Antimony trisulfide

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Antimony trisulfide
Identifiers
CAS number 1345-04-6
Properties
Molecular formula Sb2S3
Molar mass 339.715
Appearance grey / black orthorhombic crystal (stibnite)
Density 6.5g cm-3 (stibnite)[1]
Melting point 620 °C (1,148 °F; 893 K) (stibnite)[1]
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Infobox references

Antimony trisulfide Sb2S3 is found in nature as the crystalline mineral stibnite and the amorphous red mineral metastibnite.[2] It is manufactured for use in safety matches, military ammunition, explosives and fireworks. It also is used in the production of ruby-colored glass and in plastics as a flame retardant.[3] Historically the stibnite form was used as a grey pigment in paintings produced in the 16th century.[4] It is a semiconductor with a direct band gap of 1.8-2.5 eV. With suitable doping p and n type materials can be produced.[5]

Preparation and reactions[edit]

Sb2S3 can be prepared from the elements at temperature 500-900 °C:[3]

2Sb + 3S → Sb2S3

Sb2S3 is precipitated when H2S is passed through an acidified solution of Sb(III).[6] This reaction has been used as a gravimetric method for determining antimony, bubbling H2S through a solution of Sb(III) compound in hot HCl deposits an orange form of Sb2S3 which turns black under the reaction conditions.[7]

Sb2S3 is readily oxidised, reacting vigourously with oxidising agents.[3] It burns in air with a blue flame. It reacts with icandescence with cadmium, magnesium and zinc chlorates. Mixtures of Sb2S3 and chlorates may explode.[8]

In the extraction of antimony from antimony ores the alkaline sulfide process is employed where Sb2S3 reacts to form thioantimonate(III) salts (also called thioantimonite):[9]

3Na2S + Sb2S3 → 2Na3SbS3

A number of salts containing different thioantimonate(III) ions can be prepared from Sb2S3 these include:[10]

[SbS3]3–, [SbS2], [Sb2S5]4–, [Sb4S9]6–, [Sb4S7]2– and [Sb8S17]10–

"Schlippe's salt", Na3SbS4·9H2O, a thioantimonate(V) salt is formed when Sb2S3 is boiled with sulfur and sodium hydroxide. The reaction can be represented as:[6]

Sb2S3 + 3S2– + 2S → 2[SbS4]3–

Structure[edit]

The structure of the black needle like form of Sb2S3, stibnite, consists of linked ribbons in which antimony atoms are in two different coordination environments, trigonal pyramidal and square pyramidal.[6] Similar ribbons occur in Bi2S3 and Sb2Se3.[11] The red form, metastibnite, is amorphous. Recent work suggests that there are a number of closely related temperature dependant structures of stibnite which have been termed stibnite(I) the high temperature form, identified previously, stibnite (II) and stibnite(III).[12]

References[edit]

  1. ^ a b Lide, David R., ed. (2006). CRC Handbook of Chemistry and Physics (87th ed.). Boca Raton, FL: CRC Press. ISBN 0-8493-0487-3. 
  2. ^ SUPERGENE METASTIBNITE FROM MINA ALACRAN, PAMPA LARGA, COPIAPO,CHILE, Alan H Clark, THE AMERICAN MINERALOGIST. VOL.55.,I97O
  3. ^ a b c Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. pp. 581–582. ISBN 0080379419. 
  4. ^ Eastaugh, Nicholas (2004). Pigment Compendium: A Dictionary of Historical Pigments. Butterworth-Heinemann. p. 359. ISBN 0-7506-5749-9. 
  5. ^ Electrochemistry of Metal Chalcogenides, Mirtat Bouroushian, Springer, 2010
  6. ^ a b c Holleman, A. F.; Wiberg, E. (2001), Inorganic Chemistry, San Diego: Academic Press, p. 765-766, ISBN 0-12-352651-5 
  7. ^ A.I. Vogel,(1951), Quantitative Inorganic analysis, (2d edition), Longmans Green and Co
  8. ^ Hazardous Laboratory Chemicals Disposal Guide, Third Edition,CRC Press, 2003, Margaret-Ann Armour, ISBN 9781566705677
  9. ^ Anderson, Corby G. (2012). "The metallurgy of antimony". Chemie der Erde - Geochemistry 72: 3–8. doi:10.1016/j.chemer.2012.04.001. ISSN 0009-2819. 
  10. ^ Inorganic Reactions and Methods, The Formation of Bonds to Group VIB (O, S, Se, Te, Po) Elements (Part 1) (Volume 5) Ed. A.P, Hagen,1991, Wiley-VCH, isbn 0-471-18658-9
  11. ^ Wells A.F. (1984) Structural Inorganic Chemistry 5th edition Oxford Science Publications ISBN 0-19-855370-6
  12. ^ Kuze S., Du Boulay D., Ishizawa N., Saiki A, Pring A.; (2004), X ray diffraction evidence for a monoclinic form of stibnite, Sb2S3, below 290K; American Mineralogist, 9(89), 1022-1025.