A crystal structure study of La1-xCaxMnO3 nanoparticles

作者：Duan YW^*; Li JG

来源：Modern Physics Letters B, 2004, 18(12-13): 597-602.

DOI：10.1142/S0217984904007153

• complex manganites
• nanoparticles
• crystal structure

Using a sol-gel method, La1-xCaxMnO3 (0 less than or equal to x less than or equal to 0.5) nanoparticles with nearly the same average grain size of about 21 nm and different Ca contents, La0.8Ca0.2MnO3 nanoparticles with various average grain sizes were prepared. Crystal structure was investigated by X-ray diffraction. Increasing Ca content and decreasing grain size can lead to the average Mn-O bond lengths decrease and Mn-O-Mn bond angles increase. The crystal symmetry changes from orthorhombic to cubic as x greater than or equal to 0.3 for the La1-xCaxMnO3 (0 less than or equal to x less than or equal to 0.5) nanoparticles with nearly the same average grain size and D similar to 16 nm for the La0.8Ca0.2MnO3 nanoparticles with various grain sizes. Small-size effect and surface effect may be the reasons of the lattice distortion and structure transition.

• 出版日期2004-5-30
• 单位兰州大学