inorganic compounds
Calcium disodium hexathiodiphosphate(IV) octahydrate
aInstitute of Inorganic and Analytical Chemistry, Clausthal University of Technology, Paul-Ernst-Strasse 4, 38678 Clausthal-Zellerfeld, Germany
*Correspondence e-mail: mimoza.gjikaj@tu-clausthal.de
Single crystals of the title compound, CaNa2(P2S6)·8H2O, were obtained by adding calcium hydroxide to an aqueous solution of Na4(P2S6)·6H2O. The structure is isotypic with that of its strontium analogue and consists of one Ca2+ cation, two Na+ cations, one-half of a centrosymmetric (P2S6)4− anion with staggered confirmation and four water molecules in the The can be described as being built up from layers of cations and anions extending parallel to (101). Within a layer, each CaO8 polyhedron is connected via edge-sharing to two NaO4S2 octahedra and to one NaO2S4 octaedron. The NaO4S2 octahedra are, in turn, linked with two (P2S6)4− anions through common corners. Various O—H⋯S hydrogen-bonding interactions lead to cohesion of adjacent layers. The Ca2+ and one Na+ cation are situated on a twofold rotation axis and the second Na+ cation is situated on an inversion centre.
Related literature
For background to thiodiphosphates(IV), including their crystal structures, see: Jörgens et al. (2003); Klingen et al. (1973). For the synthesis of Na4(P2S6)·6H2O, see: Fincher et al. (1998). For the isotypic structure of SrNa2(P2S6)·8H2O, see: Gjikaj & Ehrhardt (2010).
Experimental
Crystal data
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Data collection
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Refinement
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Data collection: X-AREA (Stoe & Cie, 2008); cell X-AREA; data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2004); software used to prepare material for publication: SHELXL97.
Supporting information
https://doi.org/10.1107/S1600536810025304/wm2364sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810025304/wm2364Isup2.hkl
Na4(P2S6).6H2O has been prepared according to Fincher et al. (1998). The new ternary calcium disodium hexathiodiphosphate octahydrate was obtained by adding calcium hydroxide (2 mmol, 0.148 g) to a solution of Na4(P2S6).6H2O (2 mmol, 0.910 g) in 40 ml distilled water at 333 K. Slow cooling to room temperature yielded colorless crystals of the title compound within some days.
Hydrogen atoms were found from the difference Fourier map and were refined independently from their respective oxygen atoms with individual isotropic displacement parameters.
Alkaline earth hypothiodiphosphates were first reported by Klingen et al. (1973). The structure of the title compound is isotypic with that of the strontium analogue, SrNa2(P2S6).8H2O (Ehrhardt & Gjikaj, 2010). The
of CaNa2(P2S6).8H2O contains one Ca2+ cation, two Na+ cations, one half of a (P2S6)4- anion in and four water molecules (Fig. 1).Na(1) is octahedrally coordinated by four H2O molecules and two sulfur atoms of two (P2S6)4- anions (Fig 2). Na(2) is also octahedrally coordinated by two H2O molecules and four sulfur atoms of two (P2S6)4- anions (Fig. 3). The calcium cation is eightfold coordinated by water O atoms. The [CaO8]
can be described as a bicapped trigonal prism. The is built up from layers extending parallel to (101). These layers consists of edge-sharing CaO8 and Na(1)O4S2 polyedra, CaO8 and Na(2)O2S4 polyhadra, as well as corner-sharing Na(1)O4S2 and (P2S6)4- polyhedra.The staggered (P2S6)4- anion is located on a centre of inversion, with a P—P distance of 2.2381 (8) Å. The P—P central bond links two PS3 groups with P—S distances ranging from 2.0156 (6) to 2.0282 (6) Å. These values agree well with those reported previously for another hypothiodiphosphate structure (Jörgens et al., 2003).
Neighbouring layers are held together by various O—H···S hydrogen bonding interactions. The donor—acceptor distances between O atoms of water molecules and S atoms of (P2S6)4- units range from 3.188 to 3.327 Å (Table 2).
For background to thiodiphosphates(IV), including their crystal structures, see: Jörgens et al. (2003); Klingen et al. (1973). For the synthesis of Na4P2S6.6H2O, see: Fincher et al. (1998). For the isotypic structure of SrNa2(P2S6).8H2O, see: Ehrhardt & Gjikaj (2010).
Data collection: X-AREA (Stoe & Cie, 2008); cell
X-AREA (Stoe & Cie, 2008); data reduction: X-AREA (Stoe & Cie, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2004); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).Fig. 1. The crystal structure of CaNa2(P2S6).8H2O in a projection along [010]. | |
Fig. 2. Coordination of Na1 with the atom labelling scheme. The displacement ellipsoids are drawn at the 50% probability level. Symmetry codes as in Table 1. H atoms are represented as spheres of arbirtary radius. | |
Fig. 3. View of the edge-shared CaO8 and Na(2)O2S4 polyhedra with the atom labelling scheme. The displacement ellipsoids are drawn at the 50% probability level. Symmetry codes as in Table 1. H atoms are represented as spheres of arbirtary radius. |
CaNa2(P2S6)·8H2O | F(000) = 992 |
Mr = 484.49 | Dx = 1.852 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -C 2yc | Cell parameters from 15599 reflections |
a = 14.702 (2) Å | θ = 1.0–30.5° |
b = 9.3081 (14) Å | µ = 1.34 mm−1 |
c = 14.052 (2) Å | T = 223 K |
β = 115.383 (11)° | Block, colorless |
V = 1737.3 (4) Å3 | 0.29 × 0.24 × 0.23 mm |
Z = 4 |
Stoe IPDS 2 diffractometer | 2369 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.050 |
Graphite monochromator | θmax = 30.5°, θmin = 2.7° |
ω–scans | h = −20→20 |
15223 measured reflections | k = −13→13 |
2650 independent reflections | l = −20→17 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.029 | All H-atom parameters refined |
wR(F2) = 0.065 | w = 1/[σ2(Fo2) + (0.0256P)2 + 2.2311P] where P = (Fo2 + 2Fc2)/3 |
S = 1.13 | (Δ/σ)max < 0.001 |
2650 reflections | Δρmax = 0.68 e Å−3 |
122 parameters | Δρmin = −0.53 e Å−3 |
0 restraints | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0046 (3) |
CaNa2(P2S6)·8H2O | V = 1737.3 (4) Å3 |
Mr = 484.49 | Z = 4 |
Monoclinic, C2/c | Mo Kα radiation |
a = 14.702 (2) Å | µ = 1.34 mm−1 |
b = 9.3081 (14) Å | T = 223 K |
c = 14.052 (2) Å | 0.29 × 0.24 × 0.23 mm |
β = 115.383 (11)° |
Stoe IPDS 2 diffractometer | 2369 reflections with I > 2σ(I) |
15223 measured reflections | Rint = 0.050 |
2650 independent reflections |
R[F2 > 2σ(F2)] = 0.029 | 0 restraints |
wR(F2) = 0.065 | All H-atom parameters refined |
S = 1.13 | Δρmax = 0.68 e Å−3 |
2650 reflections | Δρmin = −0.53 e Å−3 |
122 parameters |
x | y | z | Uiso*/Ueq | ||
Ca | 0.5000 | 0.24842 (5) | 0.2500 | 0.01531 (10) | |
Na1 | 0.2500 | 0.2500 | 0.0000 | 0.0240 (2) | |
Na2 | 0.5000 | 0.67523 (13) | 0.2500 | 0.0318 (2) | |
P | 0.20227 (3) | 0.76310 (4) | 0.04363 (3) | 0.01394 (9) | |
S1 | 0.06893 (3) | 0.67248 (4) | −0.04913 (3) | 0.02064 (10) | |
S2 | 0.18887 (3) | 0.97575 (4) | 0.06497 (3) | 0.01807 (9) | |
S3 | 0.27954 (3) | 0.66563 (4) | 0.18473 (3) | 0.02051 (10) | |
O1 | 0.59411 (11) | 0.04315 (16) | 0.23418 (13) | 0.0268 (3) | |
O2 | 0.50720 (10) | 0.45732 (14) | 0.14604 (10) | 0.0217 (2) | |
O3 | 0.41702 (10) | 0.16862 (14) | 0.06107 (10) | 0.0216 (2) | |
O4 | 0.31872 (9) | 0.32895 (14) | 0.17753 (10) | 0.0199 (2) | |
H1A | 0.629 (4) | 0.053 (5) | 0.205 (4) | 0.096 (15)* | |
H1B | 0.627 (3) | 0.002 (4) | 0.287 (3) | 0.068 (12)* | |
H2A | 0.554 (3) | 0.462 (3) | 0.133 (3) | 0.048 (9)* | |
H2B | 0.453 (2) | 0.477 (3) | 0.088 (3) | 0.045 (8)* | |
H3A | 0.4123 (19) | 0.085 (3) | 0.059 (2) | 0.029 (6)* | |
H3B | 0.454 (2) | 0.192 (3) | 0.030 (2) | 0.042 (8)* | |
H4A | 0.288 (2) | 0.294 (3) | 0.212 (3) | 0.049 (8)* | |
H4B | 0.306 (2) | 0.416 (3) | 0.172 (2) | 0.040 (7)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Ca | 0.0144 (2) | 0.01655 (19) | 0.01458 (19) | 0.000 | 0.00584 (15) | 0.000 |
Na1 | 0.0192 (5) | 0.0302 (5) | 0.0196 (5) | −0.0001 (4) | 0.0053 (4) | −0.0011 (4) |
Na2 | 0.0283 (6) | 0.0396 (6) | 0.0249 (5) | 0.000 | 0.0089 (4) | 0.000 |
P | 0.01509 (18) | 0.01411 (17) | 0.01436 (17) | 0.00019 (13) | 0.00797 (14) | 0.00016 (12) |
S1 | 0.01688 (19) | 0.02004 (18) | 0.0257 (2) | −0.00401 (14) | 0.00981 (15) | −0.00281 (14) |
S2 | 0.01954 (19) | 0.01504 (17) | 0.01967 (18) | 0.00092 (13) | 0.00844 (14) | −0.00104 (13) |
S3 | 0.0250 (2) | 0.02236 (19) | 0.01657 (17) | 0.00676 (15) | 0.01122 (15) | 0.00515 (14) |
O1 | 0.0201 (6) | 0.0272 (6) | 0.0298 (7) | 0.0039 (5) | 0.0075 (5) | −0.0023 (5) |
O2 | 0.0197 (6) | 0.0261 (6) | 0.0187 (5) | −0.0009 (5) | 0.0076 (5) | 0.0038 (5) |
O3 | 0.0241 (6) | 0.0203 (6) | 0.0227 (6) | 0.0002 (5) | 0.0124 (5) | −0.0026 (5) |
O4 | 0.0210 (6) | 0.0195 (5) | 0.0214 (6) | 0.0014 (4) | 0.0112 (5) | −0.0002 (4) |
Ca—O1 | 2.4244 (14) | Na2—S1iv | 2.9242 (8) |
Ca—O1i | 2.4244 (15) | Na2—S3 | 2.9673 (7) |
Ca—O2 | 2.4614 (13) | Na2—S3i | 2.9674 (7) |
Ca—O2i | 2.4615 (13) | P—S1 | 2.0156 (6) |
Ca—O3i | 2.5122 (13) | P—S2 | 2.0241 (6) |
Ca—O3 | 2.5123 (13) | P—S3 | 2.0282 (6) |
Ca—O4 | 2.5249 (13) | P—Piv | 2.2381 (8) |
Ca—O4i | 2.5249 (13) | S1—Na2iv | 2.9242 (8) |
Na1—O3 | 2.3523 (14) | S2—Na1vi | 2.9768 (5) |
Na1—O3ii | 2.3523 (14) | O1—H1A | 0.78 (5) |
Na1—O4 | 2.3713 (13) | O1—H1B | 0.79 (4) |
Na1—O4ii | 2.3713 (13) | O2—H2A | 0.79 (3) |
Na1—S2iii | 2.9767 (5) | O2—H2B | 0.88 (3) |
Na1—S2iv | 2.9768 (5) | O3—H3A | 0.78 (3) |
Na2—O2 | 2.5282 (17) | O3—H3B | 0.86 (3) |
Na2—O2i | 2.5283 (17) | O4—H4A | 0.85 (3) |
Na2—S1v | 2.9242 (8) | O4—H4B | 0.83 (3) |
O1—Ca—O1i | 75.99 (8) | O4ii—Na1—S2iii | 90.48 (3) |
O1—Ca—O2 | 113.37 (5) | O3—Na1—S2iv | 89.02 (4) |
O1i—Ca—O2 | 148.04 (5) | O3ii—Na1—S2iv | 90.98 (4) |
O1—Ca—O2i | 148.04 (5) | O4—Na1—S2iv | 90.48 (3) |
O1i—Ca—O2i | 113.37 (5) | O4ii—Na1—S2iv | 89.52 (3) |
O2—Ca—O2i | 75.64 (6) | S2iii—Na1—S2iv | 180.0 |
O1—Ca—O3i | 79.99 (5) | O2—Na2—O2i | 73.30 (7) |
O1i—Ca—O3i | 73.01 (5) | O2—Na2—S1v | 149.72 (4) |
O2—Ca—O3i | 137.37 (4) | O2i—Na2—S1v | 85.08 (3) |
O2i—Ca—O3i | 74.41 (4) | O2—Na2—S1iv | 85.08 (3) |
O1—Ca—O3 | 73.01 (5) | O2i—Na2—S1iv | 149.72 (4) |
O1i—Ca—O3 | 79.99 (5) | S1v—Na2—S1iv | 122.01 (5) |
O2—Ca—O3 | 74.42 (4) | O2—Na2—S3 | 96.20 (4) |
O2i—Ca—O3 | 137.37 (4) | O2i—Na2—S3 | 81.01 (4) |
O3i—Ca—O3 | 145.61 (6) | S1v—Na2—S3 | 101.16 (2) |
O1—Ca—O4 | 137.92 (5) | S1iv—Na2—S3 | 80.537 (18) |
O1i—Ca—O4 | 74.08 (5) | O2—Na2—S3i | 81.01 (4) |
O2—Ca—O4 | 80.36 (5) | O2i—Na2—S3i | 96.20 (4) |
O2i—Ca—O4 | 72.44 (4) | S1v—Na2—S3i | 80.537 (17) |
O3i—Ca—O4 | 117.68 (4) | S1iv—Na2—S3i | 101.16 (2) |
O3—Ca—O4 | 73.21 (4) | S3—Na2—S3i | 176.55 (5) |
O1—Ca—O4i | 74.08 (5) | S1—P—S2 | 112.06 (3) |
O1i—Ca—O4i | 137.92 (5) | S1—P—S3 | 115.28 (3) |
O2—Ca—O4i | 72.44 (4) | S2—P—S3 | 109.99 (3) |
O2i—Ca—O4i | 80.36 (5) | S1—P—Piv | 105.34 (3) |
O3i—Ca—O4i | 73.21 (4) | S2—P—Piv | 108.14 (3) |
O3—Ca—O4i | 117.68 (4) | S3—P—Piv | 105.48 (3) |
O4—Ca—O4i | 145.46 (6) | P—S1—Na2iv | 105.07 (3) |
O3—Na1—O3ii | 180.0 | P—S2—Na1vi | 137.04 (2) |
O3—Na1—O4 | 78.97 (4) | P—S3—Na2 | 111.63 (3) |
O3ii—Na1—O4 | 101.03 (4) | H1A—O1—H1B | 105 (4) |
O3—Na1—O4ii | 101.03 (4) | Ca—O2—Na2 | 105.53 (5) |
O3ii—Na1—O4ii | 78.97 (4) | H2A—O2—H2B | 108 (3) |
O4—Na1—O4ii | 179.999 (2) | Na1—O3—Ca | 104.38 (5) |
O3—Na1—S2iii | 90.98 (4) | Na1—O4—Ca | 103.44 (5) |
O3ii—Na1—S2iii | 89.02 (4) | H4A—O4—H4B | 106 (3) |
O4—Na1—S2iii | 89.52 (3) |
Symmetry codes: (i) −x+1, y, −z+1/2; (ii) −x+1/2, −y+1/2, −z; (iii) x, y−1, z; (iv) −x+1/2, −y+3/2, −z; (v) x+1/2, −y+3/2, z+1/2; (vi) x, y+1, z. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1A···S3vii | 0.78 (5) | 2.58 (5) | 3.2922 (17) | 153 (4) |
O1—H1B···S2viii | 0.79 (4) | 2.62 (4) | 3.2892 (16) | 144 (4) |
O2—H2A···S2vii | 0.79 (3) | 2.54 (3) | 3.3270 (15) | 172 (3) |
O2—H2B···S2iv | 0.88 (3) | 2.30 (3) | 3.1877 (15) | 179 (3) |
O3—H3A···S1ii | 0.78 (3) | 2.43 (3) | 3.1908 (15) | 168 (2) |
O3—H3B···S1vii | 0.86 (3) | 2.39 (3) | 3.2174 (14) | 161 (3) |
O4—H4A···S3ix | 0.85 (3) | 2.41 (3) | 3.2468 (14) | 171 (3) |
O4—H4B···S3 | 0.83 (3) | 2.37 (3) | 3.1957 (14) | 171 (3) |
Symmetry codes: (ii) −x+1/2, −y+1/2, −z; (iv) −x+1/2, −y+3/2, −z; (vii) x+1/2, y−1/2, z; (viii) −x+1, y−1, −z+1/2; (ix) −x+1/2, y−1/2, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | CaNa2(P2S6)·8H2O |
Mr | 484.49 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 223 |
a, b, c (Å) | 14.702 (2), 9.3081 (14), 14.052 (2) |
β (°) | 115.383 (11) |
V (Å3) | 1737.3 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 1.34 |
Crystal size (mm) | 0.29 × 0.24 × 0.23 |
Data collection | |
Diffractometer | Stoe IPDS 2 |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 15223, 2650, 2369 |
Rint | 0.050 |
(sin θ/λ)max (Å−1) | 0.715 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.029, 0.065, 1.13 |
No. of reflections | 2650 |
No. of parameters | 122 |
H-atom treatment | All H-atom parameters refined |
Δρmax, Δρmin (e Å−3) | 0.68, −0.53 |
Computer programs: X-AREA (Stoe & Cie, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 2004).
Ca—O1 | 2.4244 (14) | Na2—O2 | 2.5282 (17) |
Ca—O2 | 2.4614 (13) | Na2—S1i | 2.9242 (8) |
Ca—O3 | 2.5123 (13) | Na2—S3 | 2.9673 (7) |
Ca—O4 | 2.5249 (13) | P—S1 | 2.0156 (6) |
Na1—O3 | 2.3523 (14) | P—S2 | 2.0241 (6) |
Na1—O4 | 2.3713 (13) | P—S3 | 2.0282 (6) |
Na1—S2i | 2.9768 (5) | P—Pi | 2.2381 (8) |
Symmetry code: (i) −x+1/2, −y+3/2, −z. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1A···S3ii | 0.78 (5) | 2.58 (5) | 3.2922 (17) | 153 (4) |
O1—H1B···S2iii | 0.79 (4) | 2.62 (4) | 3.2892 (16) | 144 (4) |
O2—H2A···S2ii | 0.79 (3) | 2.54 (3) | 3.3270 (15) | 172 (3) |
O2—H2B···S2i | 0.88 (3) | 2.30 (3) | 3.1877 (15) | 179 (3) |
O3—H3A···S1iv | 0.78 (3) | 2.43 (3) | 3.1908 (15) | 168 (2) |
O3—H3B···S1ii | 0.86 (3) | 2.39 (3) | 3.2174 (14) | 161 (3) |
O4—H4A···S3v | 0.85 (3) | 2.41 (3) | 3.2468 (14) | 171 (3) |
O4—H4B···S3 | 0.83 (3) | 2.37 (3) | 3.1957 (14) | 171 (3) |
Symmetry codes: (i) −x+1/2, −y+3/2, −z; (ii) x+1/2, y−1/2, z; (iii) −x+1, y−1, −z+1/2; (iv) −x+1/2, −y+1/2, −z; (v) −x+1/2, y−1/2, −z+1/2. |
References
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Alkaline earth hypothiodiphosphates were first reported by Klingen et al. (1973). The structure of the title compound is isotypic with that of the strontium analogue, SrNa2(P2S6).8H2O (Ehrhardt & Gjikaj, 2010). The asymmetric unit of CaNa2(P2S6).8H2O contains one Ca2+ cation, two Na+ cations, one half of a (P2S6)4- anion in staggered conformation and four water molecules (Fig. 1).
Na(1) is octahedrally coordinated by four H2O molecules and two sulfur atoms of two (P2S6)4- anions (Fig 2). Na(2) is also octahedrally coordinated by two H2O molecules and four sulfur atoms of two (P2S6)4- anions (Fig. 3). The calcium cation is eightfold coordinated by water O atoms. The [CaO8] coordination polyhedron can be described as a bicapped trigonal prism. The crystal structure is built up from layers extending parallel to (101). These layers consists of edge-sharing CaO8 and Na(1)O4S2 polyedra, CaO8 and Na(2)O2S4 polyhadra, as well as corner-sharing Na(1)O4S2 and (P2S6)4- polyhedra.
The staggered (P2S6)4- anion is located on a centre of inversion, with a P—P distance of 2.2381 (8) Å. The P—P central bond links two PS3 groups with P—S distances ranging from 2.0156 (6) to 2.0282 (6) Å. These values agree well with those reported previously for another hypothiodiphosphate structure (Jörgens et al., 2003).
Neighbouring layers are held together by various O—H···S hydrogen bonding interactions. The donor—acceptor distances between O atoms of water molecules and S atoms of (P2S6)4- units range from 3.188 to 3.327 Å (Table 2).