Structural, magnetic, and transport properties in La0.7Ca0.3Mn1-xScxO3

Structural, magnetic, and transport properties of polycrystalline La0.7Ca0. 3Mn1-xScxO3 have been experimentally investigated. Single-phase samples are obtained in the range 0 less than or equal tox less than or equal to0.25 b y the soft chemical synthesis route. The substitution of Sc3+ at the Mn sit e results in reductions in the Curie temperature T-c and in the magnetic mo ment per Mn ion. The T-c transition temperature becomes broader with x, and the magnetic spontaneous state has changed into a cluster glass state for the sample of x=0.1. In addition, great enhancement in resistance and magne toresistance effect is observed in the Sc-doped samples. In our case the no table doping effects can be mainly ascribed to the variation in the Mn3+-O2 --Mn4+ network and to the magnetic disorder caused by the presence of the l arge and nonmagnetic Sc3+ ions in the Mn sublattice. (C) 2001 American Inst itute of Physics.