Buy article online - an online subscription or single-article purchase is required to access this article.
The title compound, dipotassium tri-μ-arsenato-scandium(III)tin(IV), is the first arsenate-containing langbeinite to be characterized by single-crystal methods and crystallizes in the aristotype P213 cubic symmetry for this structure type in which the K+ ions and the octahedral scandium and tin cations lie on crystallographic threefold axes. The ScIII and SnIV ions show a slight segregation over the two octahedral sites, with Sc/Sn populations of 0.582 (5):0.418 (5) on one site and 0.418 (5):0.582 (5) on the other. Bond-valence-sum calculations indicate that the K+ ions are significantly underbonded in this structure and the O atoms show large anisotropic displacement parameters, as also seen in other langbeinites. The crystal studied was found to be a merohedral twin with a 0.690 (16):0.310 (16) domain ratio.
Supporting information
Data collection: SMART (Bruker, 1999); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).
dipotassium tri-µ-arsenato-scandium(III)tin(IV)
top
Crystal data top
K2ScSn(AsO4)3 | Dx = 3.897 Mg m−3 |
Mr = 658.62 | Mo Kα radiation, λ = 0.71073 Å |
Cubic, P213 | Cell parameters from 6789 reflections |
Hall symbol: P 2ac 2ab 3 | θ = 3.4–33.8° |
a = 10.3927 (4) Å | µ = 12.41 mm−1 |
V = 1122.50 (7) Å3 | T = 298 K |
Z = 4 | Cube, colourless |
F(000) = 1216 | 0.10 × 0.10 × 0.10 mm |
Data collection top
Bruker SMART1000 CCD diffractometer | 1522 independent reflections |
Radiation source: fine-focus sealed tube | 1423 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.046 |
ω scans | θmax = 34.2°, θmin = 3.4° |
Absorption correction: multi-scan (SADABS; Bruker, 1999) | h = −13→16 |
Tmin = 0.370, Tmax = 0.370 | k = −16→13 |
12634 measured reflections | l = −16→16 |
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)] = 0.027 | w = 1/[σ2(Fo2) + (0.025P)2 + 7.5919P] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.063 | (Δ/σ)max = 0.002 |
S = 0.97 | Δρmax = 1.43 e Å−3 |
1522 reflections | Δρmin = −1.40 e Å−3 |
60 parameters | Absolute structure: Flack (1983), 638 Friedel pairs |
0 restraints | Absolute structure parameter: 0.310 (16) |
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 | Occ. (<1) |
K1 | 0.56858 (12) | 0.56858 (12) | 0.56858 (12) | 0.0332 (5) | |
K2 | 0.79379 (17) | 0.79379 (17) | 0.79379 (17) | 0.0496 (7) | |
Sc1 | 0.36206 (4) | 0.36206 (4) | 0.36206 (4) | 0.00854 (18) | 0.582 (5) |
Sn1 | 0.36206 (4) | 0.36206 (4) | 0.36206 (4) | 0.00854 (18) | 0.418 (5) |
Sc2 | 0.08755 (3) | 0.08755 (3) | 0.08755 (3) | 0.01036 (12) | 0.418 (5) |
Sn2 | 0.08755 (3) | 0.08755 (3) | 0.08755 (3) | 0.01036 (12) | 0.582 (5) |
As1 | 0.27347 (4) | 0.37301 (4) | 0.04504 (4) | 0.01062 (10) | |
O1 | 0.2652 (5) | 0.4234 (5) | 0.1973 (4) | 0.0399 (12) | |
O2 | 0.4228 (4) | 0.3475 (6) | −0.0029 (5) | 0.0446 (12) | |
O3 | 0.2014 (6) | 0.2312 (5) | 0.0196 (6) | 0.0551 (16) | |
O4 | 0.1963 (5) | 0.4770 (5) | −0.0483 (5) | 0.0479 (14) | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
K1 | 0.0332 (5) | 0.0332 (5) | 0.0332 (5) | −0.0040 (5) | −0.0040 (5) | −0.0040 (5) |
K2 | 0.0496 (7) | 0.0496 (7) | 0.0496 (7) | −0.0047 (7) | −0.0047 (7) | −0.0047 (7) |
Sc1 | 0.00854 (18) | 0.00854 (18) | 0.00854 (18) | 0.00023 (13) | 0.00023 (13) | 0.00023 (13) |
Sn1 | 0.00854 (18) | 0.00854 (18) | 0.00854 (18) | 0.00023 (13) | 0.00023 (13) | 0.00023 (13) |
Sc2 | 0.01036 (12) | 0.01036 (12) | 0.01036 (12) | −0.00140 (11) | −0.00140 (11) | −0.00140 (11) |
Sn2 | 0.01036 (12) | 0.01036 (12) | 0.01036 (12) | −0.00140 (11) | −0.00140 (11) | −0.00140 (11) |
As1 | 0.01130 (18) | 0.01061 (18) | 0.00995 (18) | −0.00112 (13) | −0.00005 (13) | 0.00235 (13) |
O1 | 0.064 (3) | 0.044 (3) | 0.0122 (17) | 0.026 (2) | −0.0073 (18) | −0.0090 (16) |
O2 | 0.025 (2) | 0.056 (3) | 0.053 (3) | 0.008 (2) | 0.019 (2) | 0.014 (2) |
O3 | 0.073 (4) | 0.039 (3) | 0.054 (3) | −0.040 (3) | 0.000 (3) | 0.001 (2) |
O4 | 0.055 (3) | 0.054 (3) | 0.035 (2) | 0.027 (2) | 0.002 (2) | 0.029 (2) |
Geometric parameters (Å, º) top
K1—O2i | 2.980 (6) | Sc1—O1x | 2.086 (4) |
K1—O2ii | 2.980 (6) | Sc1—O1xi | 2.086 (4) |
K1—O2iii | 2.980 (6) | Sc1—O1 | 2.086 (4) |
K1—O4iv | 3.046 (6) | Sc2—O3xi | 2.032 (5) |
K1—O4v | 3.046 (6) | Sc2—O3 | 2.032 (5) |
K1—O4vi | 3.046 (6) | Sc2—O3x | 2.032 (5) |
K1—O3i | 3.068 (7) | Sc2—O2xii | 2.040 (4) |
K1—O3ii | 3.068 (7) | Sc2—O2xiii | 2.040 (4) |
K1—O3iii | 3.068 (7) | Sc2—O2xiv | 2.040 (4) |
K2—O1vii | 2.956 (5) | As1—O2 | 1.651 (4) |
K2—O1viii | 2.956 (5) | As1—O3 | 1.674 (5) |
K2—O1ix | 2.956 (5) | As1—O4 | 1.659 (4) |
K2—O4i | 3.185 (6) | As1—O1 | 1.669 (4) |
K2—O4ii | 3.185 (6) | O1—K2xv | 2.956 (5) |
K2—O4iii | 3.185 (6) | O2—Sc2xvi | 2.040 (4) |
K2—O3ii | 3.322 (6) | O2—K1xvii | 2.980 (6) |
K2—O3i | 3.322 (6) | O3—K1xvii | 3.068 (7) |
K2—O3iii | 3.322 (6) | O3—K2xvii | 3.322 (6) |
Sc1—O4v | 2.008 (4) | O4—Sc1xviii | 2.008 (4) |
Sc1—O4iv | 2.008 (4) | O4—K1xviii | 3.046 (6) |
Sc1—O4vi | 2.008 (4) | O4—K2xvii | 3.185 (6) |
| | | |
O2i—K1—O2ii | 101.56 (14) | O3ii—K2—O3i | 80.0 (2) |
O2i—K1—O2iii | 101.56 (14) | O1vii—K2—O3iii | 162.73 (15) |
O2ii—K1—O2iii | 101.56 (14) | O1viii—K2—O3iii | 103.12 (12) |
O2i—K1—O4iv | 95.01 (14) | O1ix—K2—O3iii | 83.83 (16) |
O2ii—K1—O4iv | 100.72 (15) | O4i—K2—O3iii | 127.21 (16) |
O2iii—K1—O4iv | 148.84 (14) | O4ii—K2—O3iii | 82.30 (13) |
O2i—K1—O4v | 100.72 (15) | O4iii—K2—O3iii | 48.02 (12) |
O2ii—K1—O4v | 148.84 (14) | O3ii—K2—O3iii | 80.0 (2) |
O2iii—K1—O4v | 95.01 (14) | O3i—K2—O3iii | 80.0 (2) |
O4iv—K1—O4v | 55.73 (14) | O4v—Sc1—O4iv | 90.3 (2) |
O2i—K1—O4vi | 148.84 (14) | O4v—Sc1—O4vi | 90.3 (2) |
O2ii—K1—O4vi | 95.01 (14) | O4iv—Sc1—O4vi | 90.3 (2) |
O2iii—K1—O4vi | 100.72 (15) | O4v—Sc1—O1x | 90.7 (2) |
O4iv—K1—O4vi | 55.73 (14) | O4iv—Sc1—O1x | 88.89 (19) |
O4v—K1—O4vi | 55.73 (14) | O4vi—Sc1—O1x | 178.7 (2) |
O2i—K1—O3i | 51.10 (12) | O4v—Sc1—O1xi | 178.7 (2) |
O2ii—K1—O3i | 116.90 (17) | O4iv—Sc1—O1xi | 90.7 (2) |
O2iii—K1—O3i | 51.46 (13) | O4vi—Sc1—O1xi | 88.89 (19) |
O4iv—K1—O3i | 132.12 (16) | O1x—Sc1—O1xi | 90.1 (2) |
O4v—K1—O3i | 94.07 (14) | O4v—Sc1—O1 | 88.89 (19) |
O4vi—K1—O3i | 139.67 (16) | O4iv—Sc1—O1 | 178.7 (2) |
O2i—K1—O3ii | 51.46 (13) | O4vi—Sc1—O1 | 90.7 (2) |
O2ii—K1—O3ii | 51.10 (12) | O1x—Sc1—O1 | 90.1 (2) |
O2iii—K1—O3ii | 116.90 (17) | O1xi—Sc1—O1 | 90.1 (2) |
O4iv—K1—O3ii | 94.07 (14) | O3xi—Sc2—O3 | 91.7 (2) |
O4v—K1—O3ii | 139.67 (16) | O3xi—Sc2—O3x | 91.7 (2) |
O4vi—K1—O3ii | 132.12 (16) | O3—Sc2—O3x | 91.7 (2) |
O3i—K1—O3ii | 88.17 (17) | O3xi—Sc2—O2xii | 80.4 (2) |
O2i—K1—O3iii | 116.90 (17) | O3—Sc2—O2xii | 169.4 (3) |
O2ii—K1—O3iii | 51.46 (13) | O3x—Sc2—O2xii | 95.5 (2) |
O2iii—K1—O3iii | 51.10 (12) | O3xi—Sc2—O2xiii | 169.4 (3) |
O4iv—K1—O3iii | 139.67 (16) | O3—Sc2—O2xiii | 95.5 (2) |
O4v—K1—O3iii | 132.12 (16) | O3x—Sc2—O2xiii | 80.4 (2) |
O4vi—K1—O3iii | 94.07 (14) | O2xii—Sc2—O2xiii | 93.3 (2) |
O3i—K1—O3iii | 88.17 (17) | O3xi—Sc2—O2xiv | 95.5 (2) |
O3ii—K1—O3iii | 88.17 (17) | O3—Sc2—O2xiv | 80.4 (2) |
O1vii—K2—O1viii | 94.13 (16) | O3x—Sc2—O2xiv | 169.4 (3) |
O1vii—K2—O1ix | 94.13 (16) | O2xii—Sc2—O2xiv | 93.3 (2) |
O1viii—K2—O1ix | 94.13 (16) | O2xiii—Sc2—O2xiv | 93.3 (2) |
O1vii—K2—O4i | 55.52 (11) | O2—As1—O3 | 103.4 (3) |
O1viii—K2—O4i | 82.43 (14) | O2—As1—O4 | 112.5 (3) |
O1ix—K2—O4i | 148.83 (16) | O3—As1—O4 | 105.3 (3) |
O1vii—K2—O4ii | 82.43 (14) | O2—As1—O1 | 112.7 (3) |
O1viii—K2—O4ii | 148.83 (16) | O3—As1—O1 | 113.7 (3) |
O1ix—K2—O4ii | 55.52 (11) | O4—As1—O1 | 109.0 (2) |
O4i—K2—O4ii | 119.04 (3) | As1—O1—Sc1 | 131.1 (3) |
O1vii—K2—O4iii | 148.83 (16) | As1—O1—K2xv | 109.7 (2) |
O1viii—K2—O4iii | 55.52 (11) | Sc1—O1—K2xv | 103.26 (17) |
O1ix—K2—O4iii | 82.43 (14) | As1—O2—Sc2xvi | 150.0 (3) |
O4i—K2—O4iii | 119.04 (3) | As1—O2—K1xvii | 104.7 (2) |
O4ii—K2—O4iii | 119.04 (3) | Sc2xvi—O2—K1xvii | 101.41 (19) |
O1vii—K2—O3ii | 83.83 (16) | As1—O3—Sc2 | 148.5 (4) |
O1viii—K2—O3ii | 162.73 (15) | As1—O3—K1xvii | 100.6 (3) |
O1ix—K2—O3ii | 103.12 (12) | Sc2—O3—K1xvii | 98.8 (2) |
O4i—K2—O3ii | 82.30 (13) | As1—O3—K2xvii | 88.6 (2) |
O4ii—K2—O3ii | 48.02 (12) | Sc2—O3—K2xvii | 119.6 (2) |
O4iii—K2—O3ii | 127.21 (16) | K1xvii—O3—K2xvii | 78.65 (15) |
O1vii—K2—O3i | 103.12 (12) | As1—O4—Sc1xviii | 163.7 (4) |
O1viii—K2—O3i | 83.83 (16) | As1—O4—K1xviii | 95.9 (2) |
O1ix—K2—O3i | 162.73 (15) | Sn1xviii—O4—K1xviii | 92.40 (17) |
O4i—K2—O3i | 48.02 (13) | As1—O4—K2xvii | 93.6 (2) |
O4ii—K2—O3i | 127.21 (16) | Sc1xviii—O4—K2xvii | 97.83 (19) |
O4iii—K2—O3i | 82.30 (13) | K1xviii—O4—K2xvii | 104.82 (18) |
| | | |
O2—As1—O1—Sc1 | −43.1 (5) | O4—As1—O3—K2xvii | 44.5 (3) |
O3—As1—O1—Sc1 | 74.2 (5) | O1—As1—O3—K2xvii | 163.82 (19) |
O4—As1—O1—Sc1 | −168.6 (4) | O3xi—Sc2—O3—As1 | −74.4 (6) |
O2—As1—O1—K2xv | 86.4 (3) | O3x—Sc2—O3—As1 | 17.4 (7) |
O3—As1—O1—K2xv | −156.4 (3) | O2xii—Sc2—O3—As1 | −115.6 (13) |
O4—As1—O1—K2xv | −39.2 (3) | O2xiii—Sc2—O3—As1 | 97.8 (8) |
O4v—Sc1—O1—As1 | 165.5 (5) | O2xiv—Sc2—O3—As1 | −169.7 (8) |
O4vi—Sc1—O1—As1 | 75.2 (4) | O3xi—Sc2—O3—K1xvii | 53.0 (3) |
O1x—Sc1—O1—As1 | −103.8 (3) | O3x—Sc2—O3—K1xvii | 144.74 (17) |
O1xi—Sc1—O1—As1 | −13.7 (5) | O2xii—Sc2—O3—K1xvii | 11.8 (14) |
O4v—Sc1—O1—K2xv | 33.9 (2) | O2xiii—Sc2—O3—K1xvii | −134.8 (2) |
O4vi—Sc1—O1—K2xv | −56.4 (2) | O2xiv—Sc2—O3—K1xvii | −42.3 (2) |
O1x—Sc1—O1—K2xv | 124.6 (3) | O3xi—Sc2—O3—K2xvii | 134.8 (4) |
O1xi—Sc1—O1—K2xv | −145.3 (2) | O3x—Sc2—O3—K2xvii | −133.4 (4) |
O3—As1—O2—Sn2xvi | 144.9 (7) | O2xii—Sc2—O3—K2xvii | 93.6 (13) |
O4—As1—O2—Sn2xvi | 31.8 (8) | O2xiii—Sc2—O3—K2xvii | −52.9 (3) |
O1—As1—O2—Sn2xvi | −91.8 (7) | O2xiv—Sc2—O3—K2xvii | 39.6 (3) |
O3—As1—O2—Sc2xvi | 144.9 (7) | O2—As1—O4—Sn1xviii | −69.8 (12) |
O4—As1—O2—Sc2xvi | 31.8 (8) | O3—As1—O4—Sn1xviii | 178.3 (11) |
O1—As1—O2—Sc2xvi | −91.8 (7) | O1—As1—O4—Sn1xviii | 55.9 (12) |
O3—As1—O2—K1xvii | −4.7 (3) | O2—As1—O4—Sc1xviii | −69.8 (12) |
O4—As1—O2—K1xvii | −117.9 (3) | O3—As1—O4—Sc1xviii | 178.3 (11) |
O1—As1—O2—K1xvii | 118.5 (2) | O1—As1—O4—Sc1xviii | 55.9 (12) |
O2—As1—O3—Sc2 | 131.5 (8) | O2—As1—O4—K1xviii | 170.1 (2) |
O4—As1—O3—Sc2 | −110.3 (8) | O3—As1—O4—K1xviii | 58.2 (3) |
O1—As1—O3—Sc2 | 9.0 (9) | O1—As1—O4—K1xviii | −64.2 (3) |
O2—As1—O3—K1xvii | 4.5 (3) | O2—As1—O4—K2xvii | 64.8 (3) |
O4—As1—O3—K1xvii | 122.7 (2) | O3—As1—O4—K2xvii | −47.1 (3) |
O1—As1—O3—K1xvii | −118.0 (2) | O1—As1—O4—K2xvii | −169.5 (2) |
O2—As1—O3—K2xvii | −73.7 (2) | | |
Symmetry codes: (i) −z+1/2, −x+1, y+1/2; (ii) y+1/2, −z+1/2, −x+1; (iii) −x+1, y+1/2, −z+1/2; (iv) z+1/2, −x+1/2, −y+1; (v) −x+1/2, −y+1, z+1/2; (vi) −y+1, z+1/2, −x+1/2; (vii) −z+1, x+1/2, −y+3/2; (viii) x+1/2, −y+3/2, −z+1; (ix) −y+3/2, −z+1, x+1/2; (x) z, x, y; (xi) y, z, x; (xii) −z, x−1/2, −y+1/2; (xiii) x−1/2, −y+1/2, −z; (xiv) −y+1/2, −z, x−1/2; (xv) x−1/2, −y+3/2, −z+1; (xvi) x+1/2, −y+1/2, −z; (xvii) −x+1, y−1/2, −z+1/2; (xviii) −x+1/2, −y+1, z−1/2. |
Subscribe to Acta Crystallographica Section C: Structural Chemistry
The full text of this article is available to subscribers to the journal.
If you have already registered and are using a computer listed in your registration details, please email
support@iucr.org for assistance.