Óxidos de ferro magnéticos de um tufito da região do Alto Paranaíba, MG


Autoria(s): Silva,Fernando Dias da; Couceiro,Paulo Rogério da Costa; Fabris,José Domingos; Goulart,Antonio Taranto; Ker,João Carlos
Data(s)

01/02/2005

Resumo

The Mössbauer analysis along with the structural Rietveld refinement based on powder X-ray data for the magnetic fraction (saturation magnetization, sigma = 19 J T-1 kg-1) separated from a tuffite material from Alto Paranaíba, state of Minas Gerais, Brazil, reveal that a (Ti, Mg)-rich maghemite (deduced sigma = 17 J T-1 kg-1) and, for the first time observed in this lithodomain, magnesioferrite (characteristic sigma = 21 J T-1 kg-1) respond for the magnetization of the rock material. Consistent models for the ionic distribution in these iron-rich spinel structures are proposed.

Formato

text/html

Identificador

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422005000100002

Idioma(s)

pt

Publicador

Sociedade Brasileira de Química

Fonte

Química Nova v.28 n.1 2005

Palavras-Chave #magnesioferrite #Rietveld #Mössbauer
Tipo

journal article