Navegação Ciências Exatas e da Terra por Assunto "Compostos de valencia mista"

Resultados 1-3 de 3

    • Generic model of the colossal magnetoresistance pyrochlore Tl/sub 2/Mn/sub 2/O/sub 7/ 

      Ventura, Cecilia Ileana; Gusmao, Miguel Angelo Cavalheiro (2002) [Artigo de periódico]
      The colossal magnetoresistance (CMR) exhibited by the pyrochlore compound Tl₂Mn₂O₇ was discovered in 1996. Important differences with CMR Mn-perovskite compounds regarding crystal structure and electronic properties were ...

    • Green-Function Method for a Mixed-Valence Hamiltonian 

      Simões, Acirete Souza da Rosa; Iglesias, Jose Roberto; Anda, Enrique V. (1984) [Artigo de periódico]
      A Green-function diagrammatic method is utilized to calculate the occupation number of a narrow (j) band in a mixed-valence system. The method is a generalization of the Hubbard-1 approximation for a two-band Hamiltonian. ...

    • Hall effect in Ce 1-x Y x/Pd 3 mixed-valence alloys 

      Fert, Albert R.; Pureur Neto, Paulo; Hamzic, Amir; Kappler, J.P. (1985) [Artigo de periódico]
      Mixed-valence and Kondo lattice systems exhibit large anomalous Hall coefficients with a striking change of sign at low temperature in severa! systems (CePd3, CeCu6, ... , etc.). We have studied the Hall effect of Ce1-x ...