Raman spectra (200-1300 cm-1) were measured for synthesized jarosite-group compounds [MFe3(SO4)2(OH)6, M+ = K+, NH4+, Na+, Ag+, and 1/2Pb2+). The Raman spectra of jarosite-group compounds are characterized by a tendency for the wavenumbers assigned to two vibrational modes of SO42-, ν1(SO42-) and ν3(SO42-), and three vibrational modes of Fe-O bonds, to decrease with increase in the c unit-cell parameter. The wavenumbers assigned to the ν2(SO42-) and ν4(SO42-) vibrational modes are independent of the value of c. For plumbojarosite, the peaks corresponding to the ν1(SO42-) and ν3(SO42-) vibrational modes are broad owing to two overlapping peaks assigned to two types of sulfate groups, SO42- ions adjacent and not adjacent to Pb2+ ions. Raman spectra can serve to identify the specific type of jarosite-group compound in poorly crystalline or low-concentration geochemical samples.
|Number of pages||11|
|Publication status||Published - Oct 1998|
All Science Journal Classification (ASJC) codes
- Geochemistry and Petrology