MOSSBAUER EFFECT FOR 57FE IN SNO2

The nuclear hyperfine structure corresponding to the crystal field split states of trivalent iron in SnO2 have been observed by 57Fe Mössbauer effect. These hyperfine effects disappear with the increase in iron concentration. The effects of heat treatments on SnO2. 57Fe system, namely, the production of metallic iron in hydrogen treated absorbers, and production of Fe2+ state in addition to the normal Fe3+ state on vacuum firing, are also discussed. In the low concentration region, these changes, caused by thermal treatment, are associated with the change in the relaxation time so that the hyperfine structure almost disappears. © 1969.