We present a study of the intermediate and final phases during mechanosynth
esis of ZnFe2O4. Mossbauer measurements at T = 4.2 K indicate creation of o
xygen vacancies and local disorder at Fe sites during milling. Magnetizatio
n data show lack of saturation and irreversibility at high fields. Our data
is qualitatively well described by a model of particles with a magnetic or
dered core coupled to a spin-disordered surface layer. (C) 1999 Published b
y Elsevier Science B.V. All rights reserved.