Raman spectra of isolated and interconnected pyramidal XS3 groups (X = Sb,Bi) in stibnite, bismuthinite, kermesite, stephanite and bournonite
- Author(s)
- Anton Beran, Eugen Libowitzky, Sherif Kharbish
- Abstract
Oriented single-crystals of stibnite, bismuthinite, kermesite, stephanite and bournonite were investigated by polarizedRaman spectroscopy. The obtained spectra were compared to those of the sulfosalt minerals tetrahedrite and pyrargyrite. Whereas thelatter show isolated SbS3 groups with ideal trigonal symmetry, the former show distorted XS3 (X ¿ Sb,Bi) groups with lowersymmetry. Moreover, in stibnite and isostructural bismuthinite the pyramidal groups are interconnected to infinite ribbons, and evento sheets in kermesite. The internal vibrations, i.e. the stretching and bending modes, of the SbS3 groups occur at _340-180 cm_1,those of the BiS3 groups in bismuthinite at _280-150 cm_1. The higher mass and the longer bond distances of the BiS3 groups readilyexplain the lower wavenumbers of the latter. However, even for the SbS3 groups a negative correlation between bond distances andvibrational wavenumbers is observed. Moreover, in those minerals with a wide range of pyramidal bond distances, i.e. stibnite,kermesite, bismuthinite, a more extended range of vibrational modes is observed. A clear distinction between Raman spectra ofseparated and interconnected SbS3 groups is not observed.
- Organisation(s)
- Department of Mineralogy and Crystallography
- External organisation(s)
- Zagazig University
- Journal
- European Journal of Mineralogy: an international journal of mineralogy, geochemistry and related sciences
- Volume
- 21
- Pages
- 325-333
- No. of pages
- 9
- ISSN
- 0935-1221
- Publication date
- 2009
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 105113 Crystallography, 1030 Physics, Astronomy, 105116 Mineralogy
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/e82017eb-7889-4820-9f8c-098c67ad5da0