Perovskite manganates of the type La~1~-~xCa~xMnO~3 is of considerable interest in solid state physics and chemistry because of its special magneto-transport properties, colossal magnetoresistance (CMR) effect. We reported here a new route to the nanosized La~1~- ~xCa~xMnO~3 perovskite crystalline complex oxides at relatively low calcination temperature (450℃-600℃) using amorphous molecular alloys of La-Ga-Mn-DTPA as precursors. The size and topography of the oxides are dependent on the annealing temperature of the precursors. The particle size is, ranging from 25nm to 100nm determined by TEM under calcinating temperature of 450℃ to 600℃. The AC susceptibility is found to be strongly dependent on the particle size. Preliminary magnetoresistance research on pellet sample shows spin- polarized tunneling behavior at low temperature range.

Key words: AMORPHOUS MATERIALS, NANOPHASE MATERIALS, LANTHANUM OXIDE, CALCIUM OXIDE, MANGANESE OXIDE, DOUBLE OXIDE, PEROVSKITE TYPE STRUCTURE, TRANSMISSION ELECTRON MICROSCOPY, MAGNETIZATION