The effect of gallium substitution for iron on the magnetic properties of hydronium iron jarosite

Gallium has been partially substituted for iron in the hydronium iron jaros ite H3O . Fe-3(SO4)(2)(OH)(6), a material with a Kagome lattice of iron-oxy gen octahedra, allowing the controlled introduction of non-magnetic defects in the magnetic lattice. The highly frustrated nature of the magnetic inte ractions is partially relaxed by the substitution, which unlocks spins and thus increases the magnetic susceptibility. The non-linear susceptibility i s reported. Comparison of intentionally doped and "pure" jarosite prepared under different synthetic conditions indicates that the defect concentratio n and the magnetic properties are variable dependent on the synthetic metho d. (C) 1999 Published by Elsevier Science B.V. All rights reserved.