Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270105039041/bc1085sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270105039041/bc1085Isup2.hkl |
Na2CaVO(PO4)2 was synthesized from Na4P2O7, Ca2P2O7 and VO2, as described previously (Chernaya et al., 2004). Single crystals of Ca8.42Na1.16V(PO4)7 were obtained by melting a single-phase powder sample of Na2CaVO(PO4)2 in an argon atmosphere at 1013 K followed by slow cooling (5 K min−1). In addition to the brown crystals used for the present study, green crystals with unit-cell parameters close to those for Ca8.42Na1.16V(PO4)7 were also recovered. A refinement of the Na/Ca ratio in these crystals resulted in almost the same value (1.09/8.46) as for the brown crystals. The difference in colour may be attributed to structural defects or to an inhomogeneous distribution of Na atoms in the crystals.
The atomic positions for the Ca, V, P and O atoms were determined by direct methods. Subsequent difference Fourier syntheses and least-square refinements resulted in the Ca9V(PO4)7 composition, confirming that the structure belongs to the whitlockite type.
The isotropic displacement parameter for atom Ca3 (0.015 Å2) was found to be twice as large as those for atoms Ca1 and Ca2 (0.007 Å2), despite the fact that all three positions have similar O-atom coordination. The larger displacement parameter for atom Ca3 may be indicative of a partial occupancy or of the presence of a lighter atom in this position. Furthermore, a significant residual electron density (about 7.5 e Å−3) was detected near the M4 position. Both discrepancies have been attributed to Na atoms, which were present in the reaction mixture and thus may have entered the structure. A simple introduction of Na cations into the Ca9NaxV(PO4)7 structure should result in the reduction of vanadium. However, it is well known that a very strong reducing agent is required to reduce vanadium below the +3 oxidation state, whereas our synthetic conditions should not allow for that. The insertion of Na into the structure must be accompanied by a decrease in the Ca content in order to keep the +3 oxidation state of vanadium. Thus, we have considered the following two models:
(i) Na randomly occupies the M4 position only, while the M3 position becomes partially occupied by Ca atoms, and the occupancy factors (g) for both cations are related by the equation gNa(M4) = 2[1 – gCa(M3)].
(ii) Na is located in both the M4 and the M3 positions. Then the occupancies should be expressed as gNa(M3) + gCa(M3) = 1 and gNa(M3) = gNa(M4).
Both models were checked carefully. Model (i) resulted in an R value of 0.025, while model (ii) led to an R value of 0.018. This value, however, is close to that (0.019) obtained for the structural model excluding Na atoms. Nevertheless, the similarity of the displacement parameters for the three Ca positions and the lower residual electron density peaks observed in the difference Fourier map indirectly confirm the correctness of our structure solution using model (ii).
During the refinement, the Flack parameter was found to be 0.47 (3). This may indicate that either the structure is centrosymmetric or the crystal is twinned. The only possible space group having particular systematic extinctions is R3c. Indeed, almost all cationic positions are placed in a centrosymmetric manner. However, this is not the case for the position of O atoms. The refinement in the R3c space group gave an R value of 0.30. Therefore, we considered the case of racemic twinning. This resulted in the R value of 0.016 and the BASF parameter of 0.47 (2). Thus, one can conclude that the crystal used in this study is a racemic mixture of two twins with a non-centrosymmetric R3c structure.
Data collection: SMART (Bruker, 1997); cell refinement: SMART; data reduction: SAINT (Bruker, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: JANA2000 (Petricek & Dusek, 2000); software used to prepare material for publication: JANA2000.
Ca8.42Na1.16V(PO4)7 | Dx = 3.139 Mg m−3 |
Mr = 1079.88 | Mo Kα radiation, λ = 0.71069 Å |
Trigonal, R3c | Cell parameters from 9009 reflections |
Hall symbol: R 3 -2"c | θ = 2.5–28.1° |
a = 10.3273 (3) Å | µ = 2.97 mm−1 |
c = 37.098 (2) Å | T = 173 K |
V = 3426.5 (2) Å3 | Irregular, transparent, brown |
Z = 6 | 0.18 × 0.16 × 0.06 mm |
F(000) = 3199 |
Bruker SMART APEX CCD diffractometer | 1818 independent reflections |
Radiation source: fine-focus sealed tube | 1808 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.014 |
0.3° ω exposures scans | θmax = 28.1°, θmin = 2.5° |
Absorption correction: multi-scan ? | h = −13→13 |
Tmin = 0.615, Tmax = 0.841 | k = −13→13 |
9009 measured reflections | l = −49→49 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | w = 1/[σ2(Fo2) + (0.0355P)2 + 2.3095P] where P = (Fo2 + 2Fc2)/3 |
R[F2 > 2σ(F2)] = 0.016 | (Δ/σ)max = 0.001 |
wR(F2) = 0.048 | Δρmax = 0.35 e Å−3 |
S = 1.12 | Δρmin = −0.67 e Å−3 |
1818 reflections | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
143 parameters | Extinction coefficient: 0.00038 (4) |
2 restraints | Absolute structure: Flack (1983), 875 Friedel pairs |
Primary atom site location: structure-invariant direct methods | Absolute structure parameter: 0.0 (3) |
Ca8.42Na1.16V(PO4)7 | Z = 6 |
Mr = 1079.88 | Mo Kα radiation |
Trigonal, R3c | µ = 2.97 mm−1 |
a = 10.3273 (3) Å | T = 173 K |
c = 37.098 (2) Å | 0.18 × 0.16 × 0.06 mm |
V = 3426.5 (2) Å3 |
Bruker SMART APEX CCD diffractometer | 1818 independent reflections |
Absorption correction: multi-scan ? | 1808 reflections with I > 2σ(I) |
Tmin = 0.615, Tmax = 0.841 | Rint = 0.014 |
9009 measured reflections |
R[F2 > 2σ(F2)] = 0.016 | 2 restraints |
wR(F2) = 0.048 | Δρmax = 0.35 e Å−3 |
S = 1.12 | Δρmin = −0.67 e Å−3 |
1818 reflections | Absolute structure: Flack (1983), 875 Friedel pairs |
143 parameters | Absolute structure parameter: 0.0 (3) |
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. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
V | 0.3333 | 0.6667 | 0.435576 (17) | 0.00602 (11) | |
Ca1 | 0.47745 (4) | 0.94303 (4) | 0.366928 (11) | 0.00863 (10) | |
Ca2 | 0.20426 (4) | 0.82509 (4) | 0.499885 (10) | 0.00806 (10) | |
Ca3 | 0.79266 (4) | 0.60531 (5) | 0.426576 (13) | 0.00783 (14) | 0.806 (2) |
P1 | 0.6667 | 0.3333 | 0.36911 (2) | 0.00679 (17) | |
P2 | 0.48571 (6) | 0.47541 (5) | 0.465697 (12) | 0.00599 (11) | |
P3 | 0.17400 (6) | 0.86029 (6) | 0.403712 (12) | 0.00643 (11) | |
Na1 | 0.0000 | 0.0000 | 0.45676 (8) | 0.0116 (8) | 0.582 (6) |
Na2 | 0.79266 (4) | 0.60531 (5) | 0.426576 (13) | 0.00783 (14) | 0.194 |
O1 | 0.6667 | 0.3333 | 0.41030 (7) | 0.0115 (5) | |
O2 | 0.42872 (14) | 0.83736 (18) | 0.47201 (4) | 0.0096 (3) | |
O3 | 0.51579 (14) | 0.47258 (14) | 0.42569 (4) | 0.0087 (3) | |
O4 | 0.27556 (15) | 0.99779 (14) | 0.38046 (3) | 0.0085 (3) | |
O5 | 0.24821 (14) | 0.75839 (14) | 0.40139 (4) | 0.0103 (3) | |
O6 | 0.01562 (15) | 0.76711 (16) | 0.38913 (3) | 0.0120 (3) | |
O7 | 0.63333 (16) | 0.55003 (16) | 0.48613 (4) | 0.0120 (3) | |
O8 | 0.52275 (14) | 0.32709 (17) | 0.35553 (4) | 0.0140 (3) | |
O9 | 0.17915 (16) | 0.91481 (17) | 0.44209 (4) | 0.0138 (3) | |
O10 | 0.37735 (14) | 0.31579 (15) | 0.47842 (4) | 0.0106 (3) |
U11 | U22 | U33 | U12 | U13 | U23 | |
V | 0.00558 (15) | 0.00558 (15) | 0.0069 (2) | 0.00279 (8) | 0.000 | 0.000 |
Ca1 | 0.00882 (18) | 0.00833 (19) | 0.0090 (2) | 0.00449 (14) | 0.00078 (13) | 0.00014 (14) |
Ca2 | 0.00893 (17) | 0.00759 (18) | 0.00776 (18) | 0.00422 (15) | 0.00085 (15) | −0.00043 (15) |
Ca3 | 0.0059 (2) | 0.0109 (2) | 0.0074 (2) | 0.00476 (16) | −0.00024 (14) | 0.00287 (14) |
P1 | 0.0055 (2) | 0.0055 (2) | 0.0094 (4) | 0.00274 (12) | 0.000 | 0.000 |
P2 | 0.0062 (2) | 0.0061 (2) | 0.0064 (2) | 0.00367 (16) | 0.0001 (2) | 0.00009 (19) |
P3 | 0.0060 (2) | 0.0063 (2) | 0.0072 (2) | 0.00322 (17) | 0.00003 (19) | 0.00021 (18) |
Na1 | 0.0122 (10) | 0.0122 (10) | 0.0105 (15) | 0.0061 (5) | 0.000 | 0.000 |
Na2 | 0.0059 (2) | 0.0109 (2) | 0.0074 (2) | 0.00476 (16) | −0.00024 (14) | 0.00287 (14) |
O1 | 0.0124 (8) | 0.0124 (8) | 0.0096 (12) | 0.0062 (4) | 0.000 | 0.000 |
O2 | 0.0070 (6) | 0.0070 (6) | 0.0137 (7) | 0.0028 (5) | 0.0006 (4) | 0.0019 (5) |
O3 | 0.0091 (6) | 0.0094 (6) | 0.0072 (7) | 0.0043 (5) | 0.0002 (4) | −0.0001 (5) |
O4 | 0.0103 (6) | 0.0089 (6) | 0.0071 (5) | 0.0054 (5) | 0.0008 (4) | 0.0017 (4) |
O5 | 0.0086 (6) | 0.0071 (6) | 0.0162 (7) | 0.0048 (5) | 0.0001 (4) | −0.0004 (4) |
O6 | 0.0066 (6) | 0.0143 (7) | 0.0128 (6) | 0.0033 (5) | −0.0022 (5) | 0.0013 (5) |
O7 | 0.0091 (7) | 0.0147 (7) | 0.0106 (6) | 0.0048 (5) | −0.0031 (5) | −0.0008 (5) |
O8 | 0.0091 (6) | 0.0129 (6) | 0.0214 (6) | 0.0066 (6) | −0.0046 (5) | −0.0049 (5) |
O9 | 0.0145 (7) | 0.0162 (7) | 0.0084 (6) | 0.0059 (6) | 0.0004 (5) | −0.0006 (5) |
O10 | 0.0126 (6) | 0.0080 (6) | 0.0105 (6) | 0.0045 (5) | 0.0018 (5) | 0.0001 (4) |
V—O5 | 2.0276 (16) | P2—O7 | 1.5224 (15) |
V—O5i | 2.0276 (16) | P2—O10 | 1.5323 (14) |
V—O5ii | 2.0276 (16) | P2—O2ii | 1.5674 (16) |
V—O2 | 2.0416 (16) | P2—Na2xiii | 3.0072 (6) |
V—O2i | 2.0416 (16) | P2—Ca3xiii | 3.0072 (6) |
V—O2ii | 2.0416 (16) | P2—Ca2i | 3.1158 (7) |
V—Ca2 | 3.5109 (6) | P2—Ca2ii | 3.1438 (6) |
V—Ca2ii | 3.5109 (6) | P3—O9 | 1.5220 (15) |
V—Ca2i | 3.5109 (6) | P3—O6 | 1.5233 (14) |
V—Ca1i | 3.5495 (6) | P3—O4 | 1.5399 (14) |
V—Ca1 | 3.5495 (6) | P3—O5 | 1.5838 (16) |
V—Ca1ii | 3.5495 (6) | P3—Na2i | 3.1023 (6) |
Ca1—O7iii | 2.3131 (14) | P3—Ca3i | 3.1023 (6) |
Ca1—O3i | 2.3569 (16) | P3—Ca1i | 3.2529 (6) |
Ca1—O8i | 2.4071 (15) | P3—Na1vi | 3.4317 (18) |
Ca1—O10iv | 2.4681 (14) | Na1—O9xvi | 2.4741 (16) |
Ca1—O4 | 2.4694 (13) | Na1—O9xv | 2.4741 (16) |
Ca1—O5ii | 2.5135 (14) | Na1—O9i | 2.4741 (16) |
Ca1—O5 | 2.5222 (14) | Na1—O8xvii | 2.830 (3) |
Ca1—O6ii | 2.7679 (15) | Na1—O8xviii | 2.830 (3) |
Ca1—P3 | 3.1201 (6) | Na1—O8xix | 2.830 (3) |
Ca1—P3ii | 3.2529 (6) | Na1—P1xvii | 2.931 (3) |
Ca1—Ca2v | 3.4887 (5) | Na1—P3xvi | 3.4317 (18) |
Ca1—P1vi | 3.4922 (4) | Na1—P3xv | 3.4316 (18) |
Ca2—O8vii | 2.3215 (14) | Na1—P3i | 3.4316 (18) |
Ca2—O4viii | 2.3735 (13) | Na1—Ca3xx | 3.7048 (10) |
Ca2—O9 | 2.4008 (15) | Na1—Na2xx | 3.7048 (10) |
Ca2—O6ix | 2.4515 (13) | O1—Na2xi | 2.5084 (8) |
Ca2—O2i | 2.4582 (13) | O1—Ca3xi | 2.5084 (8) |
Ca2—O2 | 2.4830 (13) | O1—Ca3xiii | 2.5084 (8) |
Ca2—O10ii | 2.6080 (14) | O1—Na2xiii | 2.5084 (8) |
Ca2—O7i | 2.6540 (15) | O2—P2i | 1.5674 (16) |
Ca2—P2ii | 3.1158 (7) | O2—Ca2ii | 2.4582 (13) |
Ca2—P2i | 3.1438 (6) | O3—Ca1ii | 2.3569 (16) |
Ca2—Ca1x | 3.4887 (5) | O3—Na2xiii | 2.5608 (13) |
Ca3—O10xi | 2.3932 (14) | O3—Ca3xiii | 2.5608 (13) |
Ca3—O4ii | 2.4217 (13) | O4—Ca2xxi | 2.3735 (13) |
Ca3—O3 | 2.4772 (13) | O4—Na2i | 2.4217 (14) |
Ca3—O6xii | 2.4852 (14) | O4—Ca3i | 2.4217 (14) |
Ca3—O1 | 2.5084 (8) | O5—Ca1i | 2.5135 (14) |
Ca3—O3xi | 2.5608 (13) | O6—Ca2xxii | 2.4515 (13) |
Ca3—O9ii | 2.6349 (16) | O6—Na2xxiii | 2.4852 (14) |
Ca3—O7 | 2.6411 (15) | O6—Ca3xxiii | 2.4852 (14) |
Ca3—O8xi | 2.9784 (16) | O6—Ca1i | 2.7679 (15) |
Ca3—P2xi | 3.0073 (6) | O7—Ca1xix | 2.3131 (14) |
Ca3—P3ii | 3.1023 (6) | O7—Ca2ii | 2.6540 (14) |
Ca3—P2 | 3.1148 (6) | O8—Ca2xxiv | 2.3216 (14) |
P1—O1 | 1.528 (3) | O8—Ca1ii | 2.4071 (14) |
P1—O8xiii | 1.5399 (12) | O8—Na1xiv | 2.830 (3) |
P1—O8xi | 1.5399 (13) | O8—Na2xiii | 2.9784 (16) |
P1—O8 | 1.5399 (12) | O8—Ca3xiii | 2.9784 (16) |
P1—Na1xiv | 2.931 (3) | O9—Na1vi | 2.4741 (16) |
P1—Na2xi | 3.2361 (7) | O9—Na2i | 2.6350 (16) |
P1—Ca3xi | 3.2361 (7) | O9—Ca3i | 2.6350 (16) |
P1—Ca3xiii | 3.2361 (7) | O10—Na2xiii | 2.3932 (14) |
P1—Na2xiii | 3.2361 (7) | O10—Ca3xiii | 2.3932 (14) |
P1—Ca1xv | 3.4922 (4) | O10—Ca1xxv | 2.4681 (14) |
P2—O3 | 1.5196 (16) | O10—Ca2i | 2.6080 (13) |
O5—V—O5i | 85.02 (7) | O8xi—P1—O8 | 109.83 (6) |
O5—V—O5ii | 85.02 (7) | O1—P1—Na1xiv | 180.0 |
O5i—V—O5ii | 85.02 (7) | O8xiii—P1—Na1xiv | 70.89 (6) |
O5—V—O2 | 98.36 (6) | O8xi—P1—Na1xiv | 70.89 (6) |
O5i—V—O2 | 176.59 (6) | O8—P1—Na1xiv | 70.89 (6) |
O5ii—V—O2 | 95.66 (5) | O1—P1—Na2xi | 48.795 (14) |
O5—V—O2i | 95.66 (5) | O8xiii—P1—Na2xi | 66.51 (6) |
O5i—V—O2i | 98.36 (6) | O8xi—P1—Na2xi | 102.29 (6) |
O5ii—V—O2i | 176.59 (7) | O8—P1—Na2xi | 146.38 (7) |
O2—V—O2i | 80.94 (7) | Na1xiv—P1—Na2xi | 131.206 (14) |
O5—V—O2ii | 176.59 (6) | O1—P1—Ca3xi | 48.795 (14) |
O5i—V—O2ii | 95.66 (5) | O8xiii—P1—Ca3xi | 66.51 (6) |
O5ii—V—O2ii | 98.36 (6) | O8xi—P1—Ca3xi | 102.29 (6) |
O2—V—O2ii | 80.94 (7) | O8—P1—Ca3xi | 146.38 (7) |
O2i—V—O2ii | 80.94 (7) | Na1xiv—P1—Ca3xi | 131.206 (14) |
O5—V—Ca2 | 81.54 (4) | O1—P1—Ca3 | 48.795 (14) |
O5i—V—Ca2 | 136.85 (4) | O8xiii—P1—Ca3 | 146.38 (6) |
O5ii—V—Ca2 | 133.83 (4) | O8xi—P1—Ca3 | 66.51 (6) |
O2—V—Ca2 | 43.90 (4) | O8—P1—Ca3 | 102.29 (6) |
O2i—V—Ca2 | 43.19 (4) | Na1xiv—P1—Ca3 | 131.205 (14) |
O2ii—V—Ca2 | 95.74 (5) | Na2xi—P1—Ca3 | 81.32 (2) |
O5—V—Ca2ii | 136.85 (4) | Ca3xi—P1—Ca3 | 81.32 (2) |
O5i—V—Ca2ii | 133.83 (4) | O1—P1—Ca3xiii | 48.795 (14) |
O5ii—V—Ca2ii | 81.54 (4) | O8xiii—P1—Ca3xiii | 102.29 (6) |
O2—V—Ca2ii | 43.19 (4) | O8xi—P1—Ca3xiii | 146.38 (6) |
O2i—V—Ca2ii | 95.74 (5) | O8—P1—Ca3xiii | 66.51 (6) |
O2ii—V—Ca2ii | 43.90 (4) | Na1xiv—P1—Ca3xiii | 131.205 (14) |
Ca2—V—Ca2ii | 78.893 (15) | Na2xi—P1—Ca3xiii | 81.32 (2) |
O5—V—Ca2i | 133.83 (4) | Ca3xi—P1—Ca3xiii | 81.32 (2) |
O5i—V—Ca2i | 81.54 (4) | Ca3—P1—Ca3xiii | 81.32 (2) |
O5ii—V—Ca2i | 136.85 (4) | O1—P1—Na2xiii | 48.795 (14) |
O2—V—Ca2i | 95.74 (5) | O8xiii—P1—Na2xiii | 102.29 (6) |
O2i—V—Ca2i | 43.90 (4) | O8xi—P1—Na2xiii | 146.38 (6) |
O2ii—V—Ca2i | 43.19 (4) | O8—P1—Na2xiii | 66.51 (6) |
Ca2—V—Ca2i | 78.893 (15) | Na1xiv—P1—Na2xiii | 131.205 (14) |
Ca2ii—V—Ca2i | 78.893 (15) | Na2xi—P1—Na2xiii | 81.32 (2) |
O5—V—Ca1i | 43.78 (4) | Ca3xi—P1—Na2xiii | 81.32 (2) |
O5i—V—Ca1i | 44.03 (4) | O1—P1—Ca1xv | 91.329 (16) |
O5ii—V—Ca1i | 95.44 (5) | O8xi—P1—Ca1xv | 145.10 (6) |
O2—V—Ca1i | 139.05 (4) | O8—P1—Ca1xv | 88.44 (6) |
O2i—V—Ca1i | 87.33 (4) | Na1xiv—P1—Ca1xv | 88.671 (16) |
O2ii—V—Ca1i | 135.75 (4) | Na2xi—P1—Ca1xv | 69.849 (11) |
Ca2—V—Ca1i | 104.315 (10) | Ca3xi—P1—Ca1xv | 69.849 (11) |
Ca2ii—V—Ca1i | 176.655 (16) | Ca3—P1—Ca1xv | 140.10 (3) |
Ca2i—V—Ca1i | 102.539 (9) | Ca3xiii—P1—Ca1xv | 67.861 (11) |
O5—V—Ca1 | 44.03 (4) | Na2xiii—P1—Ca1xv | 67.861 (11) |
O5i—V—Ca1 | 95.44 (5) | O3—P2—O7 | 109.48 (8) |
O5ii—V—Ca1 | 43.78 (4) | O3—P2—O10 | 109.05 (7) |
O2—V—Ca1 | 87.33 (4) | O7—P2—O10 | 113.52 (8) |
O2i—V—Ca1 | 135.75 (4) | O3—P2—O2ii | 109.35 (8) |
O2ii—V—Ca1 | 139.05 (4) | O7—P2—O2ii | 107.59 (8) |
Ca2—V—Ca1 | 102.539 (9) | O10—P2—O2ii | 107.77 (7) |
Ca2ii—V—Ca1 | 104.315 (10) | O3—P2—Na2xiii | 58.36 (5) |
Ca2i—V—Ca1 | 176.655 (16) | O7—P2—Na2xiii | 118.66 (6) |
Ca1i—V—Ca1 | 74.207 (15) | O10—P2—Na2xiii | 52.08 (5) |
O5—V—Ca1ii | 95.44 (5) | O2ii—P2—Na2xiii | 133.69 (6) |
O5i—V—Ca1ii | 43.78 (4) | O3—P2—Ca3xiii | 58.36 (5) |
O5ii—V—Ca1ii | 44.03 (4) | O7—P2—Ca3xiii | 118.66 (6) |
O2—V—Ca1ii | 135.75 (4) | O10—P2—Ca3xiii | 52.08 (5) |
O2i—V—Ca1ii | 139.05 (4) | O2ii—P2—Ca3xiii | 133.69 (6) |
O2ii—V—Ca1ii | 87.33 (4) | O3—P2—Ca3 | 51.64 (5) |
Ca2—V—Ca1ii | 176.655 (16) | O7—P2—Ca3 | 57.87 (6) |
Ca2ii—V—Ca1ii | 102.539 (9) | O10—P2—Ca3 | 130.20 (6) |
Ca2i—V—Ca1ii | 104.315 (10) | O2ii—P2—Ca3 | 121.77 (5) |
Ca1i—V—Ca1ii | 74.206 (15) | Na2xiii—P2—Ca3 | 87.05 (2) |
Ca1—V—Ca1ii | 74.207 (15) | Ca3xiii—P2—Ca3 | 87.05 (2) |
O7iii—Ca1—O3i | 142.38 (5) | O3—P2—Ca2i | 125.40 (6) |
O7iii—Ca1—O8i | 84.43 (5) | O7—P2—Ca2i | 124.74 (6) |
O3i—Ca1—O8i | 78.81 (5) | O10—P2—Ca2i | 56.61 (5) |
O7iii—Ca1—O10iv | 73.56 (5) | O2ii—P2—Ca2i | 51.19 (5) |
O3i—Ca1—O10iv | 138.50 (5) | Na2xiii—P2—Ca2i | 96.792 (17) |
O8i—Ca1—O10iv | 88.59 (5) | Ca3xiii—P2—Ca2i | 96.792 (17) |
O7iii—Ca1—O4 | 141.41 (5) | Ca3—P2—Ca2i | 172.42 (2) |
O3i—Ca1—O4 | 74.70 (4) | O3—P2—Ca2ii | 115.27 (5) |
O8i—Ca1—O4 | 97.70 (5) | O7—P2—Ca2ii | 57.40 (6) |
O10iv—Ca1—O4 | 68.00 (4) | O10—P2—Ca2ii | 135.16 (6) |
O7iii—Ca1—O5ii | 84.87 (5) | O2ii—P2—Ca2ii | 51.20 (5) |
O3i—Ca1—O5ii | 77.79 (5) | Na2xiii—P2—Ca2ii | 172.05 (2) |
O8i—Ca1—O5ii | 124.87 (5) | Ca3xiii—P2—Ca2ii | 172.05 (2) |
O10iv—Ca1—O5ii | 138.37 (5) | Ca3—P2—Ca2ii | 85.072 (17) |
O4—Ca1—O5ii | 122.49 (5) | Ca2i—P2—Ca2ii | 90.91 (2) |
O7iii—Ca1—O5 | 125.07 (5) | O9—P3—O6 | 113.19 (8) |
O3i—Ca1—O5 | 77.27 (5) | O9—P3—O4 | 107.53 (8) |
O8i—Ca1—O5 | 150.46 (5) | O6—P3—O4 | 113.87 (8) |
O10iv—Ca1—O5 | 97.99 (5) | O9—P3—O5 | 110.95 (8) |
O4—Ca1—O5 | 59.29 (5) | O6—P3—O5 | 106.52 (8) |
O5ii—Ca1—O5 | 65.94 (7) | O4—P3—O5 | 104.45 (7) |
O7iii—Ca1—O6ii | 71.60 (4) | O9—P3—Na2i | 58.05 (6) |
O3i—Ca1—O6ii | 71.00 (4) | O6—P3—Na2i | 139.22 (6) |
O8i—Ca1—O6ii | 69.29 (4) | O4—P3—Na2i | 50.08 (5) |
O10iv—Ca1—O6ii | 140.07 (5) | O5—P3—Na2i | 113.71 (5) |
O4—Ca1—O6ii | 145.03 (5) | O9—P3—Ca3i | 58.05 (6) |
O5ii—Ca1—O6ii | 56.01 (5) | O6—P3—Ca3i | 139.22 (6) |
O5—Ca1—O6ii | 117.82 (5) | O4—P3—Ca3i | 50.08 (5) |
O7iii—Ca1—P3 | 143.51 (4) | O5—P3—Ca3i | 113.71 (5) |
O3i—Ca1—P3 | 71.65 (3) | O9—P3—Ca1 | 117.60 (6) |
O8i—Ca1—P3 | 123.84 (4) | O6—P3—Ca1 | 129.19 (6) |
O10iv—Ca1—P3 | 83.74 (3) | O4—P3—Ca1 | 51.30 (5) |
O4—Ca1—P3 | 29.12 (3) | O5—P3—Ca1 | 53.48 (5) |
O5ii—Ca1—P3 | 94.22 (4) | Na2i—P3—Ca1 | 74.389 (15) |
O5—Ca1—P3 | 30.31 (4) | Ca3i—P3—Ca1 | 74.389 (15) |
O6ii—Ca1—P3 | 136.18 (3) | O9—P3—Ca1i | 134.53 (6) |
O7iii—Ca1—P3ii | 74.37 (4) | O6—P3—Ca1i | 58.08 (6) |
O3i—Ca1—P3ii | 74.62 (3) | O4—P3—Ca1i | 116.64 (5) |
O8i—Ca1—P3ii | 97.12 (4) | O5—P3—Ca1i | 48.91 (5) |
O10iv—Ca1—P3ii | 146.68 (4) | Na2i—P3—Ca1i | 158.71 (2) |
O4—Ca1—P3ii | 142.41 (4) | Ca3i—P3—Ca1i | 158.71 (2) |
O5ii—Ca1—P3ii | 28.35 (4) | Ca1—P3—Ca1i | 84.412 (19) |
O5—Ca1—P3ii | 93.01 (4) | O6—P3—Na1vi | 81.18 (6) |
O6ii—Ca1—P3ii | 27.85 (3) | O4—P3—Na1vi | 101.07 (6) |
P3—Ca1—P3ii | 118.46 (2) | O5—P3—Na1vi | 147.09 (7) |
O7iii—Ca1—Ca2v | 49.52 (4) | Na2i—P3—Na1vi | 68.871 (14) |
O3i—Ca1—Ca2v | 98.66 (3) | Ca3i—P3—Na1vi | 68.871 (14) |
O8i—Ca1—Ca2v | 41.52 (3) | Ca1—P3—Na1vi | 143.230 (18) |
O10iv—Ca1—Ca2v | 97.30 (3) | Ca1i—P3—Na1vi | 132.357 (19) |
O4—Ca1—Ca2v | 138.40 (3) | O9xvi—Na1—O9xv | 115.30 (5) |
O5ii—Ca1—Ca2v | 94.80 (4) | O9xvi—Na1—O9i | 115.30 (5) |
O5—Ca1—Ca2v | 160.72 (4) | O9xv—Na1—O9i | 115.30 (5) |
O6ii—Ca1—Ca2v | 44.30 (3) | O9xvi—Na1—O8xvii | 107.96 (8) |
P3—Ca1—Ca2v | 165.023 (17) | O9xv—Na1—O8xvii | 123.42 (9) |
P3ii—Ca1—Ca2v | 67.831 (14) | O9i—Na1—O8xvii | 72.97 (6) |
O7iii—Ca1—P1vi | 105.01 (4) | O9xvi—Na1—O8xviii | 72.97 (6) |
O3i—Ca1—P1vi | 66.33 (4) | O9xv—Na1—O8xviii | 107.96 (8) |
O8i—Ca1—P1vi | 21.72 (3) | O9i—Na1—O8xviii | 123.42 (9) |
O10iv—Ca1—P1vi | 87.85 (3) | O8xvii—Na1—O8xviii | 52.88 (6) |
O4—Ca1—P1vi | 77.30 (3) | O9xvi—Na1—O8xix | 123.42 (9) |
O5ii—Ca1—P1vi | 132.66 (4) | O9xv—Na1—O8xix | 72.97 (6) |
O5—Ca1—P1vi | 129.26 (4) | O9i—Na1—O8xix | 107.96 (8) |
O6ii—Ca1—P1vi | 82.88 (3) | O8xvii—Na1—O8xix | 52.88 (6) |
P3—Ca1—P1vi | 102.222 (15) | O8xviii—Na1—O8xix | 52.88 (6) |
P3ii—Ca1—P1vi | 109.076 (16) | O9xvi—Na1—P1xvii | 102.71 (8) |
Ca2v—Ca1—P1vi | 62.977 (11) | O9xv—Na1—P1xvii | 102.71 (8) |
O8vii—Ca2—O4viii | 86.01 (5) | O9i—Na1—P1xvii | 102.71 (8) |
O8vii—Ca2—O9 | 84.21 (5) | O8xvii—Na1—P1xvii | 30.94 (4) |
O4viii—Ca2—O9 | 140.55 (5) | O8xviii—Na1—P1xvii | 30.94 (4) |
O8vii—Ca2—O6ix | 76.51 (5) | O8xix—Na1—P1xvii | 30.94 (4) |
O4viii—Ca2—O6ix | 72.49 (5) | O9xvi—Na1—P3xvi | 23.42 (4) |
O9—Ca2—O6ix | 140.54 (5) | O9xv—Na1—P3xvi | 111.45 (8) |
O8vii—Ca2—O2i | 156.17 (6) | O9i—Na1—P3xvi | 99.99 (7) |
O4viii—Ca2—O2i | 83.68 (5) | O8xvii—Na1—P3xvi | 122.31 (4) |
O9—Ca2—O2i | 90.21 (5) | O8xviii—Na1—P3xvi | 96.18 (3) |
O6ix—Ca2—O2i | 120.18 (5) | O8xix—Na1—P3xvi | 146.45 (6) |
O8vii—Ca2—O2 | 136.83 (5) | P1xvii—Na1—P3xvi | 124.99 (4) |
O4viii—Ca2—O2 | 127.18 (5) | O9xvi—Na1—P3xv | 99.99 (7) |
O9—Ca2—O2 | 83.49 (5) | O9xv—Na1—P3xv | 23.42 (4) |
O6ix—Ca2—O2 | 87.51 (5) | O9i—Na1—P3xv | 111.45 (8) |
O2i—Ca2—O2 | 64.87 (7) | O8xvii—Na1—P3xv | 146.45 (6) |
O8vii—Ca2—O10ii | 97.03 (5) | O8xviii—Na1—P3xv | 122.31 (4) |
O4viii—Ca2—O10ii | 67.13 (4) | O8xix—Na1—P3xv | 96.18 (3) |
O9—Ca2—O10ii | 76.30 (5) | P1xvii—Na1—P3xv | 124.99 (4) |
O6ix—Ca2—O10ii | 139.48 (5) | P3xvi—Na1—P3xv | 90.38 (6) |
O2i—Ca2—O10ii | 59.15 (5) | O9xvi—Na1—P3i | 111.45 (8) |
O2—Ca2—O10ii | 119.69 (5) | O9xv—Na1—P3i | 99.99 (7) |
O8vii—Ca2—O7i | 78.92 (5) | O9i—Na1—P3i | 23.42 (4) |
O4viii—Ca2—O7i | 143.48 (5) | O8xvii—Na1—P3i | 96.18 (3) |
O9—Ca2—O7i | 70.98 (5) | O8xviii—Na1—P3i | 146.45 (6) |
O6ix—Ca2—O7i | 71.71 (4) | O8xix—Na1—P3i | 122.31 (4) |
O2i—Ca2—O7i | 121.04 (5) | P1xvii—Na1—P3i | 124.99 (4) |
O2—Ca2—O7i | 57.96 (5) | P3xvi—Na1—P3i | 90.38 (6) |
O10ii—Ca2—O7i | 147.26 (5) | P3xv—Na1—P3i | 90.38 (6) |
O8vii—Ca2—P2ii | 126.38 (4) | O9xvi—Na1—Ca3xx | 45.26 (4) |
O4viii—Ca2—P2ii | 72.68 (3) | O9xv—Na1—Ca3xx | 70.48 (4) |
O9—Ca2—P2ii | 82.85 (4) | O9i—Na1—Ca3xx | 146.99 (11) |
O6ix—Ca2—P2ii | 136.05 (4) | O8xvii—Na1—Ca3xx | 133.31 (7) |
O2i—Ca2—P2ii | 29.79 (4) | O8xviii—Na1—Ca3xx | 80.62 (3) |
O2—Ca2—P2ii | 92.75 (4) | O8xix—Na1—Ca3xx | 104.76 (4) |
O10ii—Ca2—P2ii | 29.38 (3) | P1xvii—Na1—Ca3xx | 107.59 (4) |
O7i—Ca2—P2ii | 141.90 (3) | P3xvi—Na1—Ca3xx | 51.36 (2) |
O8vii—Ca2—P2i | 107.68 (4) | P3xv—Na1—Ca3xx | 60.01 (3) |
O4viii—Ca2—P2i | 147.07 (4) | P3i—Na1—Ca3xx | 127.18 (9) |
O9—Ca2—P2i | 71.86 (4) | O9xvi—Na1—Na2xx | 45.26 (4) |
O6ix—Ca2—P2i | 81.61 (4) | O9xv—Na1—Na2xx | 70.48 (4) |
O2i—Ca2—P2i | 92.40 (4) | O9i—Na1—Na2xx | 146.99 (11) |
O2—Ca2—P2i | 29.47 (4) | O8xvii—Na1—Na2xx | 133.31 (7) |
O10ii—Ca2—P2i | 136.90 (3) | O8xviii—Na1—Na2xx | 80.62 (3) |
O7i—Ca2—P2i | 28.90 (3) | O8xix—Na1—Na2xx | 104.76 (4) |
P2ii—Ca2—P2i | 116.90 (2) | P1xvii—Na1—Na2xx | 107.59 (4) |
O8vii—Ca2—Ca1x | 43.41 (4) | P3xvi—Na1—Na2xx | 51.36 (2) |
O4viii—Ca2—Ca1x | 107.69 (3) | P3xv—Na1—Na2xx | 60.01 (3) |
O9—Ca2—Ca1x | 90.67 (4) | P3i—Na1—Na2xx | 127.18 (9) |
O6ix—Ca2—Ca1x | 52.05 (4) | Ca3xx—Na1—Na2xx | 0.000 (14) |
O2i—Ca2—Ca1x | 160.19 (4) | P1—O1—Na2xi | 103.93 (6) |
O2—Ca2—Ca1x | 95.58 (4) | P1—O1—Ca3xi | 103.93 (6) |
O10ii—Ca2—Ca1x | 139.92 (3) | P1—O1—Ca3 | 103.93 (6) |
O7i—Ca2—Ca1x | 41.52 (3) | Na2xi—O1—Ca3 | 114.40 (5) |
P2ii—Ca2—Ca1x | 168.808 (18) | Ca3xi—O1—Ca3 | 114.40 (5) |
P2i—Ca2—Ca1x | 69.141 (13) | P1—O1—Ca3xiii | 103.93 (6) |
O8vii—Ca2—V | 156.31 (4) | Na2xi—O1—Ca3xiii | 114.40 (5) |
O4viii—Ca2—V | 116.08 (4) | Ca3xi—O1—Ca3xiii | 114.40 (5) |
O9—Ca2—V | 73.28 (4) | Ca3—O1—Ca3xiii | 114.40 (5) |
O6ix—Ca2—V | 116.76 (4) | P1—O1—Na2xiii | 103.93 (6) |
O2i—Ca2—V | 34.64 (4) | Na2xi—O1—Na2xiii | 114.40 (5) |
O2—Ca2—V | 34.76 (4) | P2i—O2—V | 129.95 (9) |
O10ii—Ca2—V | 84.93 (3) | P2i—O2—Ca2ii | 99.03 (6) |
O7i—Ca2—V | 86.70 (3) | V—O2—Ca2ii | 102.16 (6) |
P2ii—Ca2—V | 58.902 (11) | P2i—O2—Ca2 | 99.33 (7) |
P2i—Ca2—V | 58.679 (12) | V—O2—Ca2 | 101.34 (5) |
Ca1x—Ca2—V | 127.811 (13) | Ca2ii—O2—Ca2 | 129.08 (6) |
O10xi—Ca3—O4ii | 150.13 (5) | P2—O3—Ca1ii | 146.06 (9) |
O10xi—Ca3—O3 | 124.12 (5) | P2—O3—Ca3 | 99.61 (7) |
O4ii—Ca3—O3 | 73.44 (5) | Ca1ii—O3—Ca3 | 102.15 (5) |
O10xi—Ca3—O6xii | 93.57 (4) | P2—O3—Na2xiii | 91.30 (6) |
O4ii—Ca3—O6xii | 71.10 (5) | Ca1ii—O3—Na2xiii | 103.26 (5) |
O3—Ca3—O6xii | 142.16 (5) | Ca3—O3—Na2xiii | 113.65 (6) |
O10xi—Ca3—O1 | 103.41 (6) | P2—O3—Ca3xiii | 91.30 (6) |
O4ii—Ca3—O1 | 106.22 (6) | Ca1ii—O3—Ca3xiii | 103.26 (5) |
O3—Ca3—O1 | 64.42 (4) | Ca3—O3—Ca3xiii | 113.65 (6) |
O6xii—Ca3—O1 | 113.94 (6) | P3—O4—Ca2xxi | 146.26 (8) |
O10xi—Ca3—O3xi | 60.11 (5) | P3—O4—Na2i | 100.73 (7) |
O4ii—Ca3—O3xi | 132.79 (5) | Ca2xxi—O4—Na2i | 97.40 (5) |
O3—Ca3—O3xi | 126.32 (6) | P3—O4—Ca3i | 100.73 (7) |
O6xii—Ca3—O3xi | 72.80 (5) | Ca2xxi—O4—Ca3i | 97.40 (5) |
O1—Ca3—O3xi | 63.22 (3) | P3—O4—Ca1 | 99.58 (6) |
O10xi—Ca3—O9ii | 99.16 (5) | Ca2xxi—O4—Ca1 | 104.79 (5) |
O4ii—Ca3—O9ii | 58.29 (4) | Na2i—O4—Ca1 | 100.54 (5) |
O3—Ca3—O9ii | 77.69 (5) | Ca3i—O4—Ca1 | 100.54 (5) |
O6xii—Ca3—O9ii | 94.43 (5) | P3—O5—V | 138.02 (9) |
O1—Ca3—O9ii | 142.05 (4) | P3—O5—Ca1i | 102.74 (7) |
O3xi—Ca3—O9ii | 153.82 (5) | V—O5—Ca1i | 102.30 (6) |
O10xi—Ca3—O7 | 69.18 (5) | P3—O5—Ca1 | 96.22 (6) |
O4ii—Ca3—O7 | 112.82 (5) | V—O5—Ca1 | 102.00 (6) |
O3—Ca3—O7 | 57.96 (5) | Ca1i—O5—Ca1 | 116.52 (6) |
O6xii—Ca3—O7 | 151.72 (5) | P3—O6—Ca2xxii | 141.66 (8) |
O1—Ca3—O7 | 92.35 (6) | P3—O6—Na2xxiii | 124.57 (7) |
O3xi—Ca3—O7 | 113.46 (5) | Ca2xxii—O6—Na2xxiii | 93.73 (5) |
O9ii—Ca3—O7 | 67.77 (4) | P3—O6—Ca3xxiii | 124.57 (7) |
O10xi—Ca3—O8xi | 125.51 (5) | Ca2xxii—O6—Ca3xxiii | 93.73 (5) |
O4ii—Ca3—O8xi | 71.91 (5) | P3—O6—Ca1i | 94.08 (6) |
O3—Ca3—O8xi | 91.97 (4) | Ca2xxii—O6—Ca1i | 83.66 (4) |
O6xii—Ca3—O8xi | 64.80 (4) | Na2xxiii—O6—Ca1i | 94.35 (5) |
O1—Ca3—O8xi | 53.36 (6) | Ca3xxiii—O6—Ca1i | 94.35 (5) |
O3xi—Ca3—O8xi | 65.68 (5) | P2—O7—Ca1xix | 159.02 (9) |
O9ii—Ca3—O8xi | 130.10 (5) | P2—O7—Ca3 | 92.91 (6) |
O7—Ca3—O8xi | 143.47 (4) | Ca1xix—O7—Ca3 | 106.35 (5) |
O10xi—Ca3—P2xi | 30.34 (3) | P2—O7—Ca2ii | 93.70 (6) |
O4ii—Ca3—P2xi | 157.19 (4) | Ca1xix—O7—Ca2ii | 88.96 (5) |
O3—Ca3—P2xi | 127.42 (4) | Ca3—O7—Ca2ii | 106.08 (5) |
O6xii—Ca3—P2xi | 86.31 (3) | P1—O8—Ca2xxiv | 140.73 (9) |
O1—Ca3—P2xi | 79.60 (4) | P1—O8—Ca1ii | 122.93 (8) |
O3xi—Ca3—P2xi | 30.34 (4) | Ca2xxiv—O8—Ca1ii | 95.07 (4) |
O9ii—Ca3—P2xi | 129.09 (4) | P1—O8—Na1xiv | 78.17 (7) |
O7—Ca3—P2xi | 88.54 (3) | Ca2xxiv—O8—Na1xiv | 92.98 (5) |
O8xi—Ca3—P2xi | 95.99 (3) | Ca1ii—O8—Na1xiv | 118.54 (6) |
O10xi—Ca3—P3ii | 127.25 (4) | P1—O8—Na2xiii | 85.19 (7) |
O4ii—Ca3—P3ii | 29.19 (3) | Ca2xxiv—O8—Na2xiii | 84.68 (5) |
O3—Ca3—P3ii | 70.62 (4) | Ca1ii—O8—Na2xiii | 90.87 (5) |
O6xii—Ca3—P3ii | 84.41 (4) | Na1xiv—O8—Na2xiii | 150.58 (6) |
O1—Ca3—P3ii | 125.51 (4) | P1—O8—Ca3xiii | 85.19 (7) |
O3xi—Ca3—P3ii | 156.82 (4) | Ca2xxiv—O8—Ca3xiii | 84.68 (5) |
O9ii—Ca3—P3ii | 29.35 (3) | Ca1ii—O8—Ca3xiii | 90.87 (5) |
O7—Ca3—P3ii | 88.64 (3) | Na1xiv—O8—Ca3xiii | 150.58 (6) |
O8xi—Ca3—P3ii | 101.07 (3) | P3—O9—Ca2 | 133.09 (9) |
P2xi—Ca3—P3ii | 154.84 (2) | P3—O9—Na1vi | 116.32 (10) |
O10xi—Ca3—P2 | 97.15 (4) | Ca2—O9—Na1vi | 100.66 (9) |
O4ii—Ca3—P2 | 92.78 (3) | P3—O9—Na2i | 92.61 (7) |
O3—Ca3—P2 | 28.75 (4) | Ca2—O9—Na2i | 114.25 (6) |
O6xii—Ca3—P2 | 162.04 (4) | Na1vi—O9—Na2i | 92.91 (5) |
O1—Ca3—P2 | 77.50 (4) | P3—O9—Ca3i | 92.61 (7) |
O3xi—Ca3—P2 | 125.12 (4) | Ca2—O9—Ca3i | 114.25 (6) |
O9ii—Ca3—P2 | 69.69 (3) | Na1vi—O9—Ca3i | 92.91 (5) |
O7—Ca3—P2 | 29.22 (3) | P2—O10—Na2xiii | 97.59 (6) |
O8xi—Ca3—P2 | 118.66 (3) | P2—O10—Ca3xiii | 97.59 (6) |
P2xi—Ca3—P2 | 110.03 (2) | P2—O10—Ca1xxv | 128.42 (7) |
P3ii—Ca3—P2 | 77.633 (16) | Na2xiii—O10—Ca1xxv | 109.51 (5) |
O1—P1—O8xiii | 109.11 (6) | Ca3xiii—O10—Ca1xxv | 109.51 (5) |
O1—P1—O8xi | 109.11 (6) | P2—O10—Ca2i | 94.01 (6) |
O8xiii—P1—O8xi | 109.83 (6) | Na2xiii—O10—Ca2i | 132.53 (6) |
O1—P1—O8 | 109.11 (6) | Ca3xiii—O10—Ca2i | 132.53 (6) |
O8xiii—P1—O8 | 109.83 (6) | Ca1xxv—O10—Ca2i | 98.17 (5) |
Symmetry codes: (i) −y+1, x−y+1, z; (ii) −x+y, −x+1, z; (iii) −x+y+2/3, y+1/3, z−1/6; (iv) −y+2/3, −x+4/3, z−1/6; (v) −y+5/3, −x+4/3, z−1/6; (vi) x, y+1, z; (vii) −x+y+1/3, y+2/3, z+1/6; (viii) −x+y−2/3, y−1/3, z+1/6; (ix) x+1/3, x−y+5/3, z+1/6; (x) −y+4/3, −x+5/3, z+1/6; (xi) −x+y+1, −x+1, z; (xii) x+1, y, z; (xiii) −y+1, x−y, z; (xiv) −y+2/3, −x+1/3, z−1/6; (xv) x, y−1, z; (xvi) −x+y−1, −x, z; (xvii) −y+1/3, −x+2/3, z+1/6; (xviii) x−2/3, x−y−1/3, z+1/6; (xix) −x+y+1/3, y−1/3, z+1/6; (xx) x−1, y−1, z; (xxi) −x+y−1/3, y+1/3, z−1/6; (xxii) x−1/3, x−y+4/3, z−1/6; (xxiii) x−1, y, z; (xxiv) −x+y−1/3, y−2/3, z−1/6; (xxv) −y+4/3, −x+2/3, z+1/6. |
Experimental details
Crystal data | |
Chemical formula | Ca8.42Na1.16V(PO4)7 |
Mr | 1079.88 |
Crystal system, space group | Trigonal, R3c |
Temperature (K) | 173 |
a, c (Å) | 10.3273 (3), 37.098 (2) |
V (Å3) | 3426.5 (2) |
Z | 6 |
Radiation type | Mo Kα |
µ (mm−1) | 2.97 |
Crystal size (mm) | 0.18 × 0.16 × 0.06 |
Data collection | |
Diffractometer | Bruker SMART APEX CCD diffractometer |
Absorption correction | Multi-scan |
Tmin, Tmax | 0.615, 0.841 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 9009, 1818, 1808 |
Rint | 0.014 |
(sin θ/λ)max (Å−1) | 0.664 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.016, 0.048, 1.12 |
No. of reflections | 1818 |
No. of parameters | 143 |
No. of restraints | 2 |
Δρmax, Δρmin (e Å−3) | 0.35, −0.67 |
Absolute structure | Flack (1983), 875 Friedel pairs |
Absolute structure parameter | 0.0 (3) |
Computer programs: SMART (Bruker, 1997), SMART, SAINT (Bruker, 1997), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), JANA2000 (Petricek & Dusek, 2000), JANA2000.
V—O5 | 2.0276 (16) | Ca3—O3 | 2.4772 (13) |
V—O2 | 2.0416 (16) | Ca3—O6ix | 2.4852 (14) |
Ca1—O7i | 2.3131 (14) | Ca3—O1 | 2.5084 (8) |
Ca1—O3ii | 2.3569 (16) | Ca3—O3viii | 2.5608 (13) |
Ca1—O8ii | 2.4071 (15) | Ca3—O9iv | 2.6349 (16) |
Ca1—O10iii | 2.4681 (14) | Ca3—O7 | 2.6411 (15) |
Ca1—O4 | 2.4694 (13) | Ca3—O8viii | 2.9784 (16) |
Ca1—O5iv | 2.5135 (14) | P1—O1 | 1.528 (3) |
Ca1—O5 | 2.5222 (14) | P1—O8 | 1.5399 (12) |
Ca1—O6iv | 2.7679 (15) | P2—O3 | 1.5196 (16) |
Ca2—O8v | 2.3215 (14) | P2—O7 | 1.5224 (15) |
Ca2—O4vi | 2.3735 (13) | P2—O10 | 1.5323 (14) |
Ca2—O9 | 2.4008 (15) | P2—O2iv | 1.5674 (16) |
Ca2—O6vii | 2.4515 (13) | P3—O9 | 1.5220 (15) |
Ca2—O2ii | 2.4582 (13) | P3—O6 | 1.5233 (14) |
Ca2—O2 | 2.4830 (13) | P3—O4 | 1.5399 (14) |
Ca2—O10iv | 2.6080 (14) | P3—O5 | 1.5838 (16) |
Ca2—O7ii | 2.6540 (15) | Na1—O9x | 2.4741 (16) |
Ca3—O10viii | 2.3932 (14) | Na1—O8xi | 2.830 (3) |
Ca3—O4iv | 2.4217 (13) |
Symmetry codes: (i) −x+y+2/3, y+1/3, z−1/6; (ii) −y+1, x−y+1, z; (iii) −y+2/3, −x+4/3, z−1/6; (iv) −x+y, −x+1, z; (v) −x+y+1/3, y+2/3, z+1/6; (vi) −x+y−2/3, y−1/3, z+1/6; (vii) x+1/3, x−y+5/3, z+1/6; (viii) −x+y+1, −x+1, z; (ix) x+1, y, z; (x) x, y−1, z; (xi) −y+1/3, −x+2/3, z+1/6. |
The mineral whitlockite, Ca18.19(Mg1.17Fe0.83)H1.62(PO4)14 (Calvo & Gopal, 1975), is isomorphous with β-Ca3(PO4)2 (Dickens et al., 1974). Some whitlockite-like phases, such as M9A(XO4)7 (M = Ca and Sr, A is a rare-earth or transition metal, and X = P, V and As), show ferroelectric phase transitions or nonlinear optical properties, which make them potentially useful for practical applications. β-Ca3(PO4)2 crystallizes in the rhombohedral space group R3c, with unit-cell parameters a = 10.439 Å and c = 37.375 Å. The structure contains six metal (M1–M6) and three phosphorus (P1–P3) positions; M1–M3, P2 and P3 are in general (18b) positions, while M4–M6 and P1 are in special (6a) positions with a 3 point symmetry. Different combinations of occupied and unoccupied M1–M6 positions provide a basis for the large number of compounds that belong to the whitlockite structure type.
In the rhombohedral M9A(XO4)7 (M = Ca and Sr) whitlockites, M1–M3 are in eightfold coordination, M4 in ninefold coordination and M5 in octahedral coordination. The Ca and Sr atoms occupy the M1–M3 positions, while the M5 position is usually occupied by a trivalent cation (A = Al, Sc, Ga, Cr, Fe, In, Y and rare-earth metals). All P atoms are located at the centers of the PO4 phosphate groups, and small cations, such as V5+ or As5+, may also be accommodated in the P positions (Gopal & Calvo, 1971, 1973). In the case of M = Ca, all known compounds have non-centrosymmetric rhombohedral lattices (space group R3c or R3) with unit cells similar to that of β-Ca3(PO4)2 (Belik et al., 1997; Belik, Morozov, Kotov et al., 2000; Belik, Morozov, Grechkin et al., 2000; Belik, Grechkin et al., 2000; Golubev & Lazoryak, 1990, 1991; Evans et al., 2001; Lazoryak et al., 1996). The Ca9A(PO4)7 compounds (A = Fe or In) exhibit a reversible phase transition to a high-temperature centrosymmetric phase (space group R3c; Lazoryak et al., 2003; Morozov et al., 2002). The Sr9A(PO4)7 compounds [A = Sc, Cr, Fe, Ga and In (Belik, Izumi, Ikeda, Okui et al., 2002), or A = Y and Gd–Lu (Belik, Izumi, Ikeda, Lazoryak et al., 2002)] reveal a monoclinic distortion of the whitlockite-like structure. The corresponding vanadates all have a rhombohedral symmetry (Belik et al., 2005).
All M9A(XO4)7 compounds mentioned above may be easily synthesized by annealing mixtures of the corresponding oxides and phosphates in air, since the A cation is always in its highest or most stable oxidation state. At the same time, the M5 position of the whitlockite structure may be occupied by other trivalent cations. In this work, we demonstrate that V3+ can be accommodated within the whitlockite structure if the synthetic conditions prevent the oxidation of vanadium. Initially, this compound was synthesized accidentally during our study of the vanadyl(IV) phosphates, Na2MVO(PO4)2 (M = Ca and Sr; Chernaya et al., 2004), which melt incongruently with disproportionation of the V4+ cations.
The overall composition for the crystal investigated is Ca8.42Na1.16V(PO4)7. Its crystal structure was found to be similar to those of other Ca9A(PO4)7 compounds (Fig. 1). The VO6 octahedra share all six corners with PO4 tetrahedra, forming isolated anionic groups. Additional isolated P1O4 tetrahedra are also present in the structure. The Ca and Na cations randomly occupy interstices between the vanadium and phosphorus polyhedra.
All V–O distances are in the range 2.00–2.05 Å. The V atom is situated in a nearly regular octahedron that is typical for V3+. The calculated bond valence sum (BVS) of 2.89 is close to the estimated value of 3. The PO4 tetrahedra are almost regular, with the P–O distances ranging from 1.5196 (16) to 1.5838 (16) Å, and the BVS values are 4.99, 5.01, and 4.90 for atoms P1, P2 and P3, respectively. Atoms Ca1 and Ca2 exhibit coordination number eight, while atom Ca3 has a ninth O-atom neighbour located at 2.9784 (16) Å. The BVS values for atoms Ca1–Ca3 are 2.12, 2.14 and 1.93, respectively. It should be rememebered that the valence values estimated from the BVS calculations (Brown & Altermatt, 1985) are slightly conservative since the diffraction experiment was performed at low temperature. The lower BVS value for atom Ca3 may be caused by the presence of sodium in the M3 position. The Na atom occupying the M4 position is surrounded by six O atoms. However, the Na–O separations are significantly different, viz. three short distances equal to 2.4741 (16) Å and three long ones at 2.830 (3) Å.
As mentioned above, there are different possibilities for distribution of the metal atoms among the M1–M6 positions of the whitlockite structure. The filling of these positions in the Ca8.42Na1.16V(PO4)7 structure is somewhat similar to that observed previously in other Ca9M(PO4)7 phosphates (M = Li, Na and K, and A = Mg, Ca, Mn and Co (Morozov et al., 1997, 2000; Belik et al., 1999, 2001) or in the Ca10K(VO4)7 vanadate (Mueller-Buschbaum & Schrandt, 1996). In the latter structures, the alkali cations fully occupy the M4 position and, therefore, the divalent cation may be accommodated in the M5 position to keep electroneutrality of the compound. On the other hand, a monovalent cation can replace calcium in one of the M1–M3 positions, similar to what is found in Ca18Na3Fe(PO4)14 (Strunenkova et al., 1997). Thus, Ca8.42Na1.16V(PO4)7 demonstrates a coexistence of both types of alkali cations incorporated in the whitlockite-type structure. The observed distribution is necessary to maintain the trivalent state of the vanadium atoms.
We attempted to prepare an Na-free calcium vanadium phosphate, Ca9V(PO4)7, by annealing a stoichiometric mixture of Ca3(PO4)2, Ca2P2O7 and V2O3 in an evacuated silica tube at different temperatures (1023–1473 K). These reactions always resulted in multi-phase mixtures containing a whitlockite-like phase along with minor (5% or less) amounts of unknown species. On the other hand, an addition of even small amounts of sodium pyrophosphate to the reaction mixture resulted in the formation of a pure whitlockite phase. The latter result suggests that, in the case of A = VIII, the presence of Na atoms causes the whitlockite-type structure to be more stable than in the case of the Ca9A(PO4)7 phosphate.