ThermoRaman spectroscopic study of kintoreite.

Abstract

ThermoRaman spectroscopy has been used to study the molecular structure and thermal decomposition of kintoreite, a phosphated jarosite PbFe3(PO4)2(OH,H2O)6. Infrared spectroscopy shows the presence of significant amounts of water in the structure as well as hydroxyl units. In contrast, no water was observed for segnitite (the arsenojarosite) as determined by infrared spectroscopy. The Raman spectra at 77 K exhibit bands at 974.6, 1003.2 and 866.5 cm(-1). These bands are attributed to the symmetric stretching vibrations of (PO4)3-, (SO4)3- and (AsO4)3- units. Raman spectroscopy confirms the presence of both arsenate and phosphate in the structure. Bands at 583.7 and 558.1 cm(-1) in the 77 K spectrum are assigned to the nu4 (PO4)3- bending modes. ThermoRaman spectroscopy of kintoreite identifies the temperature range of dehydration and dehydroxylation.

• Authors: Ray L Frost, Matt L Weier, Wayde Martens, Stuart Mills
• Journal: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy (Spectrochim Acta A Mol Biomol Spectrosc) Vol. 63 Issue 2 Pg. 282-8 (Feb 2006) ISSN: 1386-1425 [Print] England
• PMID: 15970459 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Ferric Compounds
• Phosphates
• Sulfates
• jarosite
• kintoreite

Topics

• Ferric Compounds (chemistry)
• Molecular Structure
• Phosphates (chemistry)
• Spectrophotometry, Infrared
• Spectrum Analysis, Raman (methods)
• Sulfates (chemistry)
• Temperature