MOSSBAUER SPECTROSCOPIC INVESTIGATION OF SOME IRON-CONTAINING SODIUM-PHOSPHATE GLASSES

Fe-57 Mossbauer spectroscopy has been used to investigate the effect o f an addition of an increasing amount of Fe2O3 on the iron environment in a number of sodium phosphate glasses of composition (1-x)NaPO3 . x Fe(2)O(3) (x = 0.05, 0.1, 0.15), prepared in air under the same condit ions. High-spin ferric and ferrous iron in octahedral coordination is present in all the samples. Two sites, with different disorder and oct ahedral distortion, are occupied by ferric ions. An increasing iron co ntent results in an increase in the distortion and disorder of the fer ric sites and, in addition, in a redistribution of the iron atoms betw een the two ferric sites.