Structural properties of Fe3+ substituted yttrium iron garnet

The compositional dependence of structural parameters like cation distribution, lattice constant, x-ray density, bulk density, porosity, shrinkages and particle size have been studied for Y3-xFe5+xO12 (x 0.00, 0.05, 0.15 and 0.30) garnet system. It is found that substituted Fe3+ ions occupy dodecahedral sites while Fe2+ ion concentration, determined through EDAX, occupy octahedral (a-) sites in the crystal structure. The values of lattice constant obtained from experimentally estimated cation distribution are not in agreement with measured values; suggest that practically Fe3+ ion substitution does not affect the lattice constant. All the parameters studied are inter linked having effect on transport properties. (author)