Sodium thioantimoniate
 | |
| Names | |
|---|---|
| IUPAC name
Sodium tetrathioantimonate(V) | |
| Properties | |
| Na3SbS4·9H2O | |
| Appearance | Yellow crystals |
| Density | 1.806 g/cm3, solid |
| Melting point | 87 °C (189 °F; 360 K) |
| Related compounds | |
| Other anions |
Potassium thioantimoniate |
| Related compounds |
Antimony(III) sulfide |
| Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
 verify (what is  ?) | |
| Infobox references | |
Sodium thioantimoniate is an inorganic compound with the formula Na3SbS4. The nonahydrate of this material is known as Schlippe's salt, named after K. F. Schlippe (1799–1867), These compounds are examples of sulfosalts. They are mainly of historic interest.
Structure
This hydrated salt consists of the tetrahedral SbS43− anion (rSb-S = 2.33 Å) and sodium cations, which are hydrated.[1][2] Related salts are known for different cations including ammonium and potassium.
The anhydrous salt is polymer with tetrahedral Na and Sb sites.[3]
Preparation
Sodium thioantimoniate is prepared by the reaction of antimony trisulfide, elemental sulfur, and aqueous sulfide source.
- 3 Na2S + 2 S + Sb2S3 + 9 H2O → 2 Na3SbS4·9 H2O
The sulfide can be generated indirectly by the thermal reaction of elemental sulfur with sodium hydroxide or even charcoal:
- Sb2S3 + 8 NaOH + 6 S → 2 Na3SbS4 + Na2SO4 + 4 H2O
In the latter route, a mixture of sodium sulfate (16 parts) is reduced by fusion with charcoal (4-5 parts) in the presence of antimony sulfide (13 parts). The melt is extracted into water which is treated with sulfur (4 parts). Upon evaporation of the solution, the salt crystallizes as large tetrahedra, which are easily soluble in water. The anhydrous salt melts easily on heating, and in the hydrated condition, on exposure to moist air becomes coated with a red film.
The required antimony(III) sulfide is prepared in the usual way by treatment of virtually any Sb(III) compound with sulfide sources:
- 2 SbCl3 + 3 H2S → Sb2S3 + 6 HCl
Reactions
The hydrate dissolves in water to give the tetrahydral SbS43- ion. The salt gives "quinsulfide antimony," upon acidification:
- 2 Na3SbS4 + 6 HCl → Sb2S5 + 6 NaCl + 3 H2S
Related compounds
- Antimony (III) sulfide, Sb2S3
Notes
- ↑ Krebs, B., "Thio- and Seleno Compounds of Main Group Elements - New Inorganic Oligomers and Polymers", Angewandte Chemie, 1983, volume 95, pages 113-34.
- ↑ K. Mereiter, A. Preisinger and H. Guth "Hydrogen bonds in Schlippe's salt: refinement of the crystal structures of Na3SbS4.9H2O by X-ray diffraction and Na3SbS4.9D2O by neutron diffraction at room temperature" Acta Crystallographica 1979, vol. B35, 19-25. doi:10.1107/S0567740879002442.
- ↑ H. A. Graf, H. Schäfer "Zur Strukturchemie der Alkalisalze der Tetrathiosäuren der Elemente der 5. Hauptgruppe (pages 67–80) Zeitschrift fuer Anorganische und Allgemeine Chemie 1976, vol. 425, p67-p80. doi:10.1002/zaac.19764250109
References
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This article incorporates text from a publication now in the public domain: Chisholm, Hugh, ed. (1911). "Schlippe's Salt". Encyclopædia Britannica (11th ed.). Cambridge University Press.