Transição metal-isolante em fulleritos dopados com metais alcalinos

Authors

  • José Carlos Cechin Departamento de Física, Centro de Ciências Naturais e Exatas - CCNE Universidade Federal de Santa Maria - UFSM, Santa Maria, RS,
  • Ronaldo Mota Departamento de Física, Centro de Ciências Naturais e Exatas - CCNE Universidade Federal de Santa Maria - UFSM, Santa Maria, RS,

DOI:

https://doi.org/10.5902/2179460X26537

Abstract

In the present article of the metallic or insulating characters of alkali doped is studied. In particular, the ocurrence of a metalic phase in potassium doped systems and its nonocurrence in sodium doped systems are analysed through the Gutzwiller approximation on a deqenerate Hubbard model. Using interaction and bandwidth parameters derived from INDO-CI calculations in the molecular cluster approach, as presented earlier by Coutinho, Canuto, Mota and Fazzio, the nonmetal-metal transitions are discussed in the systems. From the obtained results for the relation between the derived parameters and doping concentrations, it is possible to help to elucidate the diverse behaviours presented by fullerides doped with potassium and sodium.

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References

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Published

1996-12-09

How to Cite

Cechin, J. C., & Mota, R. (1996). Transição metal-isolante em fulleritos dopados com metais alcalinos. Ciência E Natura, 18(18), 07–26. https://doi.org/10.5902/2179460X26537

Issue

CIÊNCIA E NATURA, V. 18, N. 18, 1996

Section

Articles

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