The crystal structure of cerium catena-polyphosphate, CeP3O9, is isotypic with the previously reported structures of La, Pr, Nd and Gd C-type polyphosphates. The absolute configuration of CeP3O9 was determined reliably. The structure contains helical polyphosphate chains with a period of six tetrahedra running along the c axis, and the Ce cation is in an eightfold coordination by terminal O atoms of the polyphosphate chains. Ce, one P and one O atom are located on twofold rotation axes.
Supporting information
Key indicators
- Single-crystal X-ray study
- T = 180 K
- Mean (P-O) = 0.003 Å
- R factor = 0.025
- wR factor = 0.055
- Data-to-parameter ratio = 11.2
checkCIF/PLATON results
No syntax errors found
Alert level A
PLAT029_ALERT_3_A _diffrn_measured_fraction_theta_full Low ....... 0.92
| Author Response: This is only just on the low side for any global regulation;
and 0.92 coverage is satisfactory for this sized-compound. There were
time limitations, and it was thought better to collect a few Friedels
than concentrate on excessive coverage.
|
Alert level B
PLAT213_ALERT_2_B Atom O3 has ADP max/min Ratio ............. 4.20 prola
Alert level C
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor .... 2.91
Alert level G
REFLT03_ALERT_4_G WARNING: Large fraction of Friedel related reflns may
be needed to determine absolute structure
From the CIF: _diffrn_reflns_theta_max 27.43
From the CIF: _reflns_number_total 686
Count of symmetry unique reflns 488
Completeness (_total/calc) 140.57%
TEST3: Check Friedels for noncentro structure
Estimate of Friedel pairs measured 198
Fraction of Friedel pairs measured 0.406
Are heavy atom types Z>Si present yes
PLAT794_ALERT_5_G Check Predicted Bond Valency for Ce1 (3) 3.33
1 ALERT level A = In general: serious problem
1 ALERT level B = Potentially serious problem
1 ALERT level C = Check and explain
2 ALERT level G = General alerts; check
0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
2 ALERT type 2 Indicator that the structure model may be wrong or deficient
1 ALERT type 3 Indicator that the structure quality may be low
1 ALERT type 4 Improvement, methodology, query or suggestion
1 ALERT type 5 Informative message, check
Data collection: COLLECT (Nonius, 1998); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: SCALEPACK and DENZO (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ATOMS (Dowty, 2006); software used to prepare material for publication: SHELXL97.
Cerium
catena-polyphosphate
top
Crystal data top
CeP3O9 | F(000) = 700 |
Mr = 377.03 | Dx = 3.524 Mg m−3 |
Orthorhombic, C2221 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: C 2c 2 | Cell parameters from 1840 reflections |
a = 11.236 (2) Å | θ = 1.0–27.5° |
b = 8.6110 (17) Å | µ = 7.10 mm−1 |
c = 7.3458 (15) Å | T = 180 K |
V = 710.7 (2) Å3 | Trianglar plate, translucent white |
Z = 4 | 0.15 × 0.10 × 0.05 mm |
Data collection top
Nonius Kappa-CCD diffractometer | 686 independent reflections |
Radiation source: fine-focus sealed tube | 658 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.037 |
φ scans | θmax = 27.4°, θmin = 4.1° |
Absorption correction: multi-scan (SORTAV; Blessing, 1995) | h = −10→14 |
Tmin = 0.461, Tmax = 0.700 | k = −10→10 |
1045 measured reflections | l = −9→9 |
Refinement top
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.025 | w = 1/[σ2(Fo2) + 0.1886P] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.055 | (Δ/σ)max < 0.001 |
S = 1.05 | Δρmax = 0.78 e Å−3 |
686 reflections | Δρmin = −1.38 e Å−3 |
61 parameters | Absolute structure: Flack (1983), 198 Friedel pairs |
0 restraints | Absolute structure parameter: −0.06 (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 | x | y | z | Uiso*/Ueq | |
Ce1 | 1.0000 | 0.62768 (4) | 0.2500 | 0.00805 (15) | |
P1 | 1.0000 | 0.2484 (2) | 0.2500 | 0.0085 (3) | |
P2 | 0.82530 (12) | 0.9927 (2) | 0.20267 (15) | 0.0104 (3) | |
O1 | 0.6957 (3) | 0.0244 (5) | 0.2102 (4) | 0.0158 (9) | |
O2 | 0.8732 (4) | 0.8506 (5) | 0.2873 (5) | 0.0195 (11) | |
O3 | 0.8751 (4) | 1.0000 | 1.0000 | 0.0168 (12) | |
O4 | 0.0185 (3) | 0.3450 (4) | 0.4175 (4) | 0.0111 (9) | |
O5 | 0.8915 (4) | 0.1381 (4) | 0.2904 (5) | 0.0158 (10) | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
Ce1 | 0.0117 (2) | 0.0098 (2) | 0.0026 (2) | 0.000 | 0.00012 (17) | 0.000 |
P1 | 0.0136 (8) | 0.0098 (7) | 0.0022 (7) | 0.000 | −0.0010 (9) | 0.000 |
P2 | 0.0135 (7) | 0.0118 (6) | 0.0059 (6) | 0.0002 (7) | 0.0005 (4) | −0.0015 (6) |
O1 | 0.0138 (19) | 0.023 (2) | 0.011 (2) | 0.0011 (19) | 0.0020 (14) | −0.0009 (18) |
O2 | 0.025 (2) | 0.0152 (19) | 0.018 (3) | 0.0050 (18) | 0.0039 (17) | −0.0012 (18) |
O3 | 0.016 (3) | 0.033 (3) | 0.002 (2) | 0.000 | 0.000 | −0.002 (3) |
O4 | 0.016 (2) | 0.0145 (15) | 0.0026 (16) | 0.0024 (18) | −0.0027 (15) | 0.0005 (12) |
O5 | 0.019 (2) | 0.023 (2) | 0.006 (2) | −0.005 (2) | 0.0039 (15) | −0.0044 (17) |
Geometric parameters (Å, º) top
Ce1—O1i | 2.390 (4) | P2—O2 | 1.475 (4) |
Ce1—O1ii | 2.390 (4) | P2—O1viii | 1.483 (4) |
Ce1—O2iii | 2.406 (4) | P2—O3ix | 1.592 (2) |
Ce1—O2 | 2.406 (4) | P2—O5viii | 1.593 (4) |
Ce1—O4iv | 2.462 (3) | O1—P2x | 1.483 (4) |
Ce1—O4v | 2.462 (3) | O1—Ce1xi | 2.390 (4) |
Ce1—O4vi | 2.735 (3) | O3—P2xii | 1.592 (2) |
Ce1—O4vii | 2.735 (3) | O3—P2xiii | 1.592 (2) |
Ce1—P1 | 3.2660 (19) | O4—P1xiv | 1.500 (3) |
P1—O4vii | 1.500 (3) | O4—Ce1xv | 2.462 (3) |
P1—O4vi | 1.500 (3) | O4—Ce1xiv | 2.735 (3) |
P1—O5 | 1.573 (4) | O5—P2x | 1.593 (4) |
P1—O5iii | 1.573 (4) | | |
| | | |
O1i—Ce1—O1ii | 136.3 (2) | O2iii—Ce1—P1 | 142.91 (11) |
O1i—Ce1—O2iii | 148.83 (16) | O2—Ce1—P1 | 142.91 (11) |
O1ii—Ce1—O2iii | 74.81 (14) | O4iv—Ce1—P1 | 95.47 (8) |
O1i—Ce1—O2 | 74.81 (14) | O4v—Ce1—P1 | 95.47 (8) |
O1ii—Ce1—O2 | 148.83 (16) | O4vi—Ce1—P1 | 27.15 (6) |
O2iii—Ce1—O2 | 74.2 (2) | O4vii—Ce1—P1 | 27.15 (6) |
O1i—Ce1—O4iv | 94.56 (11) | O4vii—P1—O4vi | 112.6 (3) |
O1ii—Ce1—O4iv | 89.52 (12) | O4vii—P1—O5 | 106.69 (18) |
O2iii—Ce1—O4iv | 82.00 (12) | O4vi—P1—O5 | 112.5 (2) |
O2—Ce1—O4iv | 89.25 (13) | O4vii—P1—O5iii | 112.5 (2) |
O1i—Ce1—O4v | 89.52 (12) | O4vi—P1—O5iii | 106.69 (18) |
O1ii—Ce1—O4v | 94.56 (11) | O5—P1—O5iii | 105.8 (3) |
O2iii—Ce1—O4v | 89.25 (13) | O4vii—P1—Ce1 | 56.30 (14) |
O2—Ce1—O4v | 82.00 (12) | O4vi—P1—Ce1 | 56.30 (14) |
O4iv—Ce1—O4v | 169.05 (16) | O5—P1—Ce1 | 127.12 (15) |
O1i—Ce1—O4vi | 69.77 (12) | O5iii—P1—Ce1 | 127.12 (15) |
O1ii—Ce1—O4vi | 71.56 (13) | O2—P2—O1viii | 119.7 (3) |
O2iii—Ce1—O4vi | 134.71 (13) | O2—P2—O3ix | 107.39 (19) |
O2—Ce1—O4vi | 135.74 (13) | O1viii—P2—O3ix | 111.9 (2) |
O4iv—Ce1—O4vi | 68.42 (12) | O2—P2—O5viii | 108.2 (2) |
O4v—Ce1—O4vi | 122.52 (8) | O1viii—P2—O5viii | 107.4 (2) |
O1i—Ce1—O4vii | 71.56 (13) | O3ix—P2—O5viii | 100.56 (17) |
O1ii—Ce1—O4vii | 69.77 (12) | P2x—O1—Ce1xi | 167.6 (3) |
O2iii—Ce1—O4vii | 135.74 (13) | P2—O2—Ce1 | 146.1 (2) |
O2—Ce1—O4vii | 134.71 (13) | P2xii—O3—P2xiii | 138.8 (3) |
O4iv—Ce1—O4vii | 122.52 (8) | P1xiv—O4—Ce1xv | 148.8 (2) |
O4v—Ce1—O4vii | 68.42 (12) | P1xiv—O4—Ce1xiv | 96.55 (15) |
O4vi—Ce1—O4vii | 54.29 (12) | Ce1xv—O4—Ce1xiv | 110.79 (13) |
O1i—Ce1—P1 | 68.16 (11) | P1—O5—P2x | 139.5 (3) |
O1ii—Ce1—P1 | 68.16 (11) | | |
Symmetry codes: (i) −x+3/2, y+1/2, −z+1/2; (ii) x+1/2, y+1/2, z; (iii) −x+2, y, −z+1/2; (iv) −x+1, −y+1, z−1/2; (v) x+1, −y+1, −z+1; (vi) −x+1, y, −z+1/2; (vii) x+1, y, z; (viii) x, y+1, z; (ix) x, y, z−1; (x) x, y−1, z; (xi) x−1/2, y−1/2, z; (xii) x, −y+2, −z+1; (xiii) x, y, z+1; (xiv) x−1, y, z; (xv) −x+1, −y+1, z+1/2. |