1—O3—Al	149.33 (16)
O1—P3—O8iii	109.89 (14)	P2—O4—Al	133.84 (15)
O2—P3—O8iii	108.82 (14)	P1—O5—Ali	138.32 (16)
O9ii—P3—O8iii	101.47 (14)	P2—O6—Aliii	138.20 (15)
O3—Al—O2iv	90.88 (11)	P2v—O7—P1	139.91 (16)
O3—Al—O1	90.69 (11)	P2—O8—P3iii	130.56 (16)
O2iv—Al—O1	178.43 (11)	P1—O9—P3vii	129.42 (16)

P1—O3	1.471 (2)
P1—O5	1.478 (2)
P1—O7	1.587 (2)
P1—O9	1.594 (3)
P2—O4	1.482 (2)
P2—O6	1.487 (2)
P2—O7i	1.579 (2)
P2—O8	1.593 (2)
P3—O1	1.476 (2)
P3—O2	1.479 (3)
P3—O9ii	1.594 (2)
P3—O8iii	1.597 (2)
Al—O3	1.852 (2)
Al—O2iv	1.873 (3)
Al—O1	1.877 (3)
Al—O4	1.887 (3)
Al—O5v	1.889 (3)
Al—O6iii	1.904 (2)

P2v—O7—P1	139.91 (16)
P2—O8—P3iii	130.56 (16)
P1—O9—P3vi	129.42 (16)

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) ; (v) ; (vi) .