Radial-distribution-function analysis was used to study the structure of x-
ray amorphous Fe-Zr-O materials prepared by heat treatment between 383 and
673 K. The chemical and structural formulas of the materials were establish
ed. The results demonstrate that the introduction of Fe3+ into ZrO2 favors
the formation of vacancies and reduces interatomic distances in comparison
with cubic ZrO2. The materials contain OH- groups, whose concentration decr
eases with increasing heat-treatment temperature.