Iron(II,III) sulfide

Iron(II,III) sulfide

Names
Other names Ferrous-ferric sulfide, greigite
Identifiers
CAS Number	12063-39-7
3D model (JSmol)	Interactive image
ChEBI	CHEBI:86238
ChemSpider	34999896
PubChem CID	72720442
CompTox Dashboard (EPA)	DTXSID20923500
InChI InChI=1S/3Fe.4S/q+2;2*+3;4*-2 Key: UHUWQCGPGPPDDT-UHFFFAOYSA-N
SMILES [S-2].[S-2].[S-2].[S-2].[Fe+2].[Fe+3].[Fe+3]
Properties
Chemical formula	FeS·Fe2S3
Molar mass	295.805
Appearance	Bluish-black, pinkish
Density	4.049 g/cm^3
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is ^YN ?) Infobox references

Iron(II,III) sulfide is a blue-black (sometimes pinkish^[citation needed]) chemical compound of iron and sulfur with formula Fe₃S₄ or FeS·Fe₂S₃, which is much similar to iron(II,III) oxide. It occurs naturally as the sulfide mineral greigite and is magnetic. It is a bio-mineral produced by and found in magnetotactic bacteria. It is a mixed valence compound, featuring both Fe^2+ and Fe^3+ centers, in 1:2 ratio.

Crystal structure

The crystallographic unit cell is cubic, with space group Fd3m. The S anions form a cubic close-packed lattice, and the Fe cations occupy both tetrahedral and octahedral sites.[1][2]

Crystal structure of iron(II,III) sulfide projected along the [110] direction

• 
  Emphasis on the SFe₄ tetrahedra.
• 
  Emphasis on the FeS₄ tetrahedra
• 
  Emphasis on the FeS₆ octahedra

Magnetic and electronic properties

Like the related oxide magnetite (Fe₃O₄), iron(II,III) sulfide is ferrimagnetic, with the spin magnetic moments of the Fe^III centers in the tetrahedral sites oriented in the opposite direction as those in the octahedral sites, and a net magnetization. Both metal sites have high spin quantum numbers. The electronic structure of greigite is that of a half metal.[3][4]

References

1. Anthony, John W.; Bideaux, Richard A.; Bladh, Kenneth W.; Nichols, Monte C., eds. (1990). "Greigite" (PDF). Handbook of Mineralogy. Vol. I (Elements, Sulfides, Sulfosalts). Chantilly, VA, US: Mineralogical Society of America. ISBN 978-0962209703. Retrieved December 5, 2011.
2. Vaughan, D. J.; Craig, J. R. “Mineral Chemistry of Metal Sulfides" Cambridge University Press, Cambridge: 1978. ISBN 0-521-21489-0.
3. Devey, Anthony; Grau-Crespo, R.; De Leeuw, N.H. (2009). "Electronic and magnetic structure of Fe₃S₄: GGA+U investigation". Physical Review B. 79 (19): 195126. Bibcode:2009PhRvB..79s5126D. doi:10.1103/PhysRevB.79.195126.
4. Wang, Jun; Cao, Shi-He; Wu, Wei; Zhao, Guo-Meng (2011). "The Curie temperature and magnetic exchange energy in half-metallic greigite Fe₃S₄". Physica Scripta. 83 (4): 045702. Bibcode:2011PhyS...83d5702W. doi:10.1088/0031-8949/83/04/045702.

Further reading

• Mann, Stephen; Sparks, Nicholas H. C.; Frankel, Richard B.; Bazylinski, Dennis A.; Jannasch, Holger W. (1990). "Biomineralization of ferrimagnetic greigite (Fe₃S₄) and iron pyrite (FeS₂) in a magnetotactic bacterium". Nature. 343 (6255): 258. Bibcode:1990Natur.343..258M. doi:10.1038/343258a0. S2CID 4351424.
• Roberts, A (1995). "Magnetic properties of sedimentary greigite (Fe₃S₄)". Earth and Planetary Science Letters. 134 (3–4): 227–236. Bibcode:1995E&PSL.134..227R. doi:10.1016/0012-821X(95)00131-U.
• Heywood, B. R.; Bazylinski, D. A.; Garratt-Reed, A.; Mann, S.; Frankel, R. B. (1990). "Controlled biosynthesis of greigite (Fe₃S₄) in magnetotactic bacteria". Naturwissenschaften. 77 (11): 536–538. Bibcode:1990NW.....77..536H. doi:10.1007/BF01139266. S2CID 28912546.
• Reynolds, R. L.; Tuttle, M. L.; Rice, C. A.; Fishman, N. S.; Karachewski, J. A.; Sherman, D. M. (1994). "Magnetization and geochemistry of greigite-bearing Cretaceous strata, North Slope basin, Alaska". American Journal of Science. 294 (4): 485–528. doi:10.2475/ajs.294.4.485.
• Snowball, Ian; Thompson, Roy (1988). "The occurrence of Greigite in sediments from Loch Lomond". Journal of Quaternary Science. 3 (2): 121–125. Bibcode:1988JQS.....3..121S. doi:10.1002/jqs.3390030203.
• Stanjek, H.; Fassbinder, J. W. E.; Vali, H.; Wagele, H.; Graf, W. (1994). "Evidence of biogenic greigite (ferrimagnetic Fe₃S₄) in soil". European Journal of Soil Science. 45 (2): 97–103. doi:10.1111/j.1365-2389.1994.tb00490.x.
• Hoffmann, V (1992). "Greigite (Fe₃S₄): magnetic properties and first domain observations". Physics of the Earth and Planetary Interiors. 70 (3–4): 288–301. Bibcode:1992PEPI...70..288H. doi:10.1016/0031-9201(92)90195-2.
• Fassbinder, Jörg W. E.; Stanjek, Helge (1994). "Magnetic properties of biogenic soil greigite (Fe₃S₄)". Geophysical Research Letters. 21 (22): 2349–2352. Bibcode:1994GeoRL..21.2349F. doi:10.1029/94GL02506.