Propriedades estruturais e microestruturais de manganitas dopadas com cobre

We report a structural study on polycrystalline La0.86Sr0.14Mn1-y Cu yO3+delta samples (y = 0, 0.05, 0.10, 0.15, 0.20) using refinement of powder X-ray diffraction data and analysis of scanning electron microscopy images. It is found that the structure remains rhombohedral through the whole series, with a decrease in the average Mn-Mn bond distances, slight variations in Mn-O-Mn angle and reduction in the unit cell volume with increasing Cu amounts. The values of Mn-Mn distances suggest compact structures with d within ±1%. Scanning electron microscopy images reveal homogeneous microstructure in all samples, besides a trend for smaller grains and larger porosity with increasing Cu content.

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Bibliographic Details
Main Authors: Victor,Rodolfo Araujo, Orlando,Marcos Tadeu D'Azeredo, Freitas,Jair C. C.
Format: Digital revista
Language:Portuguese
Published: Sociedade Brasileira de Química 2007
Online Access:http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422007000700004
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