Publication details

A Raman spectroscopic study of bukovskýite Fe2(AsO4)(SO4)(OH) . 7H2O, a mineral phase with significant role in arsenic migration

Authors

LOUN Jan ČEJKA Jiří SEJKORA Jiří PLÁŠIL Jakub NOVÁK Milan FROST Ray Leslie PALMER Sara KEEFFE Eloise C.

Year of publication 2011
Type Article in Periodical
Magazine / Source Journal of Raman Spectroscopy
MU Faculty or unit

Faculty of Science

Citation
Doi http://dx.doi.org/10.1002/jrs.2900
Field Geology and mineralogy
Keywords bukovskyite; Raman spectroscopy; arsenate; sulfate; hydroxyl ions; molecular water
Description The Raman spectrum of bukovskyite [Fe2(3+)(OH)(SO4)(AsO4) . 7H2O] has been studied and compared with that of an amorphous gel containing specifically Fe, As and S, which is understood to be an intermediate product in the formation of bukovskyite. The observed bands are assigned to the stretching and bending vibrations of (SO4)2- and (AsO4)3- units, stretching and bending vibrations and vibrational modes of hydrogen-bonded water molecules, stretching and bending vibrations of hydrogen-bonded (OH)- ions and Fe3+ -(O,OH) units. The approximate range of O-H ... O hydrogen bond lengths was inferred from the Raman spectra. Raman spectra of crystalline bukovskyite and of the amorphous gel differ in that the bukovskyite spectrum is more complex, the observed bands are sharp and the degenerate bands of (SO4)2- and (AsO4)3- are split and more intense. Lower wavenumbers of delta H2O bending vibrations in the spectrum of the amorphous gel may indicate the presence of weaker hydrogen bonds compared to those in bukovskyite.
Related projects:

You are running an old browser version. We recommend updating your browser to its latest version.

More info