Publication: FT-Raman study of three syntetic solid solutions formed by orthorhombic sulfates: Celestite-barytes, barytes-anglesite and celestite-anglesite
Loading...
Official URL
Full text at PDC
Publication Date
2000
Advisors (or tutors)
Editors
Journal Title
Journal ISSN
Volume Title
Publisher
Taylor & Francis
Citations
Exportar
Abstract
In, the present work, three different solid solutions whose end-members are
the orthorhombic sulfates celestite (SrS04), barytes (BaS04) and anglesite (PbS04) are studied using FT-Raman spectroscopy. Sulfate anion symmetric
internal modes have been examined in detail by means of band-shape analysis and
component fitting procedures. The symmetric stretching mode v,(A,)changes its
wavenumber position lillearly with the cationic composition of the samples which
further confirrns the ideal character of the solid solutions studied. The corresponding full-width at half-height is strongly increased in the central
components of the different solid solutions which can be understood as an effect
of the positional disorder induced by random cationic substitution. Similar results
are observed in the syrnmetric bending mode, ~(E). The study of the low
frequency spectral region permits one to differentiate traslational modes of the
sulfate anion, which changes its wavenumberposition when the alkali-earth metal ion changes from rotational modes. This permits the tentative band assignement of
the anglesite rotational Raman bands at 134 and 152 cm-1, which were previously
not assigned.