Structural study of Na2O–FeO–Fe2O3–P2O5 glasses by Raman and Mössbauer spectroscopy

Abstract Five series of Na 2 O–FeO–Fe 2 O 3 –P 2 O 5 glasses with compositional ranges of 3.0  Fe ) of the Fe ions decreased, as indicated by the Mossbauer data. The interaction between phosphate anions and iron polyhedra causes systematic changes in the Raman frequencies as well as peak intensities.