Journal of

GEOsciences

  (Formerly Journal of the Czech Geological Society)

Original Paper

Sherif Kharbish

Raman spectra of minerals containing interconnected As(Sb)O₃ pyramids: trippkeite and schafarzikite

Journal of Geosciences, volume 57 (2012), issue 1, 53 - 62

DOI: http://doi.org/10.3190/jgeosci.111

Oriented single-crystals of trippkeite (CuAs₂O₄) and an isostructural mineral schafarzikite (FeSb₂O₄) were investigated by polarized Raman spectroscopy. The internal vibrations, i.e. the stretching and bending modes, of trippkeite occur between 250 and 850 cm^-1, and those of schafarzikite between 200 and 750 cm^-1. The higher mass and the longer bond distances of the SbO₃ groups readily explain the lower wavenumbers of the latter. Comparing the spectra of minerals containing XO₃ pyramids with those of the minerals from the present study, approximate similarities in the spectral features are evident. A clear distinction between Raman spectra of separated and interconnected (As,Sb)O₃ groups is not observed.