摘要
Ⅰ. INTRODUCTION The M?ssbauer spectra （MS） of a Ca2+, In2+ and Ge4+ substituted yttrium iron garnet （YIG）-Y2.78Ca0.25In0.60Ge0.25Fe4.11O12（Y—Ca—In—GeIG） cannot be resolved simply into two sets of octahedral（a） and tetrahedral （d） subspectra, since the nonequivalent environment （NE） resulting from random distribution of nonmagnetic ions can influence the MS. If the probabilities Pnm of NE which is less than 8％, were neglected, then the （a） and （d） subspectra each can be again resolved into two and three sets
